Thermodynamic study and intrinsic type II superconductivity in the A-15 compound V3Si

International Nuclear Information System (INIS)

Muto, Y.; Toyota, N.; Noto, K.; Akutsu, K.; Isino, M.; Fukase, T.

1979-01-01

The specific heat of a single crystal of the A-15-type compound V 3 Si in the normal, mixed, and superconducting states has been measured from 4 to 30 K in magnetic fieldsup to 50 kOe. The analysis has been performed in a self-consistent way based on the second-order phase transition from the normal to the superconducting state. The thermodynamic critical field and then various physical parameters characterizing the superconducting and normal states are almost consistently derived from the thermodynamcis and the microscopic BCS-GLAG theory. It is confirmed that V 3 Si is an intrinsic type II superconductor with a high intrinsic GL parameter k 0

Compound-specific δ15N amino acid measurements in littoral mussels in the California upwelling ecosystem: a new approach to generating baseline δ15N Isoscapes for coastal ecosystems.

Directory of Open Access Journals (Sweden)

Natasha L Vokhshoori

Full Text Available We explored δ(15N compound-specific amino acid isotope data (CSI-AA in filter-feeding intertidal mussels (Mytilus californianus as a new approach to construct integrated isoscapes of coastal primary production. We examined spatial δ(15N gradients in the California Upwelling Ecosystem (CUE, determining bulk δ(15N values of mussel tissue from 28 sites between Port Orford, Oregon and La Jolla, California, and applying CSI-AA at selected sites to decouple trophic effects from isotopic values at the base of the food web. Bulk δ(15N values showed a strong linear trend with latitude, increasing from North to South (from ∼ 7‰ to ∼ 12‰, R(2 = 0.759. In contrast, CSI-AA trophic position estimates showed no correlation with latitude. The δ(15N trend is therefore most consistent with a baseline δ(15N gradient, likely due to the mixing of two source waters: low δ(15N nitrate from the southward flowing surface California Current, and the northward transport of the California Undercurrent (CUC, with (15N-enriched nitrate. This interpretation is strongly supported by a similar linear gradient in δ(15N values of phenylalanine (δ(15NPhe, the best AA proxy for baseline δ(15N values. We hypothesize δ(15N(Phe values in intertidal mussels can approximate annual integrated δ(15N values of coastal phytoplankton primary production. We therefore used δ(15N(Phe values to generate the first compound-specific nitrogen isoscape for the coastal Northeast Pacific, which indicates a remarkably linear gradient in coastal primary production δ(15N values. We propose that δ(15N(Phe isoscapes derived from filter feeders can directly characterize baseline δ(15N values across major biochemical provinces, with potential applications for understanding migratory and feeding patterns of top predators, monitoring effects of climate change, and study of paleo- archives.

Superconductivity and specific heat of titanium base A15 alloys

International Nuclear Information System (INIS)

Junod, A.; Flukiger, R.; Muller, J.

1976-01-01

Experimental data on the superconducting transition temperature, and low temperature specific heat, together with X-ray investigations, are reported for binary and pseudo-binary compounds of Ti with the A15-type structure. A 'true' relative maximum of the coefficient of the electronic specific heat, γ, as well as the superconducting transition temperature, Tsub(c), occurs in the Tisub(3)Irsub(1-x)Ptsub(x) system near x = 0.2. Tisub(3)Irsub(0.8)Ptsub(0.2) shows the lowest Debye temperature, theta 0 , of all A15-type compounds known to date. The anomalous temperature dependence of the lattice specific heat may be reproduced by a model phonon spectrum similar to that of Nb 3 Sn. (author)

A fluorescence-based rapid screening assay for cytotoxic compounds

International Nuclear Information System (INIS)

Montoya, Jessica; Varela-Ramirez, Armando; Estrada, Abril; Martinez, Luis E.; Garza, Kristine; Aguilera, Renato J.

2004-01-01

A simple fluorescence-based assay was developed for the rapid screening of potential cytotoxic compounds generated by combinatorial chemistry. The assay is based on detection of nuclear green fluorescent protein (GFP) staining of a human cervical cancer cell line (HeLa) carrying an integrated histone H2B-GFP fusion gene. Addition of a cytotoxic compound to the HeLa-GFP cells results in the eventual degradation of DNA and loss of the GFP nuclear fluorescence. Using this assay, we screened 11 distinct quinone derivatives and found that several of these compounds were cytotoxic. These compounds are structurally related to plumbagin an apoptosis-inducing naphthoquinone isolated from Black Walnut. In order to determine the mechanism by which cell death was induced, we performed additional experiments with the most cytotoxic quinones. These compounds were found to induce morphological changes (blebbing and nuclear condensation) consistent with induction of apoptosis. Additional tests revealed that the cytotoxic compounds induce both necrotic and apoptotic modes of death

Assessment of off-stoichiometric Zr33-xFe52+xSi15 C14 Laves phase compounds as permanent magnet materials

Science.gov (United States)

Gabay, A. M.; Hadjipanayis, G. C.

2018-05-01

Recently, Fe-based rare-earth-free compounds with non-cubic crystal structures were proposed as a base for permanent magnets which would not rely on critical elements. In this work, two series of alloys, Zr27Fe73-wSiw (0 ≤ w ≤ 15) and Zr33-xFe52+xSi15 (0 ≤ x ≤ 11), were prepared and characterized after annealing at 1538 K in order to determine the fundamental magnetic properties of the C36 and C14 hexagonal Laves phase compounds. A mixture of the cubic C15 and Zr6Fe23 structures was observed instead of the expected C36 structure. The hexagonal C14 was found in all Zr33-xFe52+xSi15 alloys with its lattice parameters linearly decreasing as the Fe(Si) atoms occupy the Zr sites in the Laves phase crystal structure. The solubility limit of Fe in the C14 structure at 1538 K corresponds to x = 9.5. The Curie temperature of the C14 compounds increases with deviation from the Laves phase stoichiometry from 290 K to 530 K. The room-temperature spontaneous magnetization also increases reaching, after correcting for the non-magnetic impurities, a value of 6.7 kG. The magnetocrystalline anisotropy of the off-stoichiometric C14 Laves phase was found to be uniaxial with the easy magnetization direction parallel to the hexagonal axis. Unfortunately, the anisotropy field, which does not exceed 10 kOe, is not sufficiently high to make the compounds interesting as permanent magnet materials.

Ba9V3Se15: a novel compound with spin chains

Science.gov (United States)

Zhang, Jun; Liu, Min; Wang, Xiancheng; Zhao, Kan; Duan, Lei; Li, Wenmin; Zhao, Jianfa; Cao, Lipeng; Dai, Guangyang; Deng, Zheng; Feng, Shaomin; Zhang, Sijia; Liu, Qingqing; Yang, Yi-feng; Jin, Changqing

2018-05-01

In this work, a novel compound Ba9V3Se15 with one-dimensional (1D) spin chains was synthesized under high-pressure and high-temperature conditions. It was systematically characterized via structural, magnetic, thermodynamic and transport measurements. Ba9V3Se15 crystallizes into a hexagonal structure with a space group of P-6c2 (188) and the lattice constants of a  =  b  =  9.5745(7) Å and c  =  18.7814(4) Å. The crystal structure consists of face-sharing octahedral VSe6 chains along c axis, which are trimeric and arranged in a triangular lattice in ab-plane. Ba9V3Se15 is a semiconductor and undergoes complex magnetic transitions. In the zero-field-cooled (ZFC) process with magnetic field of 10 Oe, Ba9V3Se15 sequentially undergoes ferrimagnetic and spin cluster glass transition at 2.5 K and 3.3 K, respectively. When the magnetic field exceeds 50 Oe, only the ferrimagnetic transition can be observed. Above the transition temperature, the specific heat contains a significant magnetic contribution that is proportional to T 1/2. The calculation suggests that the nearest neighbor (NN) intra-chain antiferromagnetic exchange J 1 is much larger than the next nearest neighbor (NNN) intra-chain ferromagnetic exchange J 2. Therefore, Ba9V3Se15 can be regarded as an effective ferromagnetic chains with effective spin-1/2 by the formation of the V(2)(↓) V(1)(↑) V(2)(↓) cluster.

Density of states model for the lattice transformation in A-15 compounds

International Nuclear Information System (INIS)

Pietrass, B.; Handstein, A.; Behr, G.

1980-01-01

The cubic-tetragonal lattice transformation in A-15 compounds is described by an empirical model in which the density of states function near the Fermi energy is characterized by a two-parametric peak in addition to the constant part. Two types of peak splitting under tetragonal deformation are considered, leading to qualitatively different results about the phase transition. Results are given for the order parameter, the phase stability, the soft elastic modulus, and the paramagnetic spin susceptibility. Comparing with measurements of the magnetic susceptibility of V 3 Si single crystals near the phase transition a better agreement is obtained for a twofold degenerate density of states peak than for a threefold degenerate one. (author)

Quinoline-Based Hybrid Compounds with Antimalarial Activity

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Xhamla Nqoro

2017-12-01

Full Text Available The application of quinoline-based compounds for the treatment of malaria infections is hampered by drug resistance. Drug resistance has led to the combination of quinolines with other classes of antimalarials resulting in enhanced therapeutic outcomes. However, the combination of antimalarials is limited by drug-drug interactions. In order to overcome the aforementioned factors, several researchers have reported hybrid compounds prepared by reacting quinoline-based compounds with other compounds via selected functionalities. This review will focus on the currently reported quinoline-based hybrid compounds and their preclinical studies.

Anti-plasmodial activity of Dicoma tomentosa (Asteraceae) and identification of urospermal A-15-O-acetate as the main active compound

Science.gov (United States)

2012-01-01

Background Natural products could play an important role in the challenge to discover new anti-malarial drugs. In a previous study, Dicoma tomentosa (Asteraceae) was selected for its promising anti-plasmodial activity after a preliminary screening of several plants traditionally used in Burkina Faso to treat malaria. The aim of the present study was to further investigate the anti-plasmodial properties of this plant and to isolate the active anti-plasmodial compounds. Methods Eight crude extracts obtained from D. tomentosa whole plant were tested in vitro against two Plasmodium falciparum strains (3D7 and W2) using the p-LDH assay (colorimetric method). The Peters’ four-days suppressive test model (Plasmodium berghei-infected mice) was used to evaluate the in vivo anti-plasmodial activity. An in vitro bioguided fractionation was undertaken on a dichloromethane extract, using preparative HPLC and TLC techniques. The identity of the pure compound was assessed using UV, MS and NMR spectroscopic analysis. In vitro cytotoxicity against WI38 human fibroblasts (WST-1 assay) and haemolytic activity were also evaluated for extracts and pure compounds in order to check selectivity. Results The best in vitro anti-plasmodial results were obtained with the dichloromethane, diethylether, ethylacetate and methanol extracts, which exhibited a high activity (IC50 ≤ 5 μg/ml). Hot water and hydroethanolic extracts also showed a good activity (IC50 ≤ 15 μg/ml), which confirmed the traditional use and the promising anti-malarial potential of the plant. The activity was also confirmed in vivo for all tested extracts. However, most of the active extracts also exhibited cytotoxic activity, but no extract was found to display any haemolytic activity. The bioguided fractionation process allowed to isolate and identify a sesquiterpene lactone (urospermal A-15-O-acetate) as the major anti-plasmodial compound of the plant (IC50 < 1 μg/ml against both 3D7 and W2 strains). This was also

A spin echo study of A15 intermetallic compounds

International Nuclear Information System (INIS)

Schoep, G.K.

1976-01-01

This thesis mainly concerns the measurement of spin-lattice relaxation times in intermetallic compounds of the bcc lattice structure, having the formula V 3 X (C = Pt, Ir, Os, Pd, Rh, Ni, Co, Au). When, in a spin echo experiment, a two-pulse sequence was applied, several quadrupolar echoes were observed. Special attention is given to the 'forbidden' echoes (absol.(Δm')GT1) in V 3 Au and V 3 Co. In relation to the V 3 X compounds, several characteristics are discussed including temperature dependence and concentration dependence of spin relaxation times, superconductivity and the importance of d-state electrons in determination of the spin relaxation times. Finally, the above characteristics were determined for 6 different samples of the vanadium-gold alloy, V 3 Au, specifically

Production of 15N-enriched nitric acid (H15NO3

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C. R. Sant Ana Filho

2008-12-01

Full Text Available Techniques that employ 15N have proved to be an important tool in many areas of the agronomic and biomedical sciences. Nevertheless, their use is limited by methodological difficulties and by the price of compounds in the international market. Nitric compounds (15NO3- have attracted the interest of researchers. However, these compounds are not currently produced in Brazil. Thus, in the present work H15NO3 was obtained from the oxidation of anhydrous 15NH3. The method we used differs from the industrial process in that the absorption tower is replaced with a polytetrafluoroethylene-lined, stainless-steel hydration reactor. The process output was evaluated based on the following parameters: reaction temperature; ratio of reagents; pressure and flow of 15NH3(g through the catalyst (Pt/Rh. The results showed that, at the best conditions (500 ºC; 50 % excess O2; 0.4 MPa; and 3.39 g.min-1 of 15NH3, a conversion percentage (N-15NH3 to N-15NO3- of 62.2 %, an overall nitrogen balance (N-15NH3 + N-15NO3- of 86.8 %, and purity higher than 99 % could be obtained.

Dispersion of complex dielectric constant and electronic characteristics of the compounds Nb-Al and Nb-Ge with A15 structure

International Nuclear Information System (INIS)

Kuzmichev, N.D.; Levchenko, I.S.; Motulevich, G.P.

1989-01-01

This paper reports that the dispersions of complex dielectric constant of the compounds Nb-Al and Nb-Ge with A15 structure, used for determination of electronic characteristics and their variations with temperature, are measured in the 0.177-3.1 eV spectral interval at 295 and 670 K. The squares of the plasma frequencies ω 2 p of conduction electrons are obtained. In both compounds ω 2 p ∼ 19 eV 2 , which is 3.2 times less than for niobium. In this spectral interval, Nb-Al has four interband transition zones at 0.2, 0.35, 1.45, and 3.1 eV, while Nb-Ge has five such bands: 0.21, 0.32, 0.48, 0.95 and 2.0 eV. As the temperature increases ω 2 p of conduction electrons increases somewhat more than for usual metals (in both compounds), and the decrease in the analogous characteristic in the long-wave band for Nb-Ge is unusually great, preserving the sum of the changes, and there is also a significant decrease in the width of the long-wave band. These anomalies can be explained by thermal transfer of electrons from the base state of the long-wave band to the conduction band

Superconductivity in irradiated A-15 compounds at low fluences. I. Neutron-irradiated V3Si

International Nuclear Information System (INIS)

Viswanathan, R.; Caton, R.; Pande, C.S.

1978-01-01

The behavior of the superconducting transition temperature T/sub c/ of single-crystal and polycrystalline V 3 Si was investigated as a function of low-fluence neutron irradiation. It is found that the initial degradation of T/sub c/ is sample-dependent, some specimens showing no degradation in T/sub c/ up to a fluence of 2 x 10 18 n/cm 2 . This and many other earlier observations on low-fluence behavior are explained in terms of a recently proposed model of radiation damage in A-15 compounds

Synthesis and biological activity of chimeric structures derived from the cytotoxic natural compounds dolastatin 10 and dolastatin 15.

Science.gov (United States)

Poncet, J; Busquet, M; Roux, F; Pierré, A; Atassi, G; Jouin, P

1998-04-23

The natural cytotoxic compounds dolastatins 10 and 15 exhibit great similarities in structure and in their biological activity profiles. Two compounds (1 and 2) formed by interchanging the dolaisoleuine residue of dolastatin 10 and the MeVal-Pro dipeptide of dolastatin 15 were synthesized in order to evaluate the possible equivalence of these units. These compounds can be considered as chimeras of dolastatins 10 and 15 formed by the N-terminal part of the former and the C-terminal part of the latter and vice versa. Both analogues exhibited a marked decrease in their cytotoxic activity but showed similar differential cytotoxicity with regard to the cell lines assayed compared with the parent compounds. HT-29 cell line was the least sensitive one. However, this activity was in the nanomolar level and close to that of vincristine. The differences in their effect on tubulin polymerization were less pronounced. We confirmed the already known crucial role of the Dil residue in this assay. The nonequivalence of the Dil unit and the MeVal-Pro dipeptide probably reflects modification in the relative positions of the N-dimethylamino and the phenyl moieties.

Recycling of Gamma Irradiated Inner Tubes in Butyl Based Rubber Compound

International Nuclear Information System (INIS)

Karaagac, B.

2006-01-01

Crosslinked elastomeric materials, such as tyres are of great challenge concerning the environmental and ecological reasons. Ionizing radiation seems to offer unique opportunities to tackle the problem of recycling of polymers and rubbers on account of its ability to cause chain scission and/or cross-linking of polymeric materials. There is only limited amount of work reported on the irradiation-induced degradation of rubbers. Unlike the majority of the elastomers with high levels of unsaturation, butyl rubber exhibits significant degradation by ionizing radiation action. In this study, recycling of gamma irradiated inner tubes made of butyl rubber in butyl based rubber compounds was studied. Used inner tubes were irradiated with gamma rays in air at 100 and 120 kGy absorbed doses. The compatibility of irradiated inner tubes with virgin butyl rubber was first investigated. Gamma irradiated inner tube wastes were replaced with butyl rubber up to 15 phr in the compound recipe. Similar recipes were also prepared by using the same quantity of commercial butyl rubber crumbs devulcanized by conventional methods. The rheological and mechanical properties and carbon black dispersion degree for both types of compounds prepared by using inner tubes scraps and commercial butyl crumbs were measured and were compared to the values of virgin butyl rubber compound. It is well known that mechanical properties are deteriorated when rubber crumb is added to the virgin compound. It was observed that the decrease in the mechanical properties was much lower for the compounds prepared from the tubes irradiated at 120 kGy than irradiated at 100 kGy. The better mechanical properties were obtained for the compounds prepared by recycling of irradiated inner tubes at 120 kGy than the compounds prepared by using commercial butyl crumbs. Almost similar carbon black distributions were observed for the all compounds studied. It has been concluded that gamma irradiated inner tubes are compatible

The volatile compound BinBase mass spectral database.

Science.gov (United States)

Skogerson, Kirsten; Wohlgemuth, Gert; Barupal, Dinesh K; Fiehn, Oliver

2011-08-04

Volatile compounds comprise diverse chemical groups with wide-ranging sources and functions. These compounds originate from major pathways of secondary metabolism in many organisms and play essential roles in chemical ecology in both plant and animal kingdoms. In past decades, sampling methods and instrumentation for the analysis of complex volatile mixtures have improved; however, design and implementation of database tools to process and store the complex datasets have lagged behind. The volatile compound BinBase (vocBinBase) is an automated peak annotation and database system developed for the analysis of GC-TOF-MS data derived from complex volatile mixtures. The vocBinBase DB is an extension of the previously reported metabolite BinBase software developed to track and identify derivatized metabolites. The BinBase algorithm uses deconvoluted spectra and peak metadata (retention index, unique ion, spectral similarity, peak signal-to-noise ratio, and peak purity) from the Leco ChromaTOF software, and annotates peaks using a multi-tiered filtering system with stringent thresholds. The vocBinBase algorithm assigns the identity of compounds existing in the database. Volatile compound assignments are supported by the Adams mass spectral-retention index library, which contains over 2,000 plant-derived volatile compounds. Novel molecules that are not found within vocBinBase are automatically added using strict mass spectral and experimental criteria. Users obtain fully annotated data sheets with quantitative information for all volatile compounds for studies that may consist of thousands of chromatograms. The vocBinBase database may also be queried across different studies, comprising currently 1,537 unique mass spectra generated from 1.7 million deconvoluted mass spectra of 3,435 samples (18 species). Mass spectra with retention indices and volatile profiles are available as free download under the CC-BY agreement (http://vocbinbase.fiehnlab.ucdavis.edu). The BinBase

The volatile compound BinBase mass spectral database

Directory of Open Access Journals (Sweden)

Barupal Dinesh K

2011-08-01

Full Text Available Abstract Background Volatile compounds comprise diverse chemical groups with wide-ranging sources and functions. These compounds originate from major pathways of secondary metabolism in many organisms and play essential roles in chemical ecology in both plant and animal kingdoms. In past decades, sampling methods and instrumentation for the analysis of complex volatile mixtures have improved; however, design and implementation of database tools to process and store the complex datasets have lagged behind. Description The volatile compound BinBase (vocBinBase is an automated peak annotation and database system developed for the analysis of GC-TOF-MS data derived from complex volatile mixtures. The vocBinBase DB is an extension of the previously reported metabolite BinBase software developed to track and identify derivatized metabolites. The BinBase algorithm uses deconvoluted spectra and peak metadata (retention index, unique ion, spectral similarity, peak signal-to-noise ratio, and peak purity from the Leco ChromaTOF software, and annotates peaks using a multi-tiered filtering system with stringent thresholds. The vocBinBase algorithm assigns the identity of compounds existing in the database. Volatile compound assignments are supported by the Adams mass spectral-retention index library, which contains over 2,000 plant-derived volatile compounds. Novel molecules that are not found within vocBinBase are automatically added using strict mass spectral and experimental criteria. Users obtain fully annotated data sheets with quantitative information for all volatile compounds for studies that may consist of thousands of chromatograms. The vocBinBase database may also be queried across different studies, comprising currently 1,537 unique mass spectra generated from 1.7 million deconvoluted mass spectra of 3,435 samples (18 species. Mass spectra with retention indices and volatile profiles are available as free download under the CC-BY agreement (http

Solubility of some phenolic compounds in aqueous alkali metal nitrate solutions from (293.15 to 318.15) K

Energy Technology Data Exchange (ETDEWEB)

Noubigh, Adel [Laboratoire de Physico-chimie des materiaux, IPEST, BP51, 2070 La MARSA (Tunisia)], E-mail: Adel.anoubigh@ipest.rnu.tn; Cherif, Mourad [IPEIEM, Universite de Tunis-El Manar, BP244. 2096. El Manar II (Tunisia); Provost, Elise [Laboratoire Chimie et procedes, ENSTA, 32 Rue de Boulevard Victor, 75739 Paris, Cedex 15 (France); Abderrabba, Manef [Laboratoire de Physico-chimie des materiaux, IPEST, BP51, 2070 La MARSA (Tunisia)

2008-11-15

This paper is continuation of the study concerning the solubility-temperature dependence data for some phenolic compounds (PhC), contained in olive mill wastewater (OMWW), in two nitrate salts (KNO{sub 3} and NaNO{sub 3}) aqueous solutions. The solubilities of PhC were determined in the temperature ranging from (293.15 to 318.15) K. It has been observed that the solubility, in aqueous nitrate solutions, increases with increasing temperature. Results showed that alkali metal nitrate has a salting-out effect on the solubility of PhC. The effect of the anion of the electrolyte on the solubility of PhC is observed by comparing these results with values reported in the previous papers for the effect of LiCl, NaCl and KCl. For each cation, the solubilites of the phenolic compounds are higher with nitrate anion than with chloride anion. Results were interpreted in terms of the salt hydration shells and the ability of the solute to form hydrogen-bond with water. The solubility data were accurately correlated by a semi empirical equation. The standard molar Gibbs free energies of transfer of PhC ({delta}{sub tr}G{sup 0}) from pure water to aqueous solutions of the nitrate salts have been calculated from the solubility data. The decrease in solubility is correlated to the positive {delta}{sub tr}G{sup 0} value which is mainly of enthalpic origin.

Image-based compound profiling reveals a dual inhibitor of tyrosine kinase and microtubule polymerization.

Science.gov (United States)

Tanabe, Kenji

2016-04-27

Small-molecule compounds are widely used as biological research tools and therapeutic drugs. Therefore, uncovering novel targets of these compounds should provide insights that are valuable in both basic and clinical studies. I developed a method for image-based compound profiling by quantitating the effects of compounds on signal transduction and vesicle trafficking of epidermal growth factor receptor (EGFR). Using six signal transduction molecules and two markers of vesicle trafficking, 570 image features were obtained and subjected to multivariate analysis. Fourteen compounds that affected EGFR or its pathways were classified into four clusters, based on their phenotypic features. Surprisingly, one EGFR inhibitor (CAS 879127-07-8) was classified into the same cluster as nocodazole, a microtubule depolymerizer. In fact, this compound directly depolymerized microtubules. These results indicate that CAS 879127-07-8 could be used as a chemical probe to investigate both the EGFR pathway and microtubule dynamics. The image-based multivariate analysis developed herein has potential as a powerful tool for discovering unexpected drug properties.

The effects of different heat treatment annealing on structural properties of LaFe11.5Si1.5 compound

Science.gov (United States)

Norizan, Yang Nurhidayah Asnida; Din, Muhammad Faiz Md; Zamri, Wan Fathul Hakim W.; Hashim, Fakroul Ridzuan; Jusoh, Mohd Taufik; Rahman, Mohd Rashid Abdul

2018-02-01

The cubic NaZn13-type LaFe13-xSix based compounds have been studied systematically and has become one of the most interesting systems for exploring large MCE. Its magnetic properties are strongly doping dependent and provides many of advantage compare to other as magnetic materials for magnetic refrigerator application. In other to produce high quality of cubic NaZn13-type structure, the structural properties of LaFe11.5Si1.5 compounds annealed at different temperature have been investigated. The LaFe11.5Si1.5 compounds was prepared by arc melting and annealed at two different heat treatment which are 1323 K for 14 days and 1523 K for 4 hour. The powder X-ray diffraction (XRD) shows that a short time and high temperature annealing process has benefits for the formation of the NaZn13-type phase compared to a long time and low temperature annealing process. This is shown by the weight fraction of cubic NaZn13- type structure increases from 80% for low temperature annealing to 83% for high temperature annealing. At the same time, high temperature annealing increase the main structure and decrease the impurity (α-Fe and LaFeSi). Furthermore, it can be clearly seen in the Rietveld refinement results that the lattice parameter is increase at the high temperature annealing because of more cubic NaZn13 is formed at higher temperature.

Fluorescent deep-blue and hybrid white emitting devices based on a naphthalene-benzofuran compound

KAUST Repository

Yang, Xiaohui

2013-08-01

We report the synthesis, photophysics and electrochemical properties of naphthalene-benzofuran compound 1 and its application in organic light emitting devices. Fluorescent deep-blue emitting devices employing 1 as the emitting dopant embedded in 4-4′-bis(9-carbazolyl)-2,2′-biphenyl (CBP) host show the peak external quantum efficiency of 4.5% and Commission Internationale d\\'Énclairage (CIE) coordinates of (0.15, 0.07). Hybrid white devices using fluorescent blue emitting layer with 1 and a phosphorescent orange emitting layer based on an iridium-complex show the peak external quantum efficiency above 10% and CIE coordinates of (0.31, 0.37). © 2013 Published by Elsevier B.V.

APPROACH ON INTELLIGENT OPTIMIZATION DESIGN BASED ON COMPOUND KNOWLEDGE

Institute of Scientific and Technical Information of China (English)

Yao Jianchu; Zhou Ji; Yu Jun

2003-01-01

A concept of an intelligent optimal design approach is proposed, which is organized by a kind of compound knowledge model. The compound knowledge consists of modularized quantitative knowledge, inclusive experience knowledge and case-based sample knowledge. By using this compound knowledge model, the abundant quantity information of mathematical programming and the symbolic knowledge of artificial intelligence can be united together in this model. The intelligent optimal design model based on such a compound knowledge and the automatically generated decomposition principles based on it are also presented. Practically, it is applied to the production planning, process schedule and optimization of production process of a refining & chemical work and a great profit is achieved. Specially, the methods and principles are adaptable not only to continuous process industry, but also to discrete manufacturing one.

Electronic structure, superconductivity, and spin fluctuations in the A15 compounds A3B: A = V, Nb; B = Ir,Pt,Au

International Nuclear Information System (INIS)

Jarlborg, T.; Junod, A.; Peter, M.

1983-01-01

The electronic structure of six A15 compounds V 3 Ir, V 3 Pt, V 3 Au, Nb 3 Ir, Nb 3 Pt, and Nb 3 Au has been determined by means of self-consistent semirelativistic linear muffin-tin orbital band calculations. Parameters related to superconductivity such as electron-phonon coupling, transition temperature, electronic specific heat, and magnetic exchange enhancement are derived from the electronic-structure results. Generally the results obtained agree well with experimental values, with the exception of Nb 3 Pt and V 3 Au. In the former compound the density of states (DOS) has a sharp increase at E/sub F/ making the exact DOS value uncertain. In V 3 Au the high calculated T/sub c/ and the Stoner factor indicate that spin fluctuations may be limiting the T/sub c/. .AE

Analytical method for biomonitoring of endocrine-disrupting compounds (bisphenol A, parabens, perfluoroalkyl compounds and a brominated flame retardant) in human hair by liquid chromatography-tandem mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Martín, Julia; Santos, Juan Luis; Aparicio, Irene, E-mail: iaparicio@us.es; Alonso, Esteban

2016-11-16

In this paper, a method for the determination of four groups of endocrine-disrupting compounds in human hair is proposed. Target compounds were a plastic monomer (bisphenol A), three parabens commonly used as preservatives (methylparaben, ethylparaben and propylparaben), six perfluoroalkyl compounds commonly used as water, oil and dirt repellents (perfluorooctane sulfonic acid and five perfluoroalkyl carboxylic acids, with alkyl chains from four to eight carbon atoms) and a brominated flame retardant (hexabromocyclododecane). All of them are of especial concern to human health because they are utilized in many everyday products. The method is based on hair incubation with methanol/acetic acid solution (85:15, v/v), extraction with acetone for 15 min in an ultrasonic bath and analysis by liquid chromatography-electrospray-tandem mass spectrometry in negative ionization mode. Limits of quantification in hair samples ranged from 0.6 ng g{sup −1} to 6.1 ng g{sup −1}, except for hexabromocyclododecane (36 ng g{sup −1}). Recoveries were higher than 69%. Intra-day and inter-day precision, expressed as relative standard deviation, were lower than 15% and 10%, respectively. The applicability of the method was proven by analyzing the target compounds in hair samples from six volunteers. High frequencies of detection and concentrations were obtained for bisphenol A (83% of samples; concentrations up to 158 ng g{sup −1}) and parabens (100% of samples; concentrations up to 624 ng g{sup −1}). Lower concentrations were detected for the perfluoroalkyl compounds (up to 13 ng g{sup −1}). Hexabromocyclododecane was not detected. - Highlights: • Method for biomonitoring of endocrine-disrupting compounds in human hair. • Target compounds are commonly present in everyday products. • Method based on hair digestion and liquid chromatography-tandem mass spectrometry. • Good sensitivity, recoveries and precision and low matrix effect were obtained. �

Analytical method for biomonitoring of endocrine-disrupting compounds (bisphenol A, parabens, perfluoroalkyl compounds and a brominated flame retardant) in human hair by liquid chromatography-tandem mass spectrometry

International Nuclear Information System (INIS)

Martín, Julia; Santos, Juan Luis; Aparicio, Irene; Alonso, Esteban

2016-01-01

In this paper, a method for the determination of four groups of endocrine-disrupting compounds in human hair is proposed. Target compounds were a plastic monomer (bisphenol A), three parabens commonly used as preservatives (methylparaben, ethylparaben and propylparaben), six perfluoroalkyl compounds commonly used as water, oil and dirt repellents (perfluorooctane sulfonic acid and five perfluoroalkyl carboxylic acids, with alkyl chains from four to eight carbon atoms) and a brominated flame retardant (hexabromocyclododecane). All of them are of especial concern to human health because they are utilized in many everyday products. The method is based on hair incubation with methanol/acetic acid solution (85:15, v/v), extraction with acetone for 15 min in an ultrasonic bath and analysis by liquid chromatography-electrospray-tandem mass spectrometry in negative ionization mode. Limits of quantification in hair samples ranged from 0.6 ng g"−"1 to 6.1 ng g"−"1, except for hexabromocyclododecane (36 ng g"−"1). Recoveries were higher than 69%. Intra-day and inter-day precision, expressed as relative standard deviation, were lower than 15% and 10%, respectively. The applicability of the method was proven by analyzing the target compounds in hair samples from six volunteers. High frequencies of detection and concentrations were obtained for bisphenol A (83% of samples; concentrations up to 158 ng g"−"1) and parabens (100% of samples; concentrations up to 624 ng g"−"1). Lower concentrations were detected for the perfluoroalkyl compounds (up to 13 ng g"−"1). Hexabromocyclododecane was not detected. - Highlights: • Method for biomonitoring of endocrine-disrupting compounds in human hair. • Target compounds are commonly present in everyday products. • Method based on hair digestion and liquid chromatography-tandem mass spectrometry. • Good sensitivity, recoveries and precision and low matrix effect were obtained. • Method was successfully

Building Asphalt Pavement with SBS-based Compound Added Using a Dry Process in Greenland

DEFF Research Database (Denmark)

Lee, Hosin; Kim, Yongjoo; Geisler, Nivi

2009-01-01

PMA where it is formulated to melt and blend with asphalt quickly during a batch mixing process. The main objectives of this study are to (1) build asphalt pavement using asphalt mixtures with SBS-based compound added using a “dry” process at the batch plant and (2) evaluate its performance under......-based compound seemed to affect the asphalt mix to become more flexible under the heavy loads. By adding SBS-based compound to asphalt mixtures using a “dry” process, it is expected that the pavement would become more resistant to rutting than a typical asphalt mixture used in Greenland while enduring its arctic...

A new disordering mechanism in A15 type compounds submitted to low temperature irradiation or to quenching from high temperatures

International Nuclear Information System (INIS)

Fluekiger, R.

1984-05-01

A new diffusion mechanism describing the changes of the long range order parameter in A15 type compounds after both quenching from high temperatures or low temperature irradiation with high energy particles is presented. It is based on the occupation of nonequilibrium or 'virtual' sites centered halfway between two neighbouring A atoms on 6c sites, arising from the instability of a single 6c vacancy recently found by Welch and coworkers by pair potential calculations. After low temperature irradiation, the occupation of this interstitial site creates the necessary conditions for A B site exchanges over several interatomic distances by focused replacement collision sequences. Due to the occupation of a certain concentration of virtual sites, atomic 'overlapping' is not only possible between A atoms on the chains or between A and B atoms (due to deviations from perfect ordering),but also between B atoms on BBB sequences. The latter are retained after low temperature irradiation only and are responsible for the observed lattice expansion and static displacement. (orig.) [de

Stability and electronic structure of Zr-based ternary metallic glasses and relevant compounds

International Nuclear Information System (INIS)

Hasegawa, M.; Soda, K.; Sato, H.; Suzuki, T.; Taketomi, T.; Takeuchi, T.; Kato, H.; Mizutani, U.

2007-01-01

The electronic structure of the Zr-based metallic glasses has been investigated by theoretical and experimental approaches. One approach is band calculations of the Zr 2 Ni (Zr 66.7 Ni 33.3 ) compound to investigate the electronic structure of the Zr 66.7 Ni 33.3 metallic glass (ΔT x = 0 K) of which the local atomic structure is similar to that of the Zr 2 Ni compound. The other is photoemission spectroscopy of the Zr 50 Cu 35 Al 15 bulk metallic glass (BMG) (ΔT x = 69 K). Here ΔT x = T x - T g where T x and T g are crystallization and glass transition temperature, respectively. Both results and previous ones on the Zr 55 Cu 30 Ni 5 Al 10 BMG indicate that there is a pseudogap at the Fermi level in the electronic structure of these Zr-based metallic glasses, independent of the value of the ΔT x . This implies that the pseudogap at the Fermi level is one of the factors that stabilize the glass phase of Zr-based metallic glasses

Image-based compound profiling reveals a dual inhibitor of tyrosine kinase and microtubule polymerization

OpenAIRE

Tanabe, Kenji

2016-01-01

Small-molecule compounds are widely used as biological research tools and therapeutic drugs. Therefore, uncovering novel targets of these compounds should provide insights that are valuable in both basic and clinical studies. I developed a method for image-based compound profiling by quantitating the effects of compounds on signal transduction and vesicle trafficking of epidermal growth factor receptor (EGFR). Using six signal transduction molecules and two markers of vesicle trafficking, 570...

Design of cinnamaldehyde amino acid Schiff base compounds based on the quantitative structure–activity relationship

Science.gov (United States)

Hui Wang; Mingyue Jiang; Shujun Li; Chung-Yun Hse; Chunde Jin; Fangli Sun; Zhuo Li

2017-01-01

Cinnamaldehyde amino acid Schiff base (CAAS) is a new class of safe, bioactive compounds which could be developed as potential antifungal agents for fungal infections. To design new cinnamaldehyde amino acid Schiff base compounds with high bioactivity, the quantitative structure–activity relationships (QSARs) for CAAS compounds against Aspergillus niger (A. niger) and...

Schiff bases derived from 1-aminoanthraquinone: a new class of analgesic compounds

International Nuclear Information System (INIS)

Fareed, G.; Rizwan, G.H.; Fareed, N.

2017-01-01

A series of Schiff bases 1-17 were synthesised by way of a facile condensation between 1-amino-anthraquinone with a variety of carbonyl compounds in the presence of a catalytic amount of dodeca-tungstosilicic acid/P 2O5 under solvent free conditions at room temperature. These were charachterised by1H- and 13C-NMR, LCMS, FTIR and elemental analyses. All the compounds were screened for their analgesic activity using hot plate thermal stimuli method at dose of 10 and 30 mg/kg. Diclofenac sodium was used as a reference drug. All the compounds at dose of 10 and 30 mg/kg body weight showed the significant (p<0.05) increase in latency time as compared to control (normal saline). Compound 5 showed excellent activity after 120 min of drug administration (10 mg/kg) of body weight. Compound 10 was found to be potent (10.48+-1.19s, 11.27+-1.2s and 10.24+-1.9s) at dose of 30 mg/kg at 30, 60 and 120 min, respectively when compared to the standard drug. Compound 6 (10.13+-0.4s) was also found to be an excellent analgesic compound at a dose of 30 mg/kg at 120 min. However, the studies on analgesic activity revealed that some of the target compounds may be strong candidates as an analgesic drug. (author)

Structure and properties of alloys of A15 type compounds with carbon

International Nuclear Information System (INIS)

Savitskij, E.M.; Efimov, Yu.V.; Myasnikova, E.A.

1983-01-01

Microstructure and some properties of the alloys on the base of the phases of A15 type in the V-Si-C, Nb-Si-C, Nb-Sn-C, Nb-Al-C, Nb-Ga-C, V-Ga-C ternary systems are investigated. It is established that in the niobium-rich corners of the A-B-C ternary systems the new ternary conpounds do not form, as a rule, bUt the wide ranges of threephase equilibrium A-A 3 B-C exist. New ternary phases with A15 type structure stabilized with carbon are established only in the Nb-Si-C and V-Al-C systems. Alloying with carbon results in sharp refining of structural components of stable and metastable alloys, promotes transition of the alloys into amorphous state at super fast cooling of the melts as well as increases stability of metastable state of the alloys against tempering. After super fast quenching and tempering Tsub(c) of the ternary alloys close to the A15 phases exceed Tsub(c) of equilibrium samples

Compounds in dictionary-based Cross-language information retrieval_revised

Directory of Open Access Journals (Sweden)

2002-01-01

Full Text Available Compound words form an important part of natural language. From the cross-lingual information retrieval (CLIR point of view it is important that many natural languages are highly productive with compounds, and translation resources cannot include entries for all compounds. Also, compounds are often content bearing words in a sentence. In Swedish, German and Finnish roughly one tenth of the words in a text prepared for information retrieval purposes are compounds. Important research questions concerning compound handling in dictionary-based cross-language information retrieval are 1 compound splitting into components, 2 normalisation of components, 3 translation of components and 4 query structuring for compounds and their components in the target language. The impact of compound processing on the performance of the cross-language information retrieval process is evaluated in this study and the results indicate that the effect is clearly positive.

Modified solution calorimetry approach for determination of vaporization and sublimation enthalpies of branched-chain aliphatic and alkyl aromatic compounds at T = 298.15 K

International Nuclear Information System (INIS)

Varfolomeev, Mikhail A.; Novikov, Vladimir B.; Nagrimanov, Ruslan N.; Solomonov, Boris N.

2015-01-01

Highlights: • Solution enthalpies of 18 branching-chain alkyl aromatic and aliphatic compounds in cyclohexane were measured. • Group contributions to the enthalpy of solvation due to branching and substitution in carbon chain were evaluated. • Modified solution calorimetry based approach for determination of vaporization/sublimation enthalpies was proposed. • This approach provides vaporization/sublimation enthalpies directly at T = 298.15 K. • Vaporization/sublimation enthalpies of 35 branched-chain alkyl aromatic and aliphatic compounds were determined. - Abstract: The enthalpies of solution, solvation and vaporization/sublimation are interrelated values combined in the simplest thermodynamic circle. Hence, experimental determination of vaporization/sublimation enthalpy can be substituted by experimentally simpler determination of solution enthalpy when solvation enthalpy is known. Previously it was found that solvation enthalpies of a wide range of unbranched aliphatic and aromatic solutes in saturated hydrocarbons are in good linear correlation with their molar refraction values. This allows to estimate the vaporization/sublimation enthalpy of any unbranched organic compound from its solution enthalpy in saturated hydrocarbon and molar refraction. In the present work this approach was modified for determination of vaporization/sublimation enthalpy of branched-chain alkyl aromatic and aliphatic compounds. Group contributions to the enthalpy of solvation due to the branching of carbon chain were evaluated. Enthalpies of solution at infinite dilution of 18 branched-chain aliphatic and alkyl aromatic compounds were measured at T = 298.15 K. Vaporization/sublimation enthalpies for 35 branched aliphatic and alkyl aromatic compounds were determined by using modified solution calorimetry approach. These values are in good agreement with available literature data on vaporization/sublimation enthalpies obtained by conventional methods.

Multiresponse optimization of a UPLC method for the simultaneous determination of tryptophan and 15 tryptophan-derived compounds using a Box-Behnken design with a desirability function.

Science.gov (United States)

Setyaningsih, Widiastuti; Saputro, Irfan E; Carrera, Ceferino A; Palma, Miguel; Barroso, Carmelo G

2017-06-15

A Box-Behnken design was used in conjunction with multiresponse optimization based on the desirability function to carry out the simultaneous separation of tryptophan and 15 derivatives by Ultra Performance Liquid Chromatography. The gradient composition of the mobile phase and the flow rate were optimized with respect to the resolution of severely overlapping chromatographic peaks and the total run time. Two different stationary phases were evaluated (hybrid silica and a solid-core-based C 18 column). The methods were validated and a suitable sensitivity was found for all compounds in the concentration range 1-100μgL -1 (R 2 >0.999). High levels of repeatability and intermediate precision (CV less than 0.25% and 1.7% on average for the retention time and the signal area, respectively) were obtained. The new method was applied to the determination tryptophan and its derivatives in black pigmented glutinous and non-glutinous rice grain samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis of 15N-enriched urea (CO(15NH22 from 15NH3, CO, and S in a discontinuous process

Directory of Open Access Journals (Sweden)

C. R. Sant Ana Filho

2012-12-01

Full Text Available CO(15NH22 enriched with the stable isotope 15N was synthesized based on a reaction involving CO, 15NH3, and S in the presence of CH3OH. The method differs from the industrial method; a stainless steel reactor internally lined with polytetrafluoroethylene (PTFE was used in a discontinuous process under low pressure and temperature. The yield of the synthesis was evaluated as a function of the parameters: the amount of reagents, reaction time, addition of H2S, liquid solution and reaction temperature. The results showed that under optimum conditions (1.36, 4.01, and 4.48 g of 15NH3, CO, and S, respectively, 40 ml CH3OH, 40 mg H2S, 100 ºC and 120 min of reaction 1.82 g (yield 76.5% of the compound was obtained per batch. The synthesized CO(15NH22 contained 46.2% N, 0.55% biuret, melting point of 132.55 ºC and did not exhibit isotopic fractionation. The production cost of CO(15NH22 with 90.0 at. % 15N was US$ 238.60 per gram.

Pericocins A-D, New Bioactive Compounds from Periconia sp.

Science.gov (United States)

Wu, Yue-Hua; Xiao, Gao-Keng; Chen, Guo-Dong; Wang, Chuan-Xi; Hu, Dan; Lian, Yun-Yang; Lin, Feng; Guo, Liang-Dong; Yao, Xin-Sheng; Gao, Hao

2015-12-01

One new dihydroisocoumarin, pericocin A (1), one new chromone, pericocin B (2), and two new α-pyrone derivatives, pericocins C-D (3-4), together with two known compounds, 3-(2-oxo-2H-pyran-6-yl)propanoic acid (5) and (E)-3-(2-oxo-2H-pyran-6-yl)acrylic acid (6), were isolated from the culture of the endolichenic fungus Periconia sp.. Their structures were elucidated by spectroscopic methods. All these compounds are derived from the polyketone biosynthetic pathway. Compound 1 was obtained as a mixture of enantiomers. The antimicrobial activity of compounds 1-5 was tested against Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Candida albicans. Compounds 1-5 showed moderate antimicrobial activity against A. niger and weak activity against C. albicans.

Micro-arc oxidation of Ti-15Zr-based alloys for osseointegrative implants

International Nuclear Information System (INIS)

Correa, Diego Rafael Nespeque; Rocha, Luis Augusto; Doi, Hisashi; Tsutsumi, Yusuke; Hanawa, Takao

2016-01-01

Full text: Micro-arc oxidation (MAO) is well-known as low-cost coating technique which can produce porous structure in valve metals [1]. Studies have indicated that MAOcoatings are suitable for improve biofunctionalization of Ti-based implants by bioactive ions incorporation in the oxide layer [2]. This work aims to evaluate the characteristics of the MAO-coating in recent developed biomedical Ti-15Zr-based alloys in order to use as osseointegrative implants. Ti-15Zr-xMo (x = 0, 5, 10 and 15 % wt.) alloys were produced by argon arc-melting and molded in a centrifugal casting machine. MAO treatment were performed in disks (ϕ 8 mm x 1.5 mm), at room temperature, with a 304 stainless steel plate as counter electrode. Electrolyte was composed by 0.15 M calcium acetate and 0.10 M calcium glycerophosphate. The electrodes were connected to a DC power supply, and applied a density current of 311 A/m 2 , for 10 min, with voltages of 300, 350 and 400 V. Morphology, thickness, composition and crystal structure of the oxide layer were evaluated by SEM, XRF and XRD techniques. A typical porous layer was produced in all surfaces, being the porosity, porous size and thickness increased with the voltage. The composition of the oxide layer indicated Ca and P incorporation, being the concentration increased with the voltage applied. The XRD patterns do not exhibited peaks from oxides compounds, but only peaks from bulk-Ti phases. The results showed that the bioactive coatings were successfully growth in the Ti-15Zr-based alloys, being suitable for osseointegrative implants. References: [1] Hanawa, T. Japanese dental Science Review 46, 93-101, 2010; [2] Tsutsumi, Y. et al. Metals 6, 76-85, 2016. (author)

Micro-arc oxidation of Ti-15Zr-based alloys for osseointegrative implants

Energy Technology Data Exchange (ETDEWEB)

Correa, Diego Rafael Nespeque; Rocha, Luis Augusto [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Bauru, SP (Brazil); Doi, Hisashi; Tsutsumi, Yusuke; Hanawa, Takao [Tokyo Medical and Dental University (Japan)

2016-07-01

Full text: Micro-arc oxidation (MAO) is well-known as low-cost coating technique which can produce porous structure in valve metals [1]. Studies have indicated that MAOcoatings are suitable for improve biofunctionalization of Ti-based implants by bioactive ions incorporation in the oxide layer [2]. This work aims to evaluate the characteristics of the MAO-coating in recent developed biomedical Ti-15Zr-based alloys in order to use as osseointegrative implants. Ti-15Zr-xMo (x = 0, 5, 10 and 15 % wt.) alloys were produced by argon arc-melting and molded in a centrifugal casting machine. MAO treatment were performed in disks (ϕ 8 mm x 1.5 mm), at room temperature, with a 304 stainless steel plate as counter electrode. Electrolyte was composed by 0.15 M calcium acetate and 0.10 M calcium glycerophosphate. The electrodes were connected to a DC power supply, and applied a density current of 311 A/m{sup 2}, for 10 min, with voltages of 300, 350 and 400 V. Morphology, thickness, composition and crystal structure of the oxide layer were evaluated by SEM, XRF and XRD techniques. A typical porous layer was produced in all surfaces, being the porosity, porous size and thickness increased with the voltage. The composition of the oxide layer indicated Ca and P incorporation, being the concentration increased with the voltage applied. The XRD patterns do not exhibited peaks from oxides compounds, but only peaks from bulk-Ti phases. The results showed that the bioactive coatings were successfully growth in the Ti-15Zr-based alloys, being suitable for osseointegrative implants. References: [1] Hanawa, T. Japanese dental Science Review 46, 93-101, 2010; [2] Tsutsumi, Y. et al. Metals 6, 76-85, 2016. (author)

Effect of structural packing on the luminescence properties in tungsten bronze compounds M{sub 2}KNb{sub 5}O{sub 15} (M=Ca, Sr, Ba)

Energy Technology Data Exchange (ETDEWEB)

Yin Xin; Shi Liu [State Key Laboratory of High Performance Ceramics and Superfine Microstructures and CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Wei Ang, E-mail: iamawei@njupt.edu.cn [Key Laboratory for Organic Electronics and Information Displays, 9 Wenyuan Road, Nanjing 210046 (China); Wan Dongyun; Wang Yaoming [State Key Laboratory of High Performance Ceramics and Superfine Microstructures and CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Huang Fuqiang, E-mail: huangfq@mail.sic.ac.cn [State Key Laboratory of High Performance Ceramics and Superfine Microstructures and CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)

2012-08-15

Tungsten bronze compounds M{sub 2}KNb{sub 5}O{sub 15} (M=Ca, Sr, Ba) were successfully synthesized, and the luminescence properties were investigated. Among the three compounds, Ca{sub 2}KNb{sub 5}O{sub 15} showed an obviously broad band of host luminescence at 460 nm with exciting at 269 nm. By doping Eu{sup 3+} into the M sites, Ca{sub 2}KNb{sub 5}O{sub 15}:Eu{sup 3+} displayed strong red emission from Eu{sup 3+} ions characteristic transitions, nearly four times higher than Sr{sub 2}KNb{sub 5}O{sub 15}:Eu{sup 3+} and seven times higher than Ba{sub 2}KNb{sub 5}O{sub 15}:Eu{sup 3+}. Crystal packing factor (PF) was introduced to account for this luminescence difference, lower PF being correlated to higher luminescence intensity for perovskite-related structure. Both the as-prepared compounds and the literature examples were proved to fit this correlation. This can be explained through the influence of the structural packing on the environment distortion and crystal field splitting of the doping site. - Graphical abstract: Tungsten bronze compounds M{sub 2}KNb{sub 5}O{sub 15} (M=Ca, Sr, Ba) show the dependence of luminescence properties on structural packing, among which Ca{sub 2}KNb{sub 5}O{sub 15} has the superior luminescence. Highlights: Black-Right-Pointing-Pointer Tungsten bronze compounds were synthesized by solid state reaction. Black-Right-Pointing-Pointer Ca{sub 2}KNb{sub 5}O{sub 15} displayed remarkably blue host luminescence. Black-Right-Pointing-Pointer Ca{sub 2}KNb{sub 5}O{sub 15}:Eu{sup 3+} showed more intense red emission than M{sub 2}KNb{sub 5}O{sub 15}:Eu{sup 3+} (M=Sr, Ba). Black-Right-Pointing-Pointer The relationship between crystal packing factor and luminescence was obtained.

Structure-Based Virtual Screening of Commercially Available Compound Libraries.

Science.gov (United States)

Kireev, Dmitri

2016-01-01

Virtual screening (VS) is an efficient hit-finding tool. Its distinctive strength is that it allows one to screen compound libraries that are not available in the lab. Moreover, structure-based (SB) VS also enables an understanding of how the hit compounds bind the protein target, thus laying ground work for the rational hit-to-lead progression. SBVS requires a very limited experimental effort and is particularly well suited for academic labs and small biotech companies that, unlike pharmaceutical companies, do not have physical access to quality small-molecule libraries. Here, we describe SBVS of commercial compound libraries for Mer kinase inhibitors. The screening protocol relies on the docking algorithm Glide complemented by a post-docking filter based on structural protein-ligand interaction fingerprints (SPLIF).

Acute organophosphorus compound poisoning in cattle: A case report

African Journals Online (AJOL)

A case of an acute organophosphorus compound, GOLDFLEECE poisoning involving 39 cattle at Abubakar Tafawa Balewa University, Bauchi is reported. The animals were overexposed to the compound following routine tick spray. Within 15 minutes after the spray of the compound, 26 animals were recumbent showing ...

Amberlyst-15: An Efficient and reusable heterogeneous catalyst for the synthesis of β-amino carbonyl compounds

Directory of Open Access Journals (Sweden)

Pathakota Venkata Ramana

2015-12-01

Full Text Available A simple and efficient method has been developed for the synthesis of β-amino carbonyl compounds from aromatic ketones, aldehydes and amines by Mannich reaction in the presence of amberlyst-15 as a reusable heterogeneous catalyst at room temperature under solvent-free conditions. The noteworthy advantages of the present method are short reaction times, good product yields, simple procedures and use of non-toxic catalyst.

FilTer BaSe: A web accessible chemical database for small compound libraries.

Science.gov (United States)

Kolte, Baban S; Londhe, Sanjay R; Solanki, Bhushan R; Gacche, Rajesh N; Meshram, Rohan J

2018-03-01

Finding novel chemical agents for targeting disease associated drug targets often requires screening of large number of new chemical libraries. In silico methods are generally implemented at initial stages for virtual screening. Filtering of such compound libraries on physicochemical and substructure ground is done to ensure elimination of compounds with undesired chemical properties. Filtering procedure, is redundant, time consuming and requires efficient bioinformatics/computer manpower along with high end software involving huge capital investment that forms a major obstacle in drug discovery projects in academic setup. We present an open source resource, FilTer BaSe- a chemoinformatics platform (http://bioinfo.net.in/filterbase/) that host fully filtered, ready to use compound libraries with workable size. The resource also hosts a database that enables efficient searching the chemical space of around 348,000 compounds on the basis of physicochemical and substructure properties. Ready to use compound libraries and database presented here is expected to aid a helping hand for new drug developers and medicinal chemists. Copyright © 2017 Elsevier Inc. All rights reserved.

Ligand efficiency based approach for efficient virtual screening of compound libraries.

Science.gov (United States)

Ke, Yi-Yu; Coumar, Mohane Selvaraj; Shiao, Hui-Yi; Wang, Wen-Chieh; Chen, Chieh-Wen; Song, Jen-Shin; Chen, Chun-Hwa; Lin, Wen-Hsing; Wu, Szu-Huei; Hsu, John T A; Chang, Chung-Ming; Hsieh, Hsing-Pang

2014-08-18

Here we report for the first time the use of fit quality (FQ), a ligand efficiency (LE) based measure for virtual screening (VS) of compound libraries. The LE based VS protocol was used to screen an in-house database of 125,000 compounds to identify aurora kinase A inhibitors. First, 20 known aurora kinase inhibitors were docked to aurora kinase A crystal structure (PDB ID: 2W1C); and the conformations of docked ligand were used to create a pharmacophore (PH) model. The PH model was used to screen the database compounds, and rank (PH rank) them based on the predicted IC50 values. Next, LE_Scale, a weight-dependant LE function, was derived from 294 known aurora kinase inhibitors. Using the fit quality (FQ = LE/LE_Scale) score derived from the LE_Scale function, the database compounds were reranked (PH_FQ rank) and the top 151 (0.12% of database) compounds were assessed for aurora kinase A inhibition biochemically. This VS protocol led to the identification of 7 novel hits, with compound 5 showing aurora kinase A IC50 = 1.29 μM. Furthermore, testing of 5 against a panel of 31 kinase reveals that it is selective toward aurora kinase A & B, with <50% inhibition for other kinases at 10 μM concentrations and is a suitable candidate for further development. Incorporation of FQ score in the VS protocol not only helped identify a novel aurora kinase inhibitor, 5, but also increased the hit rate of the VS protocol by improving the enrichment factor (EF) for FQ based screening (EF = 828), compared to PH based screening (EF = 237) alone. The LE based VS protocol disclosed here could be applied to other targets for hit identification in an efficient manner. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

PHOTOELECTRON-SPECTROSCOPY STUDY OF THE ELECTRONIC-STRUCTURE OF THE INCOMMENSURATE INTERGROWTH COMPOUNDS (SBS)(1.15)(TIS2)(N) WITH N=1, 2

NARCIS (Netherlands)

REN, Y; HAAS, C; WIEGERS, GA

1995-01-01

The electronic structure of the inorganic misfit-layer compounds (SbS)(1.15)(TiS2)(n) (n = 1,2) has been investigated using x-ray photoemission spectroscopy (XPS), ultraviolet photoemission spectroscopy (UPS) and x-ray absorption spectroscopy (XAS). These compounds are built of alternating modulated

Synthesis of puric bases labelled with carbon 14 and nitrogen 15

International Nuclear Information System (INIS)

Lamorre, Yves

1975-01-01

In this report for graduation in organic chemistry engineering, the author reports the synthesis of adenine 14 C-2 et 14 C-6 by two different chemical ways from two derivatives of imidazole. He has used adenine 14 C-6 to obtain hypoxanthine 14 C-6, and then, by enzymatic processing, uric acid 14 C-6. He reports the study of the production of guanine 14 C-2 by cyclization of silylated derivative of imidazole with the carbon 14 C sulphur. However, a method of complete synthesis of this same compound revealed to be more practical. This complete synthesis way allowed the labelling of guanine in positions 1, 2 and 3 by the 96 per cent isotopic nitrogen. Nitrogen in positions 7 and 9 could have been labelled by the same way from the ethyl cyanoacetate 15 N and from the sodium nitrite 15 N. The study of the mass spectrum of these compounds labelled with nitrogen 15 N allowed most of fragments obtained during this analysis to be identified [fr

Method of plasma etching Ga-based compound semiconductors

Science.gov (United States)

Qiu, Weibin; Goddard, Lynford L.

2012-12-25

A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent to the process chamber. The process chamber contains a sample comprising a Ga-based compound semiconductor. The sample is in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. The method includes flowing SiCl.sub.4 gas into the chamber, flowing Ar gas into the chamber, and flowing H.sub.2 gas into the chamber. RF power is supplied independently to the source electrode and the platen. A plasma is generated based on the gases in the process chamber, and regions of a surface of the sample adjacent to one or more masked portions of the surface are etched to create a substantially smooth etched surface including features having substantially vertical walls beneath the masked portions.

Development of a 15 K hydrogen-based sorption cooler

NARCIS (Netherlands)

Burger, Johannes Faas; Holland, Herman J.; Meijer, R.J.; Linder, M.; ter Brake, Hermanus J.M.

2010-01-01

At the University of Twente, a 15 K hydrogen-based sorption cooler is under development, which has no moving parts and, therefore, is essentially vibration-free. Moreover, it has the potential of a very long life. Although the cooler may operate standalone, it is designed to precool a helium-based

BitterSweetForest: A random forest based binary classifier to predict bitterness and sweetness of chemical compounds

Science.gov (United States)

Banerjee, Priyanka; Preissner, Robert

2018-04-01

Taste of a chemical compounds present in food stimulates us to take in nutrients and avoid poisons. However, the perception of taste greatly depends on the genetic as well as evolutionary perspectives. The aim of this work was the development and validation of a machine learning model based on molecular fingerprints to discriminate between sweet and bitter taste of molecules. BitterSweetForest is the first open access model based on KNIME workflow that provides platform for prediction of bitter and sweet taste of chemical compounds using molecular fingerprints and Random Forest based classifier. The constructed model yielded an accuracy of 95% and an AUC of 0.98 in cross-validation. In independent test set, BitterSweetForest achieved an accuracy of 96 % and an AUC of 0.98 for bitter and sweet taste prediction. The constructed model was further applied to predict the bitter and sweet taste of natural compounds, approved drugs as well as on an acute toxicity compound data set. BitterSweetForest suggests 70% of the natural product space, as bitter and 10 % of the natural product space as sweet with confidence score of 0.60 and above. 77 % of the approved drug set was predicted as bitter and 2% as sweet with a confidence scores of 0.75 and above. Similarly, 75% of the total compounds from acute oral toxicity class were predicted only as bitter with a minimum confidence score of 0.75, revealing toxic compounds are mostly bitter. Furthermore, we applied a Bayesian based feature analysis method to discriminate the most occurring chemical features between sweet and bitter compounds from the feature space of a circular fingerprint.

Influence of the substitution of Ni for Fe on the microstructure evolution and magnetic phase transition in La(Fe1−xNix)11.5Si1.5 compounds

International Nuclear Information System (INIS)

Sun, Song; Ye, Rongchang; Long, Yi

2013-01-01

Graphical abstract: M–T curves show that all the compounds undergo a ferromagnetic–paramagnetic magnetic phase transition process. Besides, the Curie temperature T c of La(Fe 1−x Ni x ) 11.5 Si 1.5 (x = 0, 0.01, 0.02, 0.03) compounds increase monotonously from 195 K to 219 K when Ni content x varies from 0 to 0.03. Highlights: ► We substituted Fe by new element Ni in La(Fe 1−x Ni x ) 11.5 Si 1.5 compounds. ► The microstructure evolution, magnetic phase transition and Curie temperature of La(Fe 1−x Ni x ) 11.5 Si 1.5 compounds were investigated. ► The small substitution of Ni for Fe in La(Fe 1−x Ni x ) 11.5 Si 1.5 compounds enhances the formation of 1:13 phase and helps the elimination of impurity phase significantly. ► The Curie temperature T C of La(Fe 1−x Ni x ) 11.5 Si 1.5 compounds increase monotonously from 195 K to 219 K when x varies from 0 to 0.03. - Abstract: The influence of Ni substitution on the microstructure evolution and magnetic phase transition has been investigated in La(Fe 1−x Ni x ) 11.5 Si 1.5 (x = 0, 0.01, 0.02, 0.03) compounds. Results show that partial substitution of Ni for Fe in La(Fe 1−x Ni x ) 11.5 Si 1.5 (x = 0, 0.01, 0.02, 0.03) alloys promotes fining of the as-cast microstructure. Besides, the formation of 1:13 phase and the elimination of impurity phases is facilitated significantly when annealed at 1373 K for 5 days. Large amounts of inhomogeneities are present in the annealed LaFe 11.5 Si 1.5 alloy. While almost single 1:13 phase is obtained in La(Fe 1−x Ni x ) 11.5 Si 1.5 (x = 0.02, 0.03) alloys. Moreover, the Curie temperature T C of La(Fe 1−x Ni x ) 11.5 Si 1.5 (x = 0, 0.01, 0.02, 0.03) compounds increase monotonously from 195 K to 219 K when Ni content x varies from 0 to 0.03.

Catalytic Steam Reforming of Toluene as a Model Compound of Biomass Gasification Tar Using Ni-CeO2/SBA-15 Catalysts

Directory of Open Access Journals (Sweden)

Erik Dahlquist

2013-07-01

Full Text Available Nickel supported on SBA-15 doped with CeO2 catalysts (Ni-CeO2/SBA-15 was prepared, and used for steam reforming of toluene which was selected as a model compound of biomass gasification tar. A fixed-bed lab-scale set was designed and employed to evaluate the catalytic performances of the Ni-CeO2/SBA-15 catalysts. Experiments were performed to reveal the effects of several factors on the toluene conversion and product gas composition, including the reaction temperature, steam/carbon (S/C ratio, and CeO2 loading content. Moreover, the catalysts were subjected to analysis of their carbon contents after the steam reforming experiments, as well as to test the catalytic stability over a long experimental period. The results indicated that the Ni-CeO2/SBA-15 catalysts exhibited promising capabilities on the toluene conversion, anti-coke deposition and catalytic stability. The toluene conversion reached as high as 98.9% at steam reforming temperature of 850 °C and S/C ratio of 3 using the Ni-CeO2(3wt%/SBA-15 catalyst. Negligible coke formation was detected on the used catalyst. The gaseous products mainly consisted of H2 and CO, together with a little CO2 and CH4.

Identification of potential inhibitors based on compound proposal contest: Tyrosine-protein kinase Yes as a target.

Science.gov (United States)

Chiba, Shuntaro; Ikeda, Kazuyoshi; Ishida, Takashi; Gromiha, M Michael; Taguchi, Y-H; Iwadate, Mitsuo; Umeyama, Hideaki; Hsin, Kun-Yi; Kitano, Hiroaki; Yamamoto, Kazuki; Sugaya, Nobuyoshi; Kato, Koya; Okuno, Tatsuya; Chikenji, George; Mochizuki, Masahiro; Yasuo, Nobuaki; Yoshino, Ryunosuke; Yanagisawa, Keisuke; Ban, Tomohiro; Teramoto, Reiji; Ramakrishnan, Chandrasekaran; Thangakani, A Mary; Velmurugan, D; Prathipati, Philip; Ito, Junichi; Tsuchiya, Yuko; Mizuguchi, Kenji; Honma, Teruki; Hirokawa, Takatsugu; Akiyama, Yutaka; Sekijima, Masakazu

2015-11-26

A search of broader range of chemical space is important for drug discovery. Different methods of computer-aided drug discovery (CADD) are known to propose compounds in different chemical spaces as hit molecules for the same target protein. This study aimed at using multiple CADD methods through open innovation to achieve a level of hit molecule diversity that is not achievable with any particular single method. We held a compound proposal contest, in which multiple research groups participated and predicted inhibitors of tyrosine-protein kinase Yes. This showed whether collective knowledge based on individual approaches helped to obtain hit compounds from a broad range of chemical space and whether the contest-based approach was effective.

Giant negative thermal expansion in NaZn13-type La(Fe, Si, Co)13 compounds.

Science.gov (United States)

Huang, Rongjin; Liu, Yanying; Fan, Wei; Tan, Jie; Xiao, Furen; Qian, Lihe; Li, Laifeng

2013-08-07

La(Fe, Si)13-based compounds are well-known magnetocaloric materials, which show a pronounced negative thermal expansion (NTE) around the Curie temperature but have not been considered as NTE materials for industrial applications. The NaZn13-type LaFe13-xSix and LaFe11.5-xCoxSi1.5 compounds were synthesized, and their linear NTE properties were investigated. By optimizing the chemical composition, the sharp volume change in La(Fe, Si)13-based compounds was successfully modified into continuous expansion. By increasing the amount of Co dopant in LaFe11.5-xCoxSi1.5, the NTE shifts toward a higher temperature region, and also the NTE operation-temperature window becomes broader. Typically, the linear NTE coefficient identified in the LaFe10.5Co1.0Si1.5 compound reaches as much as -26.1 × 10(-6) K(-1), with an operation-temperature window of 110 K from 240 to 350 K, which includes room temperature. Such control of the specific composition and the NTE properties of La(Fe, Si)13-based compounds suggests their potential application as NTE materials.

Translation of Japanese Noun Compounds at Super-Function Based MT System

Science.gov (United States)

Zhao, Xin; Ren, Fuji; Kuroiwa, Shingo

Noun compounds are frequently encountered construction in nature language processing (NLP), consisting of a sequence of two or more nouns which functions syntactically as one noun. The translation of noun compounds has become a major issue in Machine Translation (MT) due to their frequency of occurrence and high productivity. In our previous studies on Super-Function Based Machine Translation (SFBMT), we have found that noun compounds are very frequently used and difficult to be translated correctly, the overgeneration of noun compounds can be dangerous as it may introduce ambiguity in the translation. In this paper, we discuss the challenges in handling Japanese noun compounds in an SFBMT system, we present a shallow method for translating noun compounds by using a word level translation dictionary and target language monolingual corpus.

Performance Evaluation of Frequency Transform Based Block Classification of Compound Image Segmentation Techniques

Science.gov (United States)

Selwyn, Ebenezer Juliet; Florinabel, D. Jemi

2018-04-01

Compound image segmentation plays a vital role in the compression of computer screen images. Computer screen images are images which are mixed with textual, graphical, or pictorial contents. In this paper, we present a comparison of two transform based block classification of compound images based on metrics like speed of classification, precision and recall rate. Block based classification approaches normally divide the compound images into fixed size blocks of non-overlapping in nature. Then frequency transform like Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) are applied over each block. Mean and standard deviation are computed for each 8 × 8 block and are used as features set to classify the compound images into text/graphics and picture/background block. The classification accuracy of block classification based segmentation techniques are measured by evaluation metrics like precision and recall rate. Compound images of smooth background and complex background images containing text of varying size, colour and orientation are considered for testing. Experimental evidence shows that the DWT based segmentation provides significant improvement in recall rate and precision rate approximately 2.3% than DCT based segmentation with an increase in block classification time for both smooth and complex background images.

Environmentally Friendly Procedure Based on Supercritical Fluid Chromatography and Tandem Mass Spectrometry Molecular Networking for the Discovery of Potent Antiviral Compounds from Euphorbia semiperfoliata.

Science.gov (United States)

Nothias, Louis-Félix; Boutet-Mercey, Stéphanie; Cachet, Xavier; De La Torre, Erick; Laboureur, Laurent; Gallard, Jean-François; Retailleau, Pascal; Brunelle, Alain; Dorrestein, Pieter C; Costa, Jean; Bedoya, Luis M; Roussi, Fanny; Leyssen, Pieter; Alcami, José; Paolini, Julien; Litaudon, Marc; Touboul, David

2017-10-27

A supercritical fluid chromatography-based targeted purification procedure using tandem mass spectrometry and molecular networking was developed to analyze, annotate, and isolate secondary metabolites from complex plant extract mixture. This approach was applied for the targeted isolation of new antiviral diterpene esters from Euphorbia semiperfoliata whole plant extract. The analysis of bioactive fractions revealed that unknown diterpene esters, including jatrophane esters and phorbol esters, were present in the samples. The purification procedure using semipreparative supercritical fluid chromatography led to the isolation and identification of two new jatrophane esters (13 and 14) and one known (15) and three new 4-deoxyphorbol esters (16-18). The structure and absolute configuration of compound 16 were confirmed by X-ray crystallography. This compound was found to display antiviral activity against Chikungunya virus (EC 50 = 0.45 μM), while compound 15 proved to be a potent and selective inhibitor of HIV-1 replication in a recombinant virus assay (EC 50 = 13 nM). This study showed that a supercritical fluid chromatography-based protocol and molecular networking can facilitate and accelerate the discovery of bioactive small molecules by targeting molecules of interest, while minimizing the use of toxic solvents.

Synergy Maps: exploring compound combinations using network-based visualization.

Science.gov (United States)

Lewis, Richard; Guha, Rajarshi; Korcsmaros, Tamás; Bender, Andreas

2015-01-01

The phenomenon of super-additivity of biological response to compounds applied jointly, termed synergy, has the potential to provide many therapeutic benefits. Therefore, high throughput screening of compound combinations has recently received a great deal of attention. Large compound libraries and the feasibility of all-pairs screening can easily generate large, information-rich datasets. Previously, these datasets have been visualized using either a heat-map or a network approach-however these visualizations only partially represent the information encoded in the dataset. A new visualization technique for pairwise combination screening data, termed "Synergy Maps", is presented. In a Synergy Map, information about the synergistic interactions of compounds is integrated with information about their properties (chemical structure, physicochemical properties, bioactivity profiles) to produce a single visualization. As a result the relationships between compound and combination properties may be investigated simultaneously, and thus may afford insight into the synergy observed in the screen. An interactive web app implementation, available at http://richlewis42.github.io/synergy-maps, has been developed for public use, which may find use in navigating and filtering larger scale combination datasets. This tool is applied to a recent all-pairs dataset of anti-malarials, tested against Plasmodium falciparum, and a preliminary analysis is given as an example, illustrating the disproportionate synergism of histone deacetylase inhibitors previously described in literature, as well as suggesting new hypotheses for future investigation. Synergy Maps improve the state of the art in compound combination visualization, by simultaneously representing individual compound properties and their interactions. The web-based tool allows straightforward exploration of combination data, and easier identification of correlations between compound properties and interactions.

Determination of sulfur compounds in hydrotreated transformer base oil by potentiometric titration.

Science.gov (United States)

Chao, Qiu; Sheng, Han; Cheng, Xingguo; Ren, Tianhui

2005-06-01

A method was developed to analyze the distribution of sulfur compounds in model sulfur compounds by potentiometric titration, and applied to analyze hydrotreated transformer base oil. Model thioethers were oxidized to corresponding sulfoxides by tetrabutylammonium periodate and sodium metaperiodate, respectively, and the sulfoxides were titrated by perchloric acid titrant in acetic anhydride. The contents of aliphatic thioethers and total thioethers were then determined from that of sulfoxides in solution. The method was applied to determine the organic sulfur compounds in hydrotreated transformer base oil.

High-Tc Superconductors Based on FeAs Compounds

CERN Document Server

Izyumov, Yuri

2010-01-01

Physical properties and models of electronic structure are analyzed for a new class of high-TC superconductors which belong to iron-based layered compounds. Despite their variable chemical composition and differences in the crystal structure, these compounds possess similar physical characteristics, due to electron carriers in the FeAs layers and the interaction of these carriers with fluctuations of the magnetic order. A tremendous interest towards these materials is explained by the prospects of their practical use. In this monograph, a full picture of the formation of physical properties of these materials, in the context of existing theory models and electron structure studies, is given. The book is aimed at a broad circle of readers: physicists who study electronic properties of the FeAs compounds, chemists who synthesize them and specialists in the field of electronic structure calculations in solids. It is helpful not only to researchers active in the fields of superconductivity and magnetism, but also...

Elastic constants of the C15 laves phase compound NbCr2

International Nuclear Information System (INIS)

Chu, F.; He, Y.; Thoma, D.J.; Mitchell, T.E.

1995-01-01

Elastic properties of a solid are important because they relate to various fundamental solid-state phenomena such as interatomic potentials, equations of state, and phonon spectra. Elastic properties are also linked thermodynamically with specific heat, thermal expansion, Debye temperature, and Gruneisen parameter. Most important, knowledge of elastic constants is essential for many practical applications related to the mechanical properties of a solid as well: load-deflection, thermoelastic stress, internal strain (residual stress), sound velocities, dislocation core structure, and fracture toughness. In order to understand better the physical properties and deformation behavior of the C15 compound NbCr 2 , the authors have studied its elastic properties in this paper. In Section 2, the experimental methods are described, including the preparation of the sample and the measurement of the elastic constants. In Section 3, the experimental results are presented and the implications of these experimental results are discussed. Conclusions are drawn in Section 4

SEURAT-1 liver gold reference compounds: a mechanism-based review.

Science.gov (United States)

Jennings, Paul; Schwarz, Michael; Landesmann, Brigitte; Maggioni, Silvia; Goumenou, Marina; Bower, David; Leonard, Martin O; Wiseman, Jeffrey S

2014-12-01

There is an urgent need for the development of alternative methods to replace animal testing for the prediction of repeat dose chemical toxicity. To address this need, the European Commission and Cosmetics Europe have jointly funded a research program for 'Safety Evaluation Ultimately Replacing Animal Testing.' The goal of this program was the development of in vitro cellular systems and associated computational capabilities for the prediction of hepatic, cardiac, renal, neuronal, muscle, and skin toxicities. An essential component of this effort is the choice of appropriate reference compounds that can be used in the development and validation of assays. In this review, we focus on the selection of reference compounds for liver pathologies in the broad categories of cytotoxicity and lipid disorders. Mitochondrial impairment, oxidative stress, and apoptosis are considered under the category of cytotoxicity, while steatosis, cholestasis, and phospholipidosis are considered under the category of lipid dysregulation. We focused on four compound classes capable of initiating such events, i.e., chemically reactive compounds, compounds with specific cellular targets, compounds that modulate lipid regulatory networks, and compounds that disrupt the plasma membrane. We describe the molecular mechanisms of these compounds and the cellular response networks which they elicit. This information will be helpful to both improve our understanding of mode of action and help in the selection of appropriate mechanistic biomarkers, allowing us to progress the development of animal-free models with improved predictivity to the human situation.

Crystallographic and magnetic properties of (Nd,Dy)3Fe27.5(Ti,Mo)1.5 compounds

International Nuclear Information System (INIS)

Han, S.B.; Liu, X.F.; Lv, J.Y.; Peng, J.; Hao, Y.M.; Li, X.J.; Chen, D.F.; Xue, Y.J.; Li, J.H.; Hu, Z.B.

2006-01-01

A systematic study of the formation, structure and magnetic properties of (Nd,Dy) 3 Fe 27.5 (Ti,Mo) 1.5 compounds has been performed. Rietveld analyses of the X-ray patterns of the samples indicate that the concentrations of Ti and Mo affect the formation and structural properties slightly, whereas different rare-earth (Nd and Dy) contents influence them significantly. It is found that high Dy contents make it difficult to form the 3:29-type structures. The Curie temperatures of Nd 2.1 Dy 0.9 Fe 27.5 Ti 1.5- x Mo x decrease monotonically as more Ti was replaced by Mo but their saturation magnetizations remain almost unchanged; in contrast, for Nd 3- y Dy y Fe 27.5 TiMo 0.5 , their saturation magnetizations decrease monotonically with increasing Dy contents while their Curie temperatures are constant

Electrochemical properties of copper-based compounds with polyanion frameworks

Energy Technology Data Exchange (ETDEWEB)

Mizuno, Yoshifumi; Hata, Shoma; Suzuki, Kota; Hirayama, Masaaki; Kanno, Ryoji, E-mail: kanno@echem.titech.ac.jp

2016-03-15

The copper-based polyanion compounds Li{sub 6}CuB{sub 4}O{sub 10} and Li{sub 2}CuP{sub 2}O{sub 7} were synthesized using a conventional solid-state reaction, and their electrochemical properties were determined. Li{sub 6}CuB{sub 4}O{sub 10} showed reversible capacity of 340 mA g{sup −1} at the first discharge–charge process, while Li{sub 2}CuP{sub 2}O{sub 7} showed large irreversible capacity and thus low charge capacity. Ex situ X-ray diffraction (XRD) and X-ray absorption near edge structure (XANES) measurements revealed that the electrochemical Li{sup +} intercalation/deintercalation reaction in Li{sub 6}CuB{sub 4}O{sub 10} occurred via reversible Cu{sup 2+}/Cu{sup +} reduction/oxidation reaction. These differences in their discharge/charge mechanisms are discussed based on the strength of the Cu–O covalency via their inductive effects. - Graphical abstract: Electrochemical properties for Cu-based polyanion compounds were investigated. The electrochemical reaction mechanisms are strongly affected by their Cu–O covalentcy. - Highlights: • Electrochemical properties of Cu-based polyanion compounds were investigated. • The Li{sup +} intercalation/deintercalation reaction progressed in Li{sub 6}CuB{sub 4}O{sub 10}. • The electrochemical displacement reaction progressed in Li{sub 2}CuP{sub 2}O{sub 7}. • The strength of Cu–O covalency affects the reaction mechanism.

Targeting aquaporin function: potent inhibition of aquaglyceroporin-3 by a gold-based compound.

Directory of Open Access Journals (Sweden)

Ana Paula Martins

Full Text Available Aquaporins (AQPs are membrane channels that conduct water and small solutes such as glycerol and are involved in many physiological functions. Aquaporin-based modulator drugs are predicted to be of broad potential utility in the treatment of several diseases. Until today few AQP inhibitors have been described as suitable candidates for clinical development. Here we report on the potent inhibition of AQP3 channels by gold(III complexes screened on human red blood cells (hRBC and AQP3-transfected PC12 cells by a stopped-flow method. Among the various metal compounds tested, Auphen is the most active on AQP3 (IC(50 = 0.8±0.08 µM in hRBC. Interestingly, the compound poorly affects the water permeability of AQP1. The mechanism of gold inhibition is related to the ability of Au(III to interact with sulphydryls groups of proteins such as the thiolates of cysteine residues. Additional DFT and modeling studies on possible gold compound/AQP adducts provide a tentative description of the system at a molecular level. The mapping of the periplasmic surface of an homology model of human AQP3 evidenced the thiol group of Cys40 as a likely candidate for binding to gold(III complexes. Moreover, the investigation of non-covalent binding of Au complexes by docking approaches revealed their preferential binding to AQP3 with respect to AQP1. The high selectivity and low concentration dependent inhibitory effect of Auphen (in the nanomolar range together with its high water solubility makes the compound a suitable drug lead for future in vivo studies. These results may present novel metal-based scaffolds for AQP drug development.

Local structure and defect chemistry of [(SnSe)1.15]m(TaSe2) ferecrystals – A new type of layered intergrowth compound

International Nuclear Information System (INIS)

Grosse, Corinna; Atkins, Ryan; Kirmse, Holm; Mogilatenko, Anna; Neumann, Wolfgang; Johnson, David C.

2013-01-01

Highlights: •The crystal structure of [(SnSe) 1.15 ] m (TaSe 2 ) ferecrystals was analyzed by TEM. •The layers exhibit turbostratic disorder, but we also observed a local ordering. •The structures of the SnSe and TaSe 2 layers are similar to binary SnSe and 2H-TaSe 2 . •An increasing in-plane SnSe grain size with increasing m was observed. •Defect areas with missing, substituted or additional layers were found. -- Abstract: The atomic structure of the family of ferecrystals [(SnSe) 1.15 ] m (TaSe 2 ) (m = 1, 3, and 6) was investigated by means of transmission electron microscopy. The tantalum in the TaSe 2 layers was observed to have trigonal prismatic coordination similar to that found in the 2H polytype of bulk TaSe 2 . The structure of the SnSe constituent was found to be similar to that of orthorhombic α-SnSe. In the compounds with m = 1 and m = 3, regions with a local ordering of the layers along a commensurate axis, similar to the ordering in conventional misfit layer compounds, were observed. However, on a longer range the ferecrystals were found to exhibit a turbostratically disordered structure. Stacking defects were occasionally found in the samples in which a layer is interrupted and the surrounding layers are bent around these defects, while maintaining abrupt interfaces instead of interdiffusing. Volume defects were found in one sample of [(SnSe) 1.15 ] 1 (TaSe 2 ) 1 in which a SnSe layer locally substitutes a part of a TaSe 2 layer without interrupting the surrounding layers

Accelerating Multiple Compound Comparison Using LINGO-Based Load-Balancing Strategies on Multi-GPUs.

Science.gov (United States)

Lin, Chun-Yuan; Wang, Chung-Hung; Hung, Che-Lun; Lin, Yu-Shiang

2015-01-01

Compound comparison is an important task for the computational chemistry. By the comparison results, potential inhibitors can be found and then used for the pharmacy experiments. The time complexity of a pairwise compound comparison is O(n (2)), where n is the maximal length of compounds. In general, the length of compounds is tens to hundreds, and the computation time is small. However, more and more compounds have been synthesized and extracted now, even more than tens of millions. Therefore, it still will be time-consuming when comparing with a large amount of compounds (seen as a multiple compound comparison problem, abbreviated to MCC). The intrinsic time complexity of MCC problem is O(k (2) n (2)) with k compounds of maximal length n. In this paper, we propose a GPU-based algorithm for MCC problem, called CUDA-MCC, on single- and multi-GPUs. Four LINGO-based load-balancing strategies are considered in CUDA-MCC in order to accelerate the computation speed among thread blocks on GPUs. CUDA-MCC was implemented by C+OpenMP+CUDA. CUDA-MCC achieved 45 times and 391 times faster than its CPU version on a single NVIDIA Tesla K20m GPU card and a dual-NVIDIA Tesla K20m GPU card, respectively, under the experimental results.

Phosphorus-based compounds for EUV multilayer optics materials

NARCIS (Netherlands)

Medvedev, Viacheslav; Yakshin, Andrey; van de Kruijs, Robbert Wilhelmus Elisabeth; Bijkerk, Frederik

2015-01-01

We have evaluated the prospects of phosphorus-based compounds in extreme ultraviolet multilayer optics. Boron phosphide (BP) is suggested to be used as a spacer material in reflective multilayer optics operating just above the L-photoabsorption edge of P (λ ≈9.2 nm). Mo, Ag, Ru, Rh, and Pd were

A Mobile-Based High Sensitivity On-Field Organophosphorus Compounds Detecting System for IoT-Based Food Safety Tracking

Directory of Open Access Journals (Sweden)

Han Jin

2017-01-01

Full Text Available A mobile-based high sensitivity absorptiometer is presented to detect organophosphorus (OP compounds for Internet-of-Things based food safety tracking. This instrument consists of a customized sensor front-end chip, LED-based light source, low power wireless link, and coin battery, along with a sample holder packaged in a recycled format. The sensor front-end integrates optical sensor, capacitive transimpedance amplifier, and a folded-reference pulse width modulator in a single chip fabricated in a 0.18 μm 1-poly 5-metal CMOS process and has input optical power dynamic range of 71 dB, sensitivity of 3.6 nW/cm2 (0.77 pA, and power consumption of 14.5 μW. Enabled by this high sensitivity sensor front-end chip, the proposed absorptiometer has a small size of 96 cm3, with features including on-field detection and wireless communication with a mobile. OP compound detection experiments of the handheld system demonstrate a limit of detection (LOD of 0.4 μmol/L, comparable to that of a commercial spectrophotometer. Meanwhile, an android-based application (APP is presented which makes the absorptiometer access to the Internet-of-Things (IoT.

Antiproliferative compounds of Cyphostemma greveana from a Madagascar dry forest.

Science.gov (United States)

Cao, Shugeng; Hou, Yanpeng; Brodie, Peggy; Miller, James S; Randrianaivo, Richard; Rakotobe, Etienne; Rasamison, Vincent E; Kingston, David G I

2011-04-01

Bioassay-guided fractionation of the EtOH extracts obtained from a plant identified as Cyphostemma greveana Desc. (Vitaceae) led to the identification of one macrolide, lasiodiplodin (1), three sesquiterpenoids, 12-hydroxy-15-oxoselina-4,11-diene (2), 1β,6α-dihydroxyeudesm-4(15)-ene (3), and (7R*)-opposit-4(15)-ene-1β,7-diol (5), and a new diterpenoid, 16,18-dihydroxykolavenic acid lactone (4). All the isolates were tested against the A2780 human ovarian cancer cell line, and compound 4 and a fraction containing 5 as the major constituent showed antiproliferative activities with IC(50) values of 0.44 μM (0.14 μg/ml) and 0.045 μg/ml, respectively. A partial synthesis of compound 5 was carried out, but the pure synthetic compound was inactive, indicating that the activity of the fraction containing it must be due to a very minor and as yet unidentified substance. Copyright © 2011 Verlag Helvetica Chimica Acta AG, Zürich.

Synthesis and characterization of Fe-Ti-Sb intermetallic compounds: Discovery of a new Slater-Pauling phase

Science.gov (United States)

Naghibolashrafi, N.; Keshavarz, S.; Hegde, Vinay I.; Gupta, A.; Butler, W. H.; Romero, J.; Munira, K.; LeClair, P.; Mazumdar, D.; Ma, J.; Ghosh, A. W.; Wolverton, C.

2016-03-01

Compounds of Fe, Ti, and Sb were prepared using arc melting and vacuum annealing. Fe2TiSb , expected to be a full Heusler compound crystallizing in the L 21 structure, was shown by XRD and SEM analyses to be composed of weakly magnetic grains of nominal composition Fe1.5TiSb with iron-rich precipitates in the grain boundaries. FeTiSb, a composition consistent with the formation of a half-Heusler compound, also decomposed into Fe1.5TiSb grains with Ti-Sb rich precipitates and was weakly magnetic. The dominant Fe1.5TiSb phase appears to crystallize in a defective L 21 -like structure with iron vacancies. Based on this finding, a first-principles DFT-based binary cluster expansion of Fe and vacancies on the Fe sublattice of the L 21 structure was performed. Using the cluster expansion, we computationally scanned >103 configurations and predict a novel, stable, nonmagnetic semiconductor phase to be the zero-temperature ground state. This new structure is an ordered arrangement of Fe and vacancies, belonging to the space group R 3 m , with composition Fe1.5TiSb , i.e., between the full- and half-Heusler compositions. This phase can be visualized as alternate layers of L 21 phase Fe2TiSb and C 1b phase FeTiSb, with layering along the [111] direction of the original cubic phases. Our experimental results on annealed samples support this predicted ground-state composition, but further work is required to confirm that the R 3 m structure is the ground state.

The crystal structure of the mixed-layer Aurivillius phase Bi 5Ti 1.5W 1.5O 15

Science.gov (United States)

Tellier, J.; Boullay, Ph.; Créon, N.; Mercurio, D.

2005-09-01

The crystal structure of the 1+2 mixed-layer Aurivillius phase Bi 5Ti 1.5W 1.5O 15 (SG I2cm n o 46: -cba, Z=4, a=5.4092(3) Å, b=5.3843(3) Å and c=41.529(3) Å) consisting of the ordered intergrowth of one and two octahedra thick perovskite-type blocks separated by [Bi 2O 2] 2+ slabs is reported. Supported by an electron diffraction investigation and, using the Rietveld analysis, it is shown that this compound should be described using a I-centering lattice in agreement with the generalised structural model of the Aurivillius type compounds recently presented by the authors. The structure of this Bi 5Ti 1.5W 1.5O 15 phase is analyzed in comparison with the related simple members (Bi 2WO 6 and Bi 3Ti 1.5W 0.5O 9). The crystal structure of Bi 3Ti 1.5W 0.5O 9 is also reported.

Accelerating Multiple Compound Comparison Using LINGO-Based Load-Balancing Strategies on Multi-GPUs

Directory of Open Access Journals (Sweden)

Chun-Yuan Lin

2015-01-01

Full Text Available Compound comparison is an important task for the computational chemistry. By the comparison results, potential inhibitors can be found and then used for the pharmacy experiments. The time complexity of a pairwise compound comparison is O(n2, where n is the maximal length of compounds. In general, the length of compounds is tens to hundreds, and the computation time is small. However, more and more compounds have been synthesized and extracted now, even more than tens of millions. Therefore, it still will be time-consuming when comparing with a large amount of compounds (seen as a multiple compound comparison problem, abbreviated to MCC. The intrinsic time complexity of MCC problem is O(k2n2 with k compounds of maximal length n. In this paper, we propose a GPU-based algorithm for MCC problem, called CUDA-MCC, on single- and multi-GPUs. Four LINGO-based load-balancing strategies are considered in CUDA-MCC in order to accelerate the computation speed among thread blocks on GPUs. CUDA-MCC was implemented by C+OpenMP+CUDA. CUDA-MCC achieved 45 times and 391 times faster than its CPU version on a single NVIDIA Tesla K20m GPU card and a dual-NVIDIA Tesla K20m GPU card, respectively, under the experimental results.

RE{sub 2}B{sub 8}O{sub 15} (RE = La, Pr, Nd). Syntheses of three new rare earth borates isotypic to Ce{sub 2}B{sub 8}O{sub 15}

Energy Technology Data Exchange (ETDEWEB)

Glaetzle, Matthias; Hoerder, Gregor J.; Huppertz, Hubert [Innsbruck Univ. (Austria). Inst. fuer Allgemeine, Anorganische und Theoretische Chemie

2016-08-01

The rare earth borates RE{sub 2}B{sub 8}O{sub 15} (RE = La, Pr, Nd) were synthesized in a Walker-type multianvil apparatus under conditions of 5.5 GPa and 1100 C. Starting from the corresponding rare earth oxides and boron oxide, the syntheses yielded crystalline products of all new compounds that allowed crystal structure analyses based on single-crystal X-ray diffraction data for La{sub 2}B{sub 8}O{sub 15} and Nd{sub 2}B{sub 8}O{sub 15}. The compound Pr{sub 2}B{sub 8}O{sub 15} could be characterized via X-ray powder diffractometry. The results show that the new compounds crystallize isotypically to Ce{sub 2}B{sub 8}O{sub 15} in the monoclinic space group P2/c. The infrared spectra of RE{sub 2}B{sub 8}O{sub 15} (RE = La, Pr, Nd) have also been studied.

Antiproliferative Compounds of Cyphostemma greveana from a Madagascar Dry Forest[1

Science.gov (United States)

Cao, Shugeng; Hou, Yanpeng; Brodie, Peggy; Miller, James S.; Randrianaivo, Richard; Rakotobe, Etienne; Rasamison, Vincent E.

2011-01-01

Bioassay-guided fractionation of the EtOH extracts obtained from a plant identified as Cyphostemma greveana Desc. (Vitaceae) led to the identification of one macrolide, lasiodiplodin (1), three sesquiterpenoids, 12-hydroxy-15-oxo-selina-4,1l-diene (2), 1β,6α-dihydroxyeudesm-4(15)-ene (3), and (7R*)-opposit-4(15)-ene-1β,7-diol (5), and the new diterpenoid, 16,18-dihydroxykolavenic acid lactone (4). All the isolates were tested against the A2780 human ovarian cancer cell line, and compound 4 and a fraction containing 5 as the major constituent showed antiproliferative activities with IC50 values of 0.44 μM (0.14 μg/mL) and 0.045 μg/mL, respectively. A semisynthesis of compound 5 was carried out, but the pure synthetic compound was inactive, indicating that the activity of the fraction containing it must be due to a very minor and as yet unidentified substance. PMID:21480509

A new feedback image encryption scheme based on perturbation with dynamical compound chaotic sequence cipher generator

Science.gov (United States)

Tong, Xiaojun; Cui, Minggen; Wang, Zhu

2009-07-01

The design of the new compound two-dimensional chaotic function is presented by exploiting two one-dimensional chaotic functions which switch randomly, and the design is used as a chaotic sequence generator which is proved by Devaney's definition proof of chaos. The properties of compound chaotic functions are also proved rigorously. In order to improve the robustness against difference cryptanalysis and produce avalanche effect, a new feedback image encryption scheme is proposed using the new compound chaos by selecting one of the two one-dimensional chaotic functions randomly and a new image pixels method of permutation and substitution is designed in detail by array row and column random controlling based on the compound chaos. The results from entropy analysis, difference analysis, statistical analysis, sequence randomness analysis, cipher sensitivity analysis depending on key and plaintext have proven that the compound chaotic sequence cipher can resist cryptanalytic, statistical and brute-force attacks, and especially it accelerates encryption speed, and achieves higher level of security. By the dynamical compound chaos and perturbation technology, the paper solves the problem of computer low precision of one-dimensional chaotic function.

Fused heterocyclic compounds bearing bridgehead nitrogen as potent HIV-1 NNRTIs. Part 1: design, synthesis and biological evaluation of novel 5,7-disubstituted pyrazolo[1,5-a]pyrimidine derivatives.

Science.gov (United States)

Tian, Ye; Du, Deping; Rai, Diwakar; Wang, Liu; Liu, Huiqing; Zhan, Peng; De Clercq, Erik; Pannecouque, Christophe; Liu, Xinyong

2014-04-01

In our continuous efforts to identify novel potent HIV-1 NNRTIs, a novel class of 5,7-disubstituted pyrazolo[1,5-a]pyrimidine derivatives were rationally designed, synthesized and evaluated for their anti-HIV activities in MT4 cell cultures. Biological results showed that most of the tested compounds displayed excellent activity against wild-type HIV-1 with a wide range of EC50 values from 5.98 to 0.07μM. Among the active compounds, 5a was found to be the most promising analogue with an EC50 of 0.07μM against wild-type HIV-1 and very high selectivity index (SI, 3999). Compound 5a was more effective than the reference drugs nevirapine (by 2-fold) and delavirdine (by 2-fold). In order to further confirm their binding target, an HIV-1 RT inhibitory assay was also performed. Furthermore, SAR analysis among the newly synthesized compounds was discussed and the binding mode of the active compound 5a was rationalized by molecular modeling studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Study of the relationship between chemical structure and antimicrobial activity in a series of hydrazine-based coordination compounds.

Science.gov (United States)

Dobrova, B N; Dimoglo, A S; Chumakov, Y M

2000-08-01

The dependence of antimicrobial activity on the structure of compounds is studied in a series of compounds based on hydrazine coordinated with ions of Cu(II), Ni(II) and Pd(II). The study has been carried out by means of the original electron-topological method developed earlier. A molecular fragment has been found that is only characteristic of biologically active compounds. Its spatial and electron parameters have been used for the quantitative assessment of the activity in view. The results obtained can be used for the antimicrobial activity prediction in a series of compounds with similar structures.

Reactivity-based industrial volatile organic compounds emission inventory and its implications for ozone control strategies in China

Science.gov (United States)

Liang, Xiaoming; Chen, Xiaofang; Zhang, Jiani; Shi, Tianli; Sun, Xibo; Fan, Liya; Wang, Liming; Ye, Daiqi

2017-08-01

Increasingly serious ozone (O3) pollution, along with decreasing NOx emission, is creating a big challenge in the control of volatile organic compounds (VOCs) in China. More efficient and effective measures are assuredly needed for controlling VOCs. In this study, a reactivity-based industrial VOCs emission inventory was established in China based on the concept of ozone formation potential (OFP). Key VOCs species, major VOCs sources, and dominant regions with high reactivity were identified. Our results show that the top 15 OFP-based species, including m/p-xylene, toluene, propene, o-xylene, and ethyl benzene, contribute 69% of the total OFP but only 30% of the total emission. The architectural decoration industry, oil refinery industry, storage and transport, and seven other sources constituted the top 10 OFP subsectors, together contributing a total of 85%. The provincial and spatial characteristics of OFP are generally consistent with those of mass-based inventory. The implications for O3 control strategies in China are discussed. We propose a reactivity-based national definition of VOCs and low-reactive substitution strategies, combined with evaluations of health risks. Priority should be given to the top 15 or more species with high reactivity through their major emission sources. Reactivity-based policies should be flexibly applied for O3 mitigation based on the sensitivity of O3 formation conditions.

A Concentrator Photovoltaic System Based on a Combination of Prism-Compound Parabolic Concentrators

Directory of Open Access Journals (Sweden)

Ngoc Hai Vu

2016-08-01

Full Text Available We present a cost-effective concentrating photovoltaic system composed of a prism and a compound parabolic concentrator (P-CPC. In this approach, the primary collector consists of a prism, a solid compound parabolic concentrator (CPC, and a slab waveguide. The prism, which is placed on the input aperture of CPC, directs the incoming sunlight beam to be parallel with the main axes of parabolic rims of CPC. Then, the sunlight is reflected at the parabolic rims and concentrated at the focal point of these parabolas. A slab waveguide is coupled at the output aperture of the CPC to collect focused sunlight beams and to guide them to the solar cell. The optical system was modeled and simulated with commercial ray tracing software (LightTools™. Simulation results show that the optical efficiency of a P-CPC can achieve up to 89%. when the concentration ratio of the P-CPC is fixed at 50. We also determine an optimal geometric structure of P-CPC based on simulation. Because of the simplicity of the P-CPC structure, a lower-cost mass production process is possible. A simulation based on optimal structure of P-CPC was performed and the results also shown that P-CPC has high angular tolerance for input sunlight. The high tolerance of the input angle of sunlight allows P-CPC solar concentrator utilize a single sun tracking system instead of a highly precise dual suntracking system as cost effective solution.

Orientation distribution in Bi2Te3-based compound prepared by spark plasma sintering

International Nuclear Information System (INIS)

Kim, K.T.; Kim, Y.H.; Lim, C.H.; Cho, D.C.; Lee, Y.S.; Lee, C.H.

2005-01-01

P-type Bi 0.5 Sb 1.5 Te 3 compounds doped with 3wt.% Te were fabricated by spark plasma sintering after mixing large powders(P L ) and small powders(P S ). We could obtained the highest figure of merit(Z C ) of 2.89 x 10 -3 /K in sintered compound mixed to P L :P S =80:20. This resulted from the increase of orientation by large powders(P S ) and the reduce of pores by small powders. The figure of merit(Z C ) of the sintered compound using only small powders(P S ) showed lower value of 2.67 x 10 -3 /K compared with that of sintered compound mixed to P L :P S =80:20 due to the increase of electrical resistivity. (orig.)

Microstructural and thermoelectric properties of p-type Te-doped Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} and n-type SbI{sub 3}-doped Bi{sub 2}Te{sub 2.85}Se{sub 0.15} compounds

Energy Technology Data Exchange (ETDEWEB)

Seo, J; Park, K; Lee, C; Kim, J

1997-07-01

The p-type Te-doped Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} and n-type SbI{sub 3}-doped Bi{sub 2}Te{sub 2.85}Se{sub 0.15} thermoelectric compounds were fabricated by hot pressing in the temperature range of 380 to 440 C under 200 MPa in Ar. Both the compounds were highly dense and showed high crystalline quality. The grains of the compounds were preferentially oriented and contained many dislocations through the hot pressing. The fracture path followed the transgranular cleavage planes, which are perpendicular to the c-axis. In addition, with increasing the pressing temperature, the figure of merit was increased. The highest values of figure of merit for the p- and n-type compounds, which were obtained at 420 C, were 2.69 x 10{sup {minus}3}/K and 2.35 x 10{sup {minus}3}/K, respectively.

Synthesis and optoelectronic characterization of some triphenylamine-based compounds containing strong acceptor substituents

Energy Technology Data Exchange (ETDEWEB)

Grigoras, Mircea, E-mail: grim@icmpp.ro; Ivan, Teofilia; Vacareanu, Loredana; Catargiu, Ana Maria; Tigoianu, Radu

2014-09-15

Three novel triphenylamine-based compounds containing strong electron acceptor groups have been synthesized and their comparative photophysical properties are presented. These compounds were obtained by a two-step method: (i) triphenylamine compounds with one, two and three phenylacetylene arms were synthesized by Sonogashira reaction between iodine-substituted triphenylamines and phenylacetylene, followed by (ii) post-modification of these electron-rich alkynes by addition of the strong electron acceptor, tetracyanoethylene. Characterization of all oligomers was made by FTIR, {sup 1}H-NMR, UV–vis and fluorescence spectroscopy. A batochromic shifting of the UV and photoluminescence maxima was observed with the increase of the acceptor group number. The electrochemical behavior was studied by cyclic voltammetry. The cyclic voltammograms have evidenced that triphenylamine-phenylacetylene compounds undergo only oxidation processes while compounds modified with tetracyanoethylene show both oxidation and reduction peaks associated with donor and acceptor groups, respectively. The donor–acceptor compounds coordinate metal ions (i.e., Hg{sup 2+} and Sn{sup 2+}) by cyano groups resulting in the decreasing of charge transfer band intensity, and they can be used as chemosensors. - Highlights: • Three triphenylamine-based ethynylene compounds were prepared by Sonogashira reaction. • Post-modification of ethynylene linkages by tetracyanethylene cycloaddition and retroconversion led to donor–acceptor compounds. • Photophysical properties of donor–acceptor oligomers were studied in different solvents.

Synthesis and anticonvulsant activity of certain chalcone based pyrazoline compounds

Directory of Open Access Journals (Sweden)

Sudhakara Rao Gerapati

2015-09-01

Full Text Available Convulsions are involuntary, violent, spasmodic and prolonged contractions of skeletal muscles. That means a patient may have epilepsy without convulsions and vice versa. Epilepsy is a common neurological abnormality affecting about 1% of the world population. The primary objectives of these synthesized compounds are to suppress seizures and provide neuroprotection by minimizing the effects from seizure attacks. Here some of the chalcones and chalcone based various pyrazolines were evaluated for anticonvulsant activity. Their structures have been elucidated on the basis of elemental analyses and spectroscopic studies (IR, 1H-NMR & Mass spectroscopy. A preliminary evaluation of the prepared compounds has indicated that some of them exhibit moderate to significant anticonvulsant activity compared to a diazepam standard1-3.  All compounds were tested for their anticonvulsant activity using maximal electroshock induced convulsions (MES in mice at a dose level of 4 mg/kg.b.w. The compounds  Ph1, Ph2 , Py2 ,Py3 and Py4 have shown  to  good anticonvulsant activity when doses are administered as 25mg/ kg.b.w  , reduced the phases of seizures severity and  found to be active and also  increased survival rate. Remaining compounds are less efficacious.

Immobilization of N-Heterocyclic Carbene Compounds: A Synthetic Perspective.

Science.gov (United States)

Zhong, Rui; Lindhorst, Anja C; Groche, Florian J; Kühn, Fritz E

2017-02-08

Over the course of the past 15 years the success story of N-heterocyclic carbene (NHC) compounds in organic, inorganic, and organometallic chemistry has been extended to another dimension. The immobilization of NHC compounds, undergoing continuous diversification, broadens their range of applications and leads to new solutions for challenges in catalytic and synthetic chemistry. This review intends to present a synthetic toolkit for the immobilization of NHC compounds, giving the reader an overview on synthetic techniques and strategies available in the literature. By individually summarizing and assessing the synthetic steps of the immobilization process, a comprehensive picture of the strategies and methodologies for the immobilization of NHC compounds is presented. Furthermore, the characterization of supported NHC compounds is discussed in detail in order to set up necessary criteria for an in-depth analysis of the immobilized derivatives. Finally, the catalytic applications of immobilized NHC compounds are briefly reviewed to illustrate the practical use of this technique for a broad variety of reaction types.

Development of New Cryocooler Regenerator Materials-Ductile Intermetallic Compounds

International Nuclear Information System (INIS)

Gschneidner, K.A.; Pecharsky, A.O.; Pecharsky, V.K.

2004-01-01

The volumetric heat capacities of a number of binary and ternary Er- and Tm-based intermetallic compounds, which exhibited substantial ductilities, were measured from ∼3 to ∼350 K. They have the RM stoichiometry (where R = Er or Tm, and M is a main group or transition metal) and crystallize in the CsCl-type structure. The heat capacities of the Tm-based compounds are in general larger than the corresponding Er-based materials. Many of them have heat capacities which are significantly larger than those of the low temperature ( 2 , Er 3 Ni and ErNi. Utilization of the new materials as regenerators in the various cryocoolers should improve the performance of these refrigeration units for cooling below 15 K

A system for oxygen-15 labeled blood for medical applications

International Nuclear Information System (INIS)

Subramanyam, R.; Bucelewicz, W.M.; Hoop, B. Jr.; Jones, S.C.

1977-01-01

Oxygen-15 labeled compounds in blood have been used successfully for cerebral circulation and cerebral oxygen metabolism measurements. The present paper describes a system for the rapid sequential production of 15 O-HgB, C 15 O-Hgb and H 2 15 O in blood under sterile and pyrogen-free conditions. A tonometer has been adopted for labeling blood without hemolysis and foam production. (author)

A role for fragment-based drug design in developing novel lead compounds for central nervous system targets

Directory of Open Access Journals (Sweden)

Michael J. Wasko

2015-09-01

Full Text Available Hundreds of millions of U.S. dollars are invested in the research and development of a single drug. Lead compound development is an area ripe for new design strategies. Therapeutic lead candidates have been traditionally found using high-throughput in vitro pharmacologic screening, a costly method for assaying thousands of compounds. This approach has recently been augmented by virtual screening, which employs computer models of the target protein to narrow the search for possible leads. A variant of virtual screening is fragment-based drug design, an emerging in silico lead discovery method that introduces low molecular weight fragments, rather than intact compounds, into the binding pocket of the receptor model. These fragments serve as starting points for growing the lead candidate. Current efforts in virtual fragment-based drug design within central nervous system (CNS targets are reviewed, as is a recent rule-based optimization strategy in which new molecules are generated within a 3D receptor binding pocket using the fragment as a scaffold. This process places special emphasis on creating synthesizable molecules but also exposes computational questions worth addressing. Fragment-based methods provide a viable, relatively low-cost alternative for therapeutic lead discovery and optimization that can be applied to CNS targets to augment current design strategies.

Inclusion Compound Based Approach to Forming Arrays of Artificial Dipolar Molecular Rotors: A Search for Optimal Rotor Structures

Czech Academy of Sciences Publication Activity Database

Kobr, L.; Zhao, K.; Shen, X.; Shoemaker, R. K.; Rogers, C. T.; Michl, Josef

2013-01-01

Roč. 25, č. 3 (2013), s. 443-448 ISSN 0935-9648 EU Projects: European Commission(XE) 227756 - DIPOLAR ROTOR ARRAY Grant - others:NSF(US) CHE 0848663 Institutional support: RVO:61388963 Keywords : inclusion compounds * molecular rotors * ferroelectricity * two-dimensional arrays Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 15.409, year: 2013

Stable isotopes labelled compounds

International Nuclear Information System (INIS)

1982-09-01

The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme

Sublimation thermodynamics of four fluoroquinolone antimicrobial compounds

International Nuclear Information System (INIS)

Blokhina, Svetlana; Sharapova, Angelica; Ol’khovich, Marina; Perlovich, German

2017-01-01

Highlights: • The vapor pressures of ciprofloxacin, enrofloxacin, norfloxacin and levofloxacin were measured. • The values of enthalpies, entropies and Gibbs energies of sublimation were calculated at T = 298.15 K. • Thermophysical characteristics of the studied compounds were determined. • The influence hydrogen bonds in crystal lattices on the sublimation enthalpy was discussed. - Abstract: The transpiration method was used to measure the vapor pressures as a function of temperature of the following antimicrobial drugs: ciprofloxacin, enrofloxacin, norfloxacin and levofloxacin. Based on these results standard molar enthalpies, entropies and Gibbs energies of sublimation at T = 298.15 K were calculated and a correlation between the crystal lattice energy and the saturation vapor pressure in a number of fluoroquinolones was found. The thermophysical characteristics of the compounds studied were determined by DSC. The influence of different structural fragments of molecules substituents and the effects of hydrogen bonds in crystal lattices on the sublimation enthalpy was discussed.

EuroFIR-BASIS - a combined composition and biological activity database for bioactive compounds in plant-based foods

DEFF Research Database (Denmark)

Gry, Jørn; Black, Lucinda; Eriksen, Folmer Damsted

2007-01-01

Mounting evidence suggests that certain non-nutrient bioactive compounds promote optimal human health and reduce the risk of chronic disease. An Internet-deployed database, EuroFIR-BASIS, which uniquely combines food composition and biological effects data for plant-based bioactive compounds......, is being developed. The database covers multiple compound classes and 330 major food plants and their edible parts with data sourced from quality-assessed, peer-reviewed literature. The database will be a valuable resource for food regulatory and advisory bodies, risk authorities, epidemiologists...... and researchers interested in diet and health relationships, and product developers within the food industry....

Chemical compound-based direct reprogramming for future clinical applications

Science.gov (United States)

Takeda, Yukimasa; Harada, Yoshinori; Yoshikawa, Toshikazu; Dai, Ping

2018-01-01

Recent studies have revealed that a combination of chemical compounds enables direct reprogramming from one somatic cell type into another without the use of transgenes by regulating cellular signaling pathways and epigenetic modifications. The generation of induced pluripotent stem (iPS) cells generally requires virus vector-mediated expression of multiple transcription factors, which might disrupt genomic integrity and proper cell functions. The direct reprogramming is a promising alternative to rapidly prepare different cell types by bypassing the pluripotent state. Because the strategy also depends on forced expression of exogenous lineage-specific transcription factors, the direct reprogramming in a chemical compound-based manner is an ideal approach to further reduce the risk for tumorigenesis. So far, a number of reported research efforts have revealed that combinations of chemical compounds and cell-type specific medium transdifferentiate somatic cells into desired cell types including neuronal cells, glial cells, neural stem cells, brown adipocytes, cardiomyocytes, somatic progenitor cells, and pluripotent stem cells. These desired cells rapidly converted from patient-derived autologous fibroblasts can be applied for their own transplantation therapy to avoid immune rejection. However, complete chemical compound-induced conversions remain challenging particularly in adult human-derived fibroblasts compared with mouse embryonic fibroblasts (MEFs). This review summarizes up-to-date progress in each specific cell type and discusses prospects for future clinical application toward cell transplantation therapy. PMID:29739872

Pyrolysis mechanism of microalgae Nannochloropsis sp. based on model compounds and their interaction

International Nuclear Information System (INIS)

Wang, Xin; Tang, Xiaohan; Yang, Xiaoyi

2017-01-01

Highlights: • Pyrolysis experiments were conducted by model compounds of algal components. • Interaction affected little bio-crude yield of model compounds co-pyrolysis. • Some interaction pathways between microalgae components were recommended. • N-heterocyclic compounds were further pyrolysis products of Maillard reaction products. • Surfactant synthesis (lipid-amino acids and lipid-glucose) between algal components. - Abstract: Pyrolysis is one of important pathways to convert microalgae to liquid biofuels and key components of microalgae have different chemical composition and structure, which provides a barrier for large-scale microalgae-based liquid biofuel application. Microalgae component pyrolysis mechanism should be researched to optimal pyrolysis process parameters. In this study, single pyrolysis and co-pyrolysis of microalgal components (model compounds castor oil, soybean protein and glucose) were conducted to reveal interaction between them by thermogrametric analysis and bio-crude evaluation. Castor oil (model compound of lipid) has higher pyrolysis temperature than other model compounds and has the maximum contribution to bio-crude formation. Bio-crude from soybean protein has higher N-heterocyclic compounds as well as phenols, which could be important aromatic hydrocarbon source during biorefineries and alternative aviation biofuel production. Potential interaction pathways based on model compounds are recommended including further decomposition of Maillard reaction products (MRPs) and surfactant synthesis, which indicate that glucose played an important role on pyrolysis of microalgal protein and lipid components. The results should provide necessary information for microalgae pyrolysis process optimization and large-scale pyrolysis reactor design.

Crown-ether functionalized carbon nanotubes for purification of lithium compounds: computational and experimental study

International Nuclear Information System (INIS)

Singha Deb, A.K.; Arora, S.K.; Joshi, J.M.; Ali, Sk. M.; Shenoy, K.T.; Goyal, Aiana

2015-01-01

Lithium compounds finds several applications in nuclear science and technology, viz, lithium fluoride/hydroxide/alloys are used as dosimetric materials in luminescence devices, molten-salt breeder reactor, international thermonuclear experimental reactor, single crystal based neutron detectors etc. The lithium compounds should be in a proper state of purity; especially it should not contain other alkali metal cations which can downgrade the performance. Hence, there is a need to develop a process for purification of the lithium salt to achieve the desired quality. Therefore an attempt has been made to develop advanced nanomaterials for purification of the lithium salts. In this work, benzo-15-crown-5(B15C5) functionalized carbon nanotubes (CNTs), owing to the good adsorption properties of CNT and alkali metal encapsulation behaviour of B15C5, were showed to bind preferentially with sodium and potassium ions compared to lithium ions. DFT based computation calculations have shown that the free energy of complexation of Na + and K + by B15C5-CNT is higher than that of Li + , implying that B15C5-CNT selectively binds Na + and K + . The experimental batch solid-liquid extraction has also revealed the same trend as in the calculations. The crown-ethers functionalized CNTs have the potentiality for use in purifying lithium compounds. (author)

Methylene-Cycloalkylacetate (MCA) Scaffold-Based Compounds as Novel Neurotropic Agents.

Science.gov (United States)

Lankri, David; Haham, Dikla; Lahiani, Adi; Lazarovici, Philip; Tsvelikhovsky, Dmitry

2018-04-18

One of the main symptoms in degenerative diseases is death of neuronal cell followed by the loss of neuronal pathways. In neuronal cultures, neurite outgrowths are cell sprouts capable of transforming into either axons or dendrites, to further form functional neuronal synaptic connections. Such connections have an important role in brain cognition, neuronal plasticity, neuronal survival, and regeneration. Therefore, drugs that stimulate neurite outgrowth may be found beneficial in ameliorating neural degeneration. Here, we establish the existence of a unique family of methylene-cycloalkylacetate-based molecules (MCAs) that interface with neuronal cell properties and operate as acceptable pharmacophores for a novel neurotropic (neurite outgrowth inducing) lead compounds. Using an established PC12 cell bioassay, we investigated the neurotropic effect of methylene-cycloalkylacetate compounds by comparison to NGF, a known neurotropic factor. Micrographs of the cells were collected by using a light microscope camera, and digitized photographs were analyzed for compound-induced neurotropic activity using an NIH image protocol. The results indicate that the alkene element, integrated within the cycloalkylacetate core, is indispensable for neurotropic activity. The discovered lead compounds need further mechanistic investigation and may be improved toward development of a neurotropic drug.

Prediction of Positions of Active Compounds Makes It Possible To Increase Activity in Fragment-Based Drug Development

Directory of Open Access Journals (Sweden)

Yoshifumi Fukunishi

2011-05-01

Full Text Available We have developed a computational method that predicts the positions of active compounds, making it possible to increase activity as a fragment evolution strategy. We refer to the positions of these compounds as the active position. When an active fragment compound is found, the following lead generation process is performed, primarily to increase activity. In the current method, to predict the location of the active position, hydrogen atoms are replaced by small side chains, generating virtual compounds. These virtual compounds are docked to a target protein, and the docking scores (affinities are examined. The hydrogen atom that gives the virtual compound with good affinity should correspond to the active position and it should be replaced to generate a lead compound. This method was found to work well, with the prediction of the active position being 2 times more efficient than random synthesis. In the current study, 15 examples of lead generation were examined. The probability of finding active positions among all hydrogen atoms was 26%, and the current method accurately predicted 60% of the active positions.

Investigations on Ce- and Yb-based intermetallic compounds

International Nuclear Information System (INIS)

Elenbaas, R.A.

1980-01-01

The author describes investigations on a number of cerium- and ytterbium-based intermetallic compounds and alloys, yielding a lot of experimental results which could not always be put in a quantitative picture. All experimental data are consistent with a single-ion behaviour, where the 4f state is more or less modified by the conduction electrons. In the investigated systems several different features of the magnetism of cerium atoms in metals were studied. (Auth.)

The discovery of bioisoster compound for plumbagin using the knowledge-based rational method

Science.gov (United States)

Jeong, Seo Hee; Choi, Jung Sup; Ko, Young Kwan; Kang, Nam Sook

2015-04-01

Arabidopsis thaliana 7-Keto-8-AminoPelargonic Acid Synthase (AtKAPAS) is a crucial herbicide target, and AtKAPAS inhibitors are widely available in the agrochemical market. The herbicide plumbagin is known as a potent inhibitor for AtKAPAS but it is extremely toxic. In this study, we identified the metabolic site of plumbagin and also performed a similarity-based library analysis using 2D fingerprints and a docking study. Four compounds as virtual hits were derived from plumbagin. Treatment of Digitaria ciliaris with compound 2, one of four hit compounds, stunted the growth of leaves and the leaf tissue was desiccated or burned within three days. Thus, we expect that compound 2 will be developed as a new herbicide and additionally our strategy will provide helpful information for optimizing lead compounds.

A Solution-Based Temperature Sensor Using the Organic Compound CuTsPc

Directory of Open Access Journals (Sweden)

Shahino Mah Abdullah

2014-06-01

Full Text Available An electrochemical cell using an organic compound, copper (II phthalocyanine-tetrasulfonic acid tetrasodium salt (CuTsPc, has been fabricated and investigated as a solution-based temperature sensor. The capacitance and resistance of the ITO/CuTsPc solution/ITO chemical cell has been characterized as a function of temperature in the temperature range of 25–80 °C. A linear response with minimal hysteresis is observed. The fabricated temperature sensor has shown high consistency and sensitive response towards a specific range of temperature values.

Targeting Anti-Cancer Active Compounds: Affinity-Based Chromatographic Assays

OpenAIRE

de Moraes, Marcela Cristina; Cardoso, Carmen Lucia; Seidl, Claudia; Moaddel, Ruin; Cass, Quezia Bezerra

2016-01-01

Affinity-based chromatography assays encompass the use of solid supports containing immobilized biological targets to monitor binding events in the isolation , identification and/or characterization of bioactive compounds. This powerful bioanalytical technique allows the screening of potential binders through fast analyses that can be directly performed using isolated substances or complex matrices. An overview of the recent researches in frontal and zonal affinity-based chromatography screen...

A Role for Fragment-Based Drug Design in Developing Novel Lead Compounds for Central Nervous System Targets.

Science.gov (United States)

Wasko, Michael J; Pellegrene, Kendy A; Madura, Jeffry D; Surratt, Christopher K

2015-01-01

Hundreds of millions of U.S. dollars are invested in the research and development of a single drug. Lead compound development is an area ripe for new design strategies. Therapeutic lead candidates have been traditionally found using high-throughput in vitro pharmacological screening, a costly method for assaying thousands of compounds. This approach has recently been augmented by virtual screening (VS), which employs computer models of the target protein to narrow the search for possible leads. A variant of VS is fragment-based drug design (FBDD), an emerging in silico lead discovery method that introduces low-molecular weight fragments, rather than intact compounds, into the binding pocket of the receptor model. These fragments serve as starting points for "growing" the lead candidate. Current efforts in virtual FBDD within central nervous system (CNS) targets are reviewed, as is a recent rule-based optimization strategy in which new molecules are generated within a 3D receptor-binding pocket using the fragment as a scaffold. This process not only places special emphasis on creating synthesizable molecules but also exposes computational questions worth addressing. Fragment-based methods provide a viable, relatively low-cost alternative for therapeutic lead discovery and optimization that can be applied to CNS targets to augment current design strategies.

Assessment of combinations of antiandrogenic compounds vinclozolin and flutamide in a yeast based reporter assay.

Science.gov (United States)

Kolle, Susanne N; Melching-Kollmuss, Stephanie; Krennrich, Gerhard; Landsiedel, Robert; van Ravenzwaay, Bennard

2011-08-01

Humans are exposed to a combination of various substances such as cosmetic ingredients, drugs, biocides, pesticides and natural-occurring substances in food. The combined toxicological effects of two or more substances can simply be additive on the basis of response-addition, or it can be greater (synergistic) or smaller (antagonistic) than this. The need to assess combined effects of compounds with endocrine activity is currently discussed for regulatory risk assessment. We have used a well described yeast based androgen receptor transactivation assay YAS to assess the combinatorial effects of vinclozolin and flutamide; both mediating antiandrogenicity via the androgen receptor. Both vinclozolin and flutamide were antiandrogens of similar potency in the YAS assay. In the concentration range tested the two antiandrogens vinclozolin and flutamide did not act synergistically. Concentration additivity was observed in the linear, non-receptor-saturated concentration range. At high concentrations of one of the two substances tested the contribution of the second at lower concentration levels was less than additive. The combined response of both compounds at high concentration levels was also less than additive (saturation effect). At concentration levels which did not elicit a response of the individual compounds, the combination of these compounds also did not elicit a response. Copyright © 2011 Elsevier Inc. All rights reserved.

A network-based multi-target computational estimation scheme for anticoagulant activities of compounds.

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Qian Li

Full Text Available BACKGROUND: Traditional virtual screening method pays more attention on predicted binding affinity between drug molecule and target related to a certain disease instead of phenotypic data of drug molecule against disease system, as is often less effective on discovery of the drug which is used to treat many types of complex diseases. Virtual screening against a complex disease by general network estimation has become feasible with the development of network biology and system biology. More effective methods of computational estimation for the whole efficacy of a compound in a complex disease system are needed, given the distinct weightiness of the different target in a biological process and the standpoint that partial inhibition of several targets can be more efficient than the complete inhibition of a single target. METHODOLOGY: We developed a novel approach by integrating the affinity predictions from multi-target docking studies with biological network efficiency analysis to estimate the anticoagulant activities of compounds. From results of network efficiency calculation for human clotting cascade, factor Xa and thrombin were identified as the two most fragile enzymes, while the catalytic reaction mediated by complex IXa:VIIIa and the formation of the complex VIIIa:IXa were recognized as the two most fragile biological matter in the human clotting cascade system. Furthermore, the method which combined network efficiency with molecular docking scores was applied to estimate the anticoagulant activities of a serial of argatroban intermediates and eight natural products respectively. The better correlation (r = 0.671 between the experimental data and the decrease of the network deficiency suggests that the approach could be a promising computational systems biology tool to aid identification of anticoagulant activities of compounds in drug discovery. CONCLUSIONS: This article proposes a network-based multi-target computational estimation

A network-based multi-target computational estimation scheme for anticoagulant activities of compounds.

Science.gov (United States)

Li, Qian; Li, Xudong; Li, Canghai; Chen, Lirong; Song, Jun; Tang, Yalin; Xu, Xiaojie

2011-03-22

Traditional virtual screening method pays more attention on predicted binding affinity between drug molecule and target related to a certain disease instead of phenotypic data of drug molecule against disease system, as is often less effective on discovery of the drug which is used to treat many types of complex diseases. Virtual screening against a complex disease by general network estimation has become feasible with the development of network biology and system biology. More effective methods of computational estimation for the whole efficacy of a compound in a complex disease system are needed, given the distinct weightiness of the different target in a biological process and the standpoint that partial inhibition of several targets can be more efficient than the complete inhibition of a single target. We developed a novel approach by integrating the affinity predictions from multi-target docking studies with biological network efficiency analysis to estimate the anticoagulant activities of compounds. From results of network efficiency calculation for human clotting cascade, factor Xa and thrombin were identified as the two most fragile enzymes, while the catalytic reaction mediated by complex IXa:VIIIa and the formation of the complex VIIIa:IXa were recognized as the two most fragile biological matter in the human clotting cascade system. Furthermore, the method which combined network efficiency with molecular docking scores was applied to estimate the anticoagulant activities of a serial of argatroban intermediates and eight natural products respectively. The better correlation (r = 0.671) between the experimental data and the decrease of the network deficiency suggests that the approach could be a promising computational systems biology tool to aid identification of anticoagulant activities of compounds in drug discovery. This article proposes a network-based multi-target computational estimation method for anticoagulant activities of compounds by

Coexistence of magnetism and superconductivity in the hole doped FeAs-based superconducting compound

International Nuclear Information System (INIS)

Lu, T.P.; Wu, C.C.; Chou, W.H.; Lan, M.D.

2010-01-01

The magnetic and superconducting properties of the Sm-doped FeAs-based superconducting compound were investigated under wide ranges of temperature and magnetic field. After the systematical magnetic ion substitution, the superconducting transition temperature decreases with increasing magnetic moment. The hysteresis loop of the La 0.87-x Sm x Sr 0.13 FeAsO sample shows a superconducting hysteresis and a paramagnetic background signal. The paramagnetic signal is mainly attributed to the Sm moments. The experiment demonstrates that the coexistence of magnetism and superconductivity in the hole doped FeAs-based superconducting compounds is possible. Unlike the electron doped FeAs-based superconducting compounds SmFeAsOF, the hole doped superconductivity is degraded by the substitution of La by Sm. The hole-doped and electron-doped sides are not symmetric.

Structure-based virtual screening and characterization of a novel IL-6 antagonistic compound from synthetic compound database

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Wang J

2016-12-01

Full Text Available Jing Wang,1,* Chunxia Qiao,1,* He Xiao,1 Zhou Lin,1 Yan Li,1 Jiyan Zhang,1 Beifen Shen,1 Tinghuan Fu,2 Jiannan Feng1 1Department of Molecular Immunology, Beijing Institute of Basic Medical Sciences, 2First Affiliated Hospital of PLA General Hospital, Beijing, People’s Republic of China *These authors contributed equally to this work Abstract: According to the three-dimensional (3D complex structure of (hIL-6·hIL-6R·gp 1302 and the binding orientation of hIL-6, three compounds with high affinity to hIL-6R and bioactivity to block hIL-6 in vitro were screened theoretically from the chemical databases, including 3D-Available Chemicals Directory (ACD and MDL Drug Data Report (MDDR, by means of the computer-guided virtual screening method. Using distance geometry, molecular modeling and molecular dynamics trajectory analysis methods, the binding mode and binding energy of the three compounds were evaluated theoretically. Enzyme-linked immunosorbent assay analysis demonstrated that all the three compounds could block IL-6 binding to IL-6R specifically. However, only compound 1 could effectively antagonize the function of hIL-6 and inhibit the proliferation of XG-7 cells in a dose-dependent manner, whereas it showed no cytotoxicity to SP2/0 or L929 cells. These data demonstrated that the compound 1 could be a promising candidate of hIL-6 antagonist. Keywords: virtual screening, structural optimization, human interlukin-6, small molecular antagonist, XG-7 cells, apoptosis

Comparative analysis of machine learning methods in ligand-based virtual screening of large compound libraries.

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Ma, Xiao H; Jia, Jia; Zhu, Feng; Xue, Ying; Li, Ze R; Chen, Yu Z

2009-05-01

Machine learning methods have been explored as ligand-based virtual screening tools for facilitating drug lead discovery. These methods predict compounds of specific pharmacodynamic, pharmacokinetic or toxicological properties based on their structure-derived structural and physicochemical properties. Increasing attention has been directed at these methods because of their capability in predicting compounds of diverse structures and complex structure-activity relationships without requiring the knowledge of target 3D structure. This article reviews current progresses in using machine learning methods for virtual screening of pharmacodynamically active compounds from large compound libraries, and analyzes and compares the reported performances of machine learning tools with those of structure-based and other ligand-based (such as pharmacophore and clustering) virtual screening methods. The feasibility to improve the performance of machine learning methods in screening large libraries is discussed.

Synthesis, growth, and studies (crystal chemistry, magnetic chemistry) of actinide-based intermetallic compounds and alloys with a 1.1.1 stoichiometry

International Nuclear Information System (INIS)

Kergadallan, Yann

1993-01-01

The first part of this research thesis reports the study of the synthesis and reactivity of intermetallic compounds with a 1.1.1 stoichiometry. It presents the thermal properties of 1.1.1 compounds: general presentation of physical transitions, and of solid solutions and formation heat, application to actinides (reactivity analysis from phase diagrams, techniques of crystal synthesis and crystal growth. It describes experimental techniques: synthesis, determination of fusion temperature by dilatometry, methods used for crystal growth, characterisation techniques (metallography, X ray diffraction on powders, dilatometry). It discusses the obtained results in terms of characterisation of synthesised samples, of crystal growth, and of measurements of fusion temperature. The second part addresses crystal chemistry studies: structure of compounds with a 1.1.1 stoichiometry (Laves structures, Zr, Ti and Pu compounds), techniques of analysis by X-ray diffraction (on powders and on single crystals), result interpretation (UNiX compounds, AnTAl compounds with T being a metal from group VIII, AnTGa compounds, AnNiGe compounds, distance comparison, structure modifications under pressure). The third part concerns physical issues. The author addresses the following topics: physical properties of intermetallic 1.1.1 compounds (magnetism of yttrium phases, behaviour of uranium-based Laves phases, analysis of pseudo-binary diagrams, physical characteristics of uranium-based 1.1.1 compounds, predictions of physical measurements), analysis techniques (Moessbauer spectroscopy, SQUID for Superconducting Quantum Interference Device), and result interpretation

Compound-specific nitrogen isotope analysis of D-alanine, L-alanine, and valine: application of diastereomer separation to delta15N and microbial peptidoglycan studies.

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Takano, Yoshinori; Chikaraishi, Yoshito; Ogawa, Nanako O; Kitazato, Hiroshi; Ohkouchi, Naohiko

2009-01-01

We have developed an analytical method to determine the compound-specific nitrogen isotope compositions of individual amino acid enantiomers using gas chromatography/combustion/isotope ratio mass spectrometry. A novel derivatization of amino acid diastereomers by optically active (R)-(-)-2-butanol or (S)-(+)-2-butanol offers two advantages for nitrogen isotope analysis. First, chromatographic chiral separation can be achieved without the use of chiral stationary-phase columns. Second, the elution order of these compounds on the chromatogram can be switched by a designated esterification reaction. We applied the method to the compound-specific nitrogen isotope analysis of D- and L-alanine in a peptidoglycan derived from the cell walls of cultured bacteria (Firmicutes and Actinobacteria; Enterococcus faecalis, Staphylococcus aureus, Staphylococcus staphylolyticus, Lactobacillus acidophilus, Bacillus subtilis, Micrococcus luteus, and Streptomyces sp.), natural whole bacterial cells (Bacillus subtilis var. natto), (pseudo)-peptidoglycan from archaea (Methanobacterium sp.), and cell wall from eukaryota (Saccharomyces cerevisiae). We observed statistically significant differences in nitrogen isotopic compositions; e.g., delta15N ( per thousand vs air) in Staphylococcus staphylolyticus for d-alanine (19.2 +/- 0.5 per thousand, n = 4) and L-alanine (21.3 +/- 0.8 per thousand, n = 4) and in Bacillus subtilis for D-alanine (6.2 +/- 0.2 per thousand, n = 3) and L-alanine (8.2 +/- 0.4 per thousand, n = 3). These results suggest that enzymatic reaction pathways, including the alanine racemase reaction, produce a nitrogen isotopic difference in amino acid enantiomers, resulting in 15N-depleted D-alanine. This method is expected to facilitate compound-specific nitrogen isotope studies of amino acid stereoisomers.

Degradation of based EPDM dielectric compounds

International Nuclear Information System (INIS)

Galembeck, F.

1988-01-01

The stability of an EPDM compound used as power cables insulation was studied under various conditions of thermal stress. Changes in the dielectric and tensile strenght of the samples were found after the aging. Samples of the EPDM compound were analysed by spectroscopic (photoacoustic, IR) methods showing alterations in its components: Pb 3 O 4 is reduced to PbO and exsuded paraffin is oxidized. Methane is prevalent in the gaseous mixture released by the heated compound and analysed by Gas Chromatography. (author) [pt

Passive sampling as a tool for identifying micro-organic compounds in groundwater.

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Mali, N; Cerar, S; Koroša, A; Auersperger, P

2017-09-01

The paper presents the use of a simple and cost efficient passive sampling device with integrated active carbon with which to test the possibility of determining the presence of micro-organic compounds (MOs) in groundwater and identifying the potential source of pollution as well as the seasonal variability of contamination. Advantage of the passive sampler is to cover a long sampling period by integrating the pollutant concentration over time, and the consequently analytical costs over the monitoring period can be reduced substantially. Passive samplers were installed in 15 boreholes in the Maribor City area in Slovenia, with two sampling campaigns covered a period about one year. At all sampling sites in the first series a total of 103 compounds were detected, and 144 in the second series. Of all detected compounds the 53 most frequently detected were selected for further analysis. These were classified into eight groups based on the type of their source: Pesticides, Halogenated solvents, Non-halogenated solvents, Domestic and personal, Plasticizers and additives, Other industrial, Sterols and Natural compounds. The most frequently detected MO compounds in groundwater were tetrachloroethene and trichloroethene from the Halogenated solvents group. The most frequently detected among the compound's groups were pesticides. Analysis of frequency also showed significant differences between the two sampling series, with less frequent detections in the summer series. For the analysis to determine the origin of contamination three groups of compounds were determined according to type of use: agriculture, urban and industry. Frequency of detection indicates mixed land use in the recharge areas of sampling sites, which makes it difficult to specify the dominant origin of the compound. Passive sampling has proved to be useful tool with which to identify MOs in groundwater and for assessing groundwater quality. Copyright © 2017 Elsevier B.V. All rights reserved.

Multi-view 3D echocardiography compounding based on feature consistency

Science.gov (United States)

Yao, Cheng; Simpson, John M.; Schaeffter, Tobias; Penney, Graeme P.

2011-09-01

Echocardiography (echo) is a widely available method to obtain images of the heart; however, echo can suffer due to the presence of artefacts, high noise and a restricted field of view. One method to overcome these limitations is to use multiple images, using the 'best' parts from each image to produce a higher quality 'compounded' image. This paper describes our compounding algorithm which specifically aims to reduce the effect of echo artefacts as well as improving the signal-to-noise ratio, contrast and extending the field of view. Our method weights image information based on a local feature coherence/consistency between all the overlapping images. Validation has been carried out using phantom, volunteer and patient datasets consisting of up to ten multi-view 3D images. Multiple sets of phantom images were acquired, some directly from the phantom surface, and others by imaging through hard and soft tissue mimicking material to degrade the image quality. Our compounding method is compared to the original, uncompounded echocardiography images, and to two basic statistical compounding methods (mean and maximum). Results show that our method is able to take a set of ten images, degraded by soft and hard tissue artefacts, and produce a compounded image of equivalent quality to images acquired directly from the phantom. Our method on phantom, volunteer and patient data achieves almost the same signal-to-noise improvement as the mean method, while simultaneously almost achieving the same contrast improvement as the maximum method. We show a statistically significant improvement in image quality by using an increased number of images (ten compared to five), and visual inspection studies by three clinicians showed very strong preference for our compounded volumes in terms of overall high image quality, large field of view, high endocardial border definition and low cavity noise.

Multi-view 3D echocardiography compounding based on feature consistency

International Nuclear Information System (INIS)

Yao Cheng; Schaeffter, Tobias; Penney, Graeme P; Simpson, John M

2011-01-01

Echocardiography (echo) is a widely available method to obtain images of the heart; however, echo can suffer due to the presence of artefacts, high noise and a restricted field of view. One method to overcome these limitations is to use multiple images, using the 'best' parts from each image to produce a higher quality 'compounded' image. This paper describes our compounding algorithm which specifically aims to reduce the effect of echo artefacts as well as improving the signal-to-noise ratio, contrast and extending the field of view. Our method weights image information based on a local feature coherence/consistency between all the overlapping images. Validation has been carried out using phantom, volunteer and patient datasets consisting of up to ten multi-view 3D images. Multiple sets of phantom images were acquired, some directly from the phantom surface, and others by imaging through hard and soft tissue mimicking material to degrade the image quality. Our compounding method is compared to the original, uncompounded echocardiography images, and to two basic statistical compounding methods (mean and maximum). Results show that our method is able to take a set of ten images, degraded by soft and hard tissue artefacts, and produce a compounded image of equivalent quality to images acquired directly from the phantom. Our method on phantom, volunteer and patient data achieves almost the same signal-to-noise improvement as the mean method, while simultaneously almost achieving the same contrast improvement as the maximum method. We show a statistically significant improvement in image quality by using an increased number of images (ten compared to five), and visual inspection studies by three clinicians showed very strong preference for our compounded volumes in terms of overall high image quality, large field of view, high endocardial border definition and low cavity noise.

Advances in Base-Free Oxidation of Bio-Based Compounds on Supported Gold Catalysts

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Robert Wojcieszak

2017-11-01

Full Text Available The oxidation of bio-based molecules in general, and of carbohydrates and furanics in particular, is a highly attractive process. The catalytic conversion of renewable compounds is of high importance. Acids and other chemical intermediates issued from oxidation processes have many applications related, especially, to food and detergents, as well as to pharmaceutics, cosmetics, and the chemical industry. Until now, the oxidation of sugars, furfural, or 5-hydroxymethylfurfural has been mainly conducted through biochemical processes or with strong inorganic oxidants. The use of these processes very often presents many disadvantages, especially regarding products separation and selectivity control. Generally, the oxidation is performed in batch conditions using an appropriate catalyst and a basic aqueous solution (pH 7–9, while bubbling oxygen or air through the slurry. However, there is a renewed interest in working in base-free conditions to avoid the production of salts. Actually, this gives direct access to different acids or diacids without laborious product purification steps. This review focuses on processes applying gold-based catalysts, and on the catalytic properties of these systems in the base-free oxidation of important compounds: C5–C6 sugars, furfural, and 5-hydroxymethylfurfural. A better understanding of the chemical and physical properties of the catalysts and of the operating conditions applied in the oxidation reactions is essential. For this reason, in this review we put emphasis on these most impacting factors.

Comparison of Sampling Probe and Thermal Desorber in Hazardous Air Pollutants on Site (HAPSITE) Extended Range (ER) for Analysis of Toxic Organic (TO)-15 Compounds

Science.gov (United States)

2014-03-01

compounds in a bag To prepare 20 ppbv TO-15 compounds in a 5 L ALTEF polypropylene bag (Jensen Inert Products , Coral Springs, FL, USA), 100 mL was taken...Bromopentafluorobenzene (BPFB; an IS)  117  5.70 6,730,000 8,500,000 11,400,000 8,876,667 1,220,000  1,200,000 1,190,000 1,203,333 Ethylbenzene   91  5.91 136 1,960,000...Trichloroethane Toluene Methyl Butyl Ketone (2-Hexanone) Dibromochloromethane 12-Dibromoethane Tetrachloroethylene Chlorobenzene Ethylbenzene p/m

AFFINITY BIOSENSOR BASED ON SCREEN-PRINTED ELECTRODE MODIFIED WITH DNA FOR GENOTOXIC COMPOUNDS DETECTION

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Bambang Kuswandi

2010-06-01

Full Text Available An electrochemical method for the detection of the genotoxic compounds using a DNA-modified electrode was developed. This electrode was successfully used for the electrochemical detection of genotoxic compounds in water samples. The electrochemical results clearly demonstrated that, the development is related to the molecular interaction between the surface-linked DNA obtained from calf thymus and the target compounds, such as pollutants, in order to develop a simple device for rapid screening of genotoxic compounds in environmental samples. The detection of such compounds was measured by their effect on the oxidation signal of the guanine peak of the DNA immobilised on the surface of carbon based Screen-Printed Electrode (SPE in disposable mode, and monitored by square-wave voltametric analysis. The DNA biosensor is able to detect known intercalating and groove-binding genotoxic compounds such as Dioxin, Bisphenol A, PCBs, and Phtalates. Application to real water samples is discussed and reported.   Keywords: electrochemical, screen-printed electrode, DNA biosensor, genotoxic compounds

Evaluating the mutagenic potential of aerosol organic compounds using informatics-based screening

Science.gov (United States)

Decesari, Stefano; Kovarich, Simona; Pavan, Manuela; Bassan, Arianna; Ciacci, Andrea; Topping, David

2018-02-01

Whilst general policy objectives to reduce airborne particulate matter (PM) health effects are to reduce exposure to PM as a whole, emerging evidence suggests that more detailed metrics associating impacts with different aerosol components might be needed. Since it is impossible to conduct toxicological screening on all possible molecular species expected to occur in aerosol, in this study we perform a proof-of-concept evaluation on the information retrieved from in silico toxicological predictions, in which a subset (N = 104) of secondary organic aerosol (SOA) compounds were screened for their mutagenicity potential. An extensive database search showed that experimental data are available for 13 % of the compounds, while reliable predictions were obtained for 82 %. A multivariate statistical analysis of the compounds based on their physico-chemical, structural, and mechanistic properties showed that 80 % of the compounds predicted as mutagenic were grouped into six clusters, three of which (five-membered lactones from monoterpene oxidation, oxygenated multifunctional compounds from substituted benzene oxidation, and hydroperoxides from several precursors) represent new candidate groups of compounds for future toxicological screenings. These results demonstrate that coupling model-generated compositions to in silico toxicological screening might enable more comprehensive exploration of the mutagenic potential of specific SOA components.

A review of plant-based compounds and medicinal plants effective on atherosclerosis

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Mehrnoosh Sedighi

2017-01-01

Full Text Available Atherosclerosis is one of the most important cardiovascular diseases that involve vessels through the development of fatty streaks and plaques. Plant-based compounds can help treat or prevent atherosclerosis through affecting the involved factors. The main purpose of this review article is to investigate and introduce medicinal plants and their potential activities regarding antioxidant properties, effective on lipids level and development of plaque, atherosclerosis, and progression of atherosclerosis as well as the development of cardiovascular disease and ischemia. To search for the relevant articles indexed in Information Sciences Institute, PubMed, Scientific Information Database, IranMedex, and Scopus between 1980 and 2013, with further emphasis on those indexed from 2004 to 2015, we used these search terms: atherosclerosis, antioxidant, cholesterol, inflammation, and the medicinal plants below. Then, the articles with inclusion criteria were used in the final analysis of the findings. Plant-based active compounds, including phenols, flavonoids, and antioxidants, can be effective on atherosclerosis predisposing factors and hence in preventing this disease and associated harmful complications, especially through reducing cholesterol, preventing increase in free radicals, and ultimately decreasing vascular plaque and vascular resistance. Hence, medicinal plants can contribute to treating atherosclerosis and preventing its progression through reducing cholesterolemia, free radicals, inflammation, vascular resistance, and certain enzymes. They, alone or in combination with hypocholesterolemic drugs, can therefore be useful for patients with hyperlipidemia and its complications.

[Matrix transdermal systems for caffeine delivery based on polymer and emulsion compounds].

Science.gov (United States)

Kuznetsova, E G; Kuryleva, O M; Salomatina, L A; Sevast'ianov, V I

2008-01-01

The goal of this work was to develop and test transdermal therapeutic systems for caffeine delivery. In vitro experiments showed that the rate of caffeine diffusion through untreated rabbit skin from a transdermal therapeutic systems based on polymer compound containing 50 mg medicine was 67.2 (9.1 microg/cm2h; for a system based on emulsion compound it was 173 (19 microg/cm2h. Methods for studying the caffeine release rate and quantitative measurement of caffeine content in the emulsion-based transdermal therapeutic system were developed. These methods are required to obtain data for standard drug documentation. The results of in vivo experiments in rabbits showed the absence of irritating effect of the emulsion-based transdermal therapeutic system. The obtained data on the specific efficiency of the transdermal therapeutic systems for caffeine delivery (50 mg) in healthy volunteers showed that this medicine could be used as a nonnarcotic psychoactivator for improving mental and physical activities and attention concentration.

Cysteine-based 3-substituted 1,5-benzoxathiepin derivatives: Two new classes of anti-proliferative agents

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Nawal Mahfoudh

2018-03-01

Full Text Available Two distinct series of the 3-amino-1,5-benzoxathiepin scaffold, derived from L-cysteine, were synthesized and evaluated for their anti-proliferative activity in the breast cancer MDA-MB-231 and MCF-7 cells, and in the ovarian carcinoma SKOV-3 cell line. (3R-Amino-3,4-dihydro-2H-1,5-benzoxathiepin [(R-10] was diversified into two forms: (a by incorporating different amino acids at its position 3, through an amide bond; and (b by construction of the purine ring to give 6-chloro-9-[2-(3,4-dihydro-2H-1,5-benzoxathiepin-(3R-yl]-9H-purine [(R-28]. Nevertheless, when the introduction of iodine was tried at position 2 of the purine ring of (R-28, 2-{[2-(6-chloro-2-iodo-9H-purin-9-ylprop-2-en-1-yl]thio}phenol (34 was obtained. Compound 34 shows activity against cancer cells. Interestingly, 34 inhibits mammosphere formation at the micromolar range, demonstrating activity against cancer stem cells. Although further studies of its targets and mechanism of action are needed, these findings support the therapeutic potential of this compound in cancer.

Modern materials based on refractory compounds

International Nuclear Information System (INIS)

Kosolapova, T.Ya.

1979-01-01

Discussed are the existing methods for synthesizing powders of binary refractory compounds and high-productivity techniques which hold promise as regards the manufacture of highly disperse and pure powders. Plasmochemical synthesis is shown to be an effective method for obtaining practically all carbides, nitrides and borides. A description is given of three main methods for obtaining single crystals of refractory compounds (TiN, TiC, ZrC, ZrB 2 , NbC) fairly perfect in structure and composition. These processes include deposition from vapour-gas phase, melting in arc plasma and crystallization from solutions in metallic melts. The advantages have been shown of the self-propagating high-temperature synthesis of refractory compounds, ensuring the manufacture of products, close in composition to stoichiometric ones simultaneously with forming of items. Mechanical, thermal, abrasive, and resistive characteristics of the above materials are presented

15N liver function tests - concept, validity, clinical use

International Nuclear Information System (INIS)

Faust, H.; Jung, K.; Krumbiegel, P.; Hirschberg, K.; Reinhardt, R.; Junghans, P.

1987-01-01

Several liver function tests using the oral application of a nitrogen compound labelled with 15 N and the subsequent determination of 15 N in a certain fraction of urine by emission spectrometry are described. Because of the key position of the liver in the metabolism of nitrogen compounds the results of these tests allow conclusions concerning disturbances of special liver functions. Instructions for the clinical use of the '[ 15 N]Ammonium Test', '[ 15 N]Hippurate Test' the '[ 15 N]Methacetin Test', and the '[ 15 N]Glycine Test' are given. (author)

The effects of Tb substitution for La on the magnetic properties of LaFe11.5Si1.5 compound

Science.gov (United States)

Imam, H.; Zhang, H. G.; Xu, L.; Zhao, J. L.; Gao, X. X.; Yue, M.

2018-05-01

The structural and magnetic properties of La1-yTbyFe11.5Si1.5 compounds have been investigated. The substituted 5 percent of Tb has remarkably increased the maximum entropy change (-ΔSM) to a value of 25.2 J/kg·K. However, a further increase of Tb leads to a monotonous decrease in the entropy change, mainly due to phase separation. The Tb substitution also can lower the thermal and magnetic hysteresis loss of the system. Another feature of this replacement is that, with Tb content higher than 10 percent, the Curie temperature (TC) starts to increase and reaches 197 K when 30 percent of La is substituted. These results indicate that La1-yTbyFe11.5Si1.5 may be a promising candidate for magnetic refrigeration material in certain temperature range.

Semantics vs Pragmatics of a Compound Word

Science.gov (United States)

Smirnova, Elena A.; Biktemirova, Ella I.; Davletbaeva, Diana N.

2016-01-01

This paper is devoted to the study of correlation between semantic and pragmatic potential of a compound word, which functions in informal speech, and the mechanisms of secondary nomination, which realizes the potential of semantic-pragmatic features of colloquial compounds. The relevance and the choice of the research question is based on the…

A combined Fisher and Laplacian score for feature selection in QSAR based drug design using compounds with known and unknown activities.

Science.gov (United States)

Valizade Hasanloei, Mohammad Amin; Sheikhpour, Razieh; Sarram, Mehdi Agha; Sheikhpour, Elnaz; Sharifi, Hamdollah

2018-02-01

Quantitative structure-activity relationship (QSAR) is an effective computational technique for drug design that relates the chemical structures of compounds to their biological activities. Feature selection is an important step in QSAR based drug design to select the most relevant descriptors. One of the most popular feature selection methods for classification problems is Fisher score which aim is to minimize the within-class distance and maximize the between-class distance. In this study, the properties of Fisher criterion were extended for QSAR models to define the new distance metrics based on the continuous activity values of compounds with known activities. Then, a semi-supervised feature selection method was proposed based on the combination of Fisher and Laplacian criteria which exploits both compounds with known and unknown activities to select the relevant descriptors. To demonstrate the efficiency of the proposed semi-supervised feature selection method in selecting the relevant descriptors, we applied the method and other feature selection methods on three QSAR data sets such as serine/threonine-protein kinase PLK3 inhibitors, ROCK inhibitors and phenol compounds. The results demonstrated that the QSAR models built on the selected descriptors by the proposed semi-supervised method have better performance than other models. This indicates the efficiency of the proposed method in selecting the relevant descriptors using the compounds with known and unknown activities. The results of this study showed that the compounds with known and unknown activities can be helpful to improve the performance of the combined Fisher and Laplacian based feature selection methods.

Introduction to Quality Control in a Compounding Pharmacy.

Science.gov (United States)

Allen, Loyd V

2016-01-01

A quality-based program is vital in every compounding pharmacy to ensure that each preparation is compounded properly and is stable for its expected duration of use. This article discusses quality control, quality assurance, continuous quality improvement, and also describes the components of an in-house (in-pharmacy) quality program, as well as the role of outside laboratories. Copyright© by International Journal of Pharmaceutical Compounding, Inc.

Biodegradation of gasoline compounds (BTEX) in a water works sand filter

DEFF Research Database (Denmark)

Arvin, Erik; Engelsen, P.; Sebber, U.

2004-01-01

Various chemical compounds including aromatic gasoline compounds frequently contaminate drinking water wells in urban areas. Because ground water treatment is simple, usually consisting of aeration/stripping and sand-filtration, it is of significant interest to know the ability of the conventional...... treatment to remove the chemical contaminants. The removal of gasoline compounds was investigated in a two-stage pilot scale sand filter, each with a filter depth of 0.8-1 m and with a filtration rate of 7.6 m/h. The concentrations of aromatic compounds were in the range 7-15 mu g/L, which are realistically...... sand grains). Influent iron concentrations in the range 0-4 mg/L and backwashing did not adversely affect the biodegradation of hydrocarbons. This study has shown that a conventional biological active sand filter can act as an efficient barrier against gasoline compounds, thereby saving the consumer...

Rapid, convenient method for screening imidazole-containing compounds for heme oxygenase inhibition.

Science.gov (United States)

Vlahakis, Jason Z; Rahman, Mona N; Roman, Gheorghe; Jia, Zongchao; Nakatsu, Kanji; Szarek, Walter A

2011-01-01

Sensitive assays for measuring heme oxygenase activity have been based on the gas-chromatographic detection of carbon monoxide using elaborate, expensive equipment. The present study describes a rapid and convenient method for screening imidazole-containing candidates for inhibitory activity against heme oxygenase using a plate reader, based on the spectroscopic evaluation of heme degradation. A PowerWave XS plate reader was used to monitor the absorbance (as a function of time) of heme bound to purified truncated human heme oxygenase-1 (hHO-1) in the individual wells of a standard 96-well plate (with or without the addition of a test compound). The degradation of heme by heme oxygenase-1 was initiated using l-ascorbic acid, and the collected relevant absorbance data were analyzed by three different methods to calculate the percent control activity occurring in wells containing test compounds relative to that occurring in control wells with no test compound present. In the cases of wells containing inhibitory compounds, significant shifts in λ(max) from 404 to near 412 nm were observed as well as a decrease in the rate of heme degradation relative to that of the control. Each of the three methods of data processing (overall percent drop in absorbance over 1.5h, initial rate of reaction determined over the first 5 min, and estimated pseudo first-order reaction rate constant determined over 1.5h) gave similar and reproducible results for percent control activity. The fastest and easiest method of data analysis was determined to be that using initial rates, involving data acquisition for only 5 min once reactions have been initiated using l-ascorbic acid. The results of the study demonstrate that this simple assay based on the spectroscopic detection of heme represents a rapid, convenient method to determine the relative inhibitory activity of candidate compounds, and is useful in quickly screening a series or library of compounds for heme oxygenase inhibition

Self-association and infrared spectres of some heterocyclic compounds based on pyrrol in solid state

International Nuclear Information System (INIS)

Mulloev, N.; Nurulloev, M.; Narziev, B.N.

1993-01-01

Present article is devoted to self-association and infrared spectres of some heterocyclic compounds based on pyrrol in solid state. The study results of self-association specified by molecular hydrogen bonds of some heterocyclic compounds based on pyrrol on spectres of infrared absorption of stretching vibrations of N-H group were considered.

Density of states and T/sub c/ of disordered A15 compounds

International Nuclear Information System (INIS)

Ghosh, A.K.; Strongin, M.

1979-01-01

In this paper various data for the depression of T/sub c/ and N(O) are presented for a wide class of A15 materials. The question of disorder and the limits on T/sub c/ in these materials are discussed

Extraction optimization and pixel-based chemometric analysis of semi-volatile organic compounds in groundwater

DEFF Research Database (Denmark)

Christensen, Peter; Tomasi, Giorgio; Kristensen, Mette

2017-01-01

. In this study, we tested the combination of solid phase extraction (SPE) with dispersive liquid-liquid micro extraction (DLLME), or with stir bar sorptive extraction (SBSE), as an extraction method for semi-VOCs in groundwater. Combining SPE with DLLME or SBSE resulted in better separation of peaks...... in an unresolved complex mixture. SPE-DLLME was chosen as the preferred extraction method. SPE-DLLME covered a larger polarity range (logKo/w 2.0-11.2), had higher extraction efficiency at logKo/w 2.0-3.8 and 5.8-11.2, and was faster compared to SPE-SBSE. SPE-DLLME extraction combined with chemical analysis by gas...... chromatography-mass spectrometry (GC-MS) and pixel-based data analysis of summed extraction ion chromatograms (sEICs) was tested as a new method for chemical fingerprinting of semi-VOCs in 15 groundwater samples. The results demonstrate that SPE-DLLME-GC-MS provides an excellent compromise between compound...

NPACT: Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database.

Science.gov (United States)

Mangal, Manu; Sagar, Parul; Singh, Harinder; Raghava, Gajendra P S; Agarwal, Subhash M

2013-01-01

Plant-derived molecules have been highly valued by biomedical researchers and pharmaceutical companies for developing drugs, as they are thought to be optimized during evolution. Therefore, we have collected and compiled a central resource Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database (NPACT, http://crdd.osdd.net/raghava/npact/) that gathers the information related to experimentally validated plant-derived natural compounds exhibiting anti-cancerous activity (in vitro and in vivo), to complement the other databases. It currently contains 1574 compound entries, and each record provides information on their structure, manually curated published data on in vitro and in vivo experiments along with reference for users referral, inhibitory values (IC(50)/ED(50)/EC(50)/GI(50)), properties (physical, elemental and topological), cancer types, cell lines, protein targets, commercial suppliers and drug likeness of compounds. NPACT can easily be browsed or queried using various options, and an online similarity tool has also been made available. Further, to facilitate retrieval of existing data, each record is hyperlinked to similar databases like SuperNatural, Herbal Ingredients' Targets, Comparative Toxicogenomics Database, PubChem and NCI-60 GI(50) data.

NPACT: Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database

Science.gov (United States)

Mangal, Manu; Sagar, Parul; Singh, Harinder; Raghava, Gajendra P. S.; Agarwal, Subhash M.

2013-01-01

Plant-derived molecules have been highly valued by biomedical researchers and pharmaceutical companies for developing drugs, as they are thought to be optimized during evolution. Therefore, we have collected and compiled a central resource Naturally Occurring Plant-based Anti-cancer Compound-Activity-Target database (NPACT, http://crdd.osdd.net/raghava/npact/) that gathers the information related to experimentally validated plant-derived natural compounds exhibiting anti-cancerous activity (in vitro and in vivo), to complement the other databases. It currently contains 1574 compound entries, and each record provides information on their structure, manually curated published data on in vitro and in vivo experiments along with reference for users referral, inhibitory values (IC50/ED50/EC50/GI50), properties (physical, elemental and topological), cancer types, cell lines, protein targets, commercial suppliers and drug likeness of compounds. NPACT can easily be browsed or queried using various options, and an online similarity tool has also been made available. Further, to facilitate retrieval of existing data, each record is hyperlinked to similar databases like SuperNatural, Herbal Ingredients’ Targets, Comparative Toxicogenomics Database, PubChem and NCI-60 GI50 data. PMID:23203877

Targeting Anti-Cancer Active Compounds: Affinity-Based Chromatographic Assays

Science.gov (United States)

de Moraes, Marcela Cristina; Cardoso, Carmen Lucia; Seidl, Claudia; Moaddel, Ruin; Cass, Quezia Bezerra

2016-01-01

Affinity-based chromatography assays encompass the use of solid supports containing immobilized biological targets to monitor binding events in the isolation , identification and/or characterization of bioactive compounds. This powerful bioanalytical technique allows the screening of potential binders through fast analyses that can be directly performed using isolated substances or complex matrices. An overview of the recent researches in frontal and zonal affinity-based chromatography screening assays, which has been used as a tool in the identification and characterization of new anti-cancer agents, is discussed. In addition, a critical evaluation of the recently emerged ligands fishing assays in complex mixtures is also discussed. PMID:27306095

Polishing compound for plastic surfaces

Science.gov (United States)

Stowell, M.S.

1991-01-01

This invention is comprised of a polishing compound for plastic materials. The compound includes approximately by approximately by weight 25 to 80 parts at least one petroleum distillate lubricant, 1 to 12 parts mineral spirits, 50 to 155 parts abrasive paste, and 15 to 60 parts water. Preferably, the compound includes approximately 37 to 42 parts at least one petroleum distillate lubricant, up to 8 parts mineral spirits, 95 to 110 parts abrasive paste, and 50 to 55 parts water. The proportions of the ingredients are varied in accordance with the particular application. The compound is used on PLEXIGLAS{trademark}, LEXAN{trademark}, LUCITE{trademark}, polyvinyl chloride (PVC), and similar plastic materials whenever a smooth, clear polished surface is desired.

Chiral halogenated Schiff base compounds: green synthesis, anticancer activity and DNA-binding study

Science.gov (United States)

Ariyaeifar, Mahnaz; Amiri Rudbari, Hadi; Sahihi, Mehdi; Kazemi, Zahra; Kajani, Abolghasem Abbasi; Zali-Boeini, Hassan; Kordestani, Nazanin; Bruno, Giuseppe; Gharaghani, Sajjad

2018-06-01

Eight enantiomerically pure halogenated Schiff base compounds were synthesized by reaction of halogenated salicylaldehydes with 3-Amino-1,2-propanediol (R or S) in water as green solvent at ambient temperature. All compounds were characterized by elemental analyses, NMR (1H and 13C), circular dichroism (CD) and FT-IR spectroscopy. FS-DNA binding studies of these compounds carried out by fluorescence quenching and UV-vis spectroscopy. The obtained results revealed that the ligands bind to DNA as: (Rsbnd ClBr) > (Rsbnd Cl2) > (Rsbnd Br2) > (Rsbnd I2) and (Ssbnd ClBr) > (Ssbnd Cl2) > (Ssbnd Br2) > (Ssbnd I2), indicating the effect of halogen on binding constant. In addition, DNA-binding constant of the Ssbnd and R-enantiomers are different from each other. The ligands can form halogen bonds with DNA that were confirmed by molecular docking. This method was also measured the bond distances and bond angles. The study of obtained data can have concluded that binding affinity of the ligands to DNA depends on strength of halogen bonds. The potential anticancer activity of ligands were also evaluated on MCF-7 and HeLa cancer cell lines by using MTT assay. The results showed that the anticancer activity and FS-DNA interaction is significantly dependent on the stereoisomers of Schiff base compounds as R-enantiomers displayed significantly higher activity than S-enantiomers. The molecular docking was also used to illustrate the specific DNA-binding of synthesized compounds and groove binding mode of DNA interaction was proposed for them. In addition, molecular docking results indicated that there are three types of bonds (Hsbnd and X-bond and hX-bond) between synthesized compounds and base pairs of DNA.

Preparation of 15N-13C-fulminic acid

International Nuclear Information System (INIS)

Wilmes, R.; Winnewisser, M.

1993-01-01

The precursor for the title compound was prepared in a three-step synthesis. The 13 C-label was incorporated in the first step employing 2- 13 C-ethyl acetate and the 15 N-label in the last step, using 15 N-sodium nitrite. Upon pyrolysis the precursor forms three fragments, one of them being the title compound. (Author)

Post processing of protein-compound docking for fragment-based drug discovery (FBDD): in-silico structure-based drug screening and ligand-binding pose prediction.

Science.gov (United States)

Fukunishi, Yoshifumi

2010-01-01

For fragment-based drug development, both hit (active) compound prediction and docking-pose (protein-ligand complex structure) prediction of the hit compound are important, since chemical modification (fragment linking, fragment evolution) subsequent to the hit discovery must be performed based on the protein-ligand complex structure. However, the naïve protein-compound docking calculation shows poor accuracy in terms of docking-pose prediction. Thus, post-processing of the protein-compound docking is necessary. Recently, several methods for the post-processing of protein-compound docking have been proposed. In FBDD, the compounds are smaller than those for conventional drug screening. This makes it difficult to perform the protein-compound docking calculation. A method to avoid this problem has been reported. Protein-ligand binding free energy estimation is useful to reduce the procedures involved in the chemical modification of the hit fragment. Several prediction methods have been proposed for high-accuracy estimation of protein-ligand binding free energy. This paper summarizes the various computational methods proposed for docking-pose prediction and their usefulness in FBDD.

A comparative study of the Aurivillius phase ferroelectrics CaBi 4Ti 4O 15 and BaBi 4Ti 4O 15

Science.gov (United States)

Tellier, J.; Boullay, Ph.; Manier, M.; Mercurio, D.

2004-06-01

The room temperature structures of the four-layer Aurivillius phase ferroelectrics CaBi 4Ti 4O 15 and BaBi 4Ti 4O 15 are determined by means of single crystal X-ray diffraction. Regarding the CaBi 4Ti 4O 15 phase, in agreement with the tolerance factor, a significant deformation of the perovskite blocks is observed. The rotation system of the octahedra is typical from even layer Aurivillius phases and leads to the use of the space group A2 1am. For the BaBi 4Ti 4O 15 phase, only a weak variation with respect to the F2 mm space group can be suggested from single crystal X-ray diffraction. A significant presence of Ba atoms in the [ M2O 2] slabs is confirmed in agreement with the previous works but specific Ba 2+ and Bi 3+ sites have to be considered due to the large difference in bounding requirement of these cations. Possible origins for the ferroelectric relaxor behavior of the Ba-based compound are discussed in view of the presented structural analyses.

Materials Chemistry and Performance of Silicone-Based Replicating Compounds.

Energy Technology Data Exchange (ETDEWEB)

Brumbach, Michael T.; Mirabal, Alex James; Kalan, Michael; Trujillo, Ana B; Hale, Kevin

2014-11-01

Replicating compounds are used to cast reproductions of surface features on a variety of materials. Replicas allow for quantitative measurements and recordkeeping on parts that may otherwise be difficult to measure or maintain. In this study, the chemistry and replicating capability of several replicating compounds was investigated. Additionally, the residue remaining on material surfaces upon removal of replicas was quantified. Cleaning practices were tested for several different replicating compounds. For all replicating compounds investigated, a thin silicone residue was left by the replica. For some compounds, additional inorganic species could be identified in the residue. Simple solvent cleaning could remove some residue.

Rule-based Approach on Extraction of Malay Compound Nouns in Standard Malay Document

Science.gov (United States)

Abu Bakar, Zamri; Kamal Ismail, Normaly; Rawi, Mohd Izani Mohamed

2017-08-01

Malay compound noun is defined as a form of words that exists when two or more words are combined into a single syntax and it gives a specific meaning. Compound noun acts as one unit and it is spelled separately unless an established compound noun is written closely from two words. The basic characteristics of compound noun can be seen in the Malay sentences which are the frequency of that word in the text itself. Thus, this extraction of compound nouns is significant for the following research which is text summarization, grammar checker, sentiments analysis, machine translation and word categorization. There are many research efforts that have been proposed in extracting Malay compound noun using linguistic approaches. Most of the existing methods were done on the extraction of bi-gram noun+noun compound. However, the result still produces some problems as to give a better result. This paper explores a linguistic method for extracting compound Noun from stand Malay corpus. A standard dataset are used to provide a common platform for evaluating research on the recognition of compound Nouns in Malay sentences. Therefore, an improvement for the effectiveness of the compound noun extraction is needed because the result can be compromised. Thus, this study proposed a modification of linguistic approach in order to enhance the extraction of compound nouns processing. Several pre-processing steps are involved including normalization, tokenization and tagging. The first step that uses the linguistic approach in this study is Part-of-Speech (POS) tagging. Finally, we describe several rules-based and modify the rules to get the most relevant relation between the first word and the second word in order to assist us in solving of the problems. The effectiveness of the relations used in our study can be measured using recall, precision and F1-score techniques. The comparison of the baseline values is very essential because it can provide whether there has been an improvement

Physical Compatibility of Magnesium Sulfate and Sodium Bicarbonate in a Pharmacy-compounded Bicarbonate-buffered Hemofiltration Solution

Science.gov (United States)

Moriyama, Brad; Henning, Stacey A.; Jin, Haksong; Kolf, Mike; Rehak, Nadja N.; Danner, Robert L.; Walsh, Thomas J.; Grimes, George J.

2011-01-01

PURPOSE To assess the physical compatibility of magnesium sulfate and sodium bicarbonate in a pharmacy-compounded bicarbonate-buffered hemofiltration solution used at the National Institutes of Health Clinical Center (http://www.cc.nih.gov). METHODS Two hemofiltration fluid formulations with a bicarbonate of 50 mEq/L and a magnesium of 1.5 mEq/L or 15 mEq/L were prepared in triplicate with an automated compounding device. The hemofiltration solution with a bicarbonate of 50 mEq/L and a magnesium of 1.5 mEq/L contains the maximum concentration of additives that we use in clinical practice. The hemofiltration solution of 15 mEq/L of magnesium and 50 mEq/L of bicarbonate was used to study the physicochemical properties of this interaction. The solutions were stored without light protection at 22 to 25 °C for 48 hours. Physical compatibility was assessed by visual inspection and microscopy. The pH of the solutions was assayed at 3 to 4 hours and 52 to 53 hours after compounding. In addition, electrolyte and glucose concentrations in the solutions were assayed at two time points after preparation: 3 to 4 hours and 50 to 51 hours. RESULTS No particulate matter was observed by visual and microscopic inspection in the compounded hemofiltration solutions at 48 hours. Electrolyte and glucose concentrations and pH were similar at both time points after solution preparation. CONCLUSION Magnesium sulfate (1.5 mEq/L) and sodium bicarbonate (50 mEq/L) were physically compatible in a pharmacy-compounded bicarbonate-buffered hemofiltration solution at room temperature without light protection at 48 hours. PMID:20237384

Contact-based ligand-clustering approach for the identification of active compounds in virtual screening

Directory of Open Access Journals (Sweden)

Mantsyzov AB

2012-09-01

Full Text Available Alexey B Mantsyzov,1 Guillaume Bouvier,2 Nathalie Evrard-Todeschi,1 Gildas Bertho11Université Paris Descartes, Sorbonne, Paris, France; 2Institut Pasteur, Paris, FranceAbstract: Evaluation of docking results is one of the most important problems for virtual screening and in silico drug design. Modern approaches for the identification of active compounds in a large data set of docked molecules use energy scoring functions. One of the general and most significant limitations of these methods relates to inaccurate binding energy estimation, which results in false scoring of docked compounds. Automatic analysis of poses using self-organizing maps (AuPosSOM represents an alternative approach for the evaluation of docking results based on the clustering of compounds by the similarity of their contacts with the receptor. A scoring function was developed for the identification of the active compounds in the AuPosSOM clustered dataset. In addition, the AuPosSOM efficiency for the clustering of compounds and the identification of key contacts considered as important for its activity, were also improved. Benchmark tests for several targets revealed that together with the developed scoring function, AuPosSOM represents a good alternative to the energy-based scoring functions for the evaluation of docking results.Keywords: scoring, docking, virtual screening, CAR, AuPosSOM

Stable isotope 15N-urea and clinical research in nephrology

International Nuclear Information System (INIS)

Sugino, Nobuhiro; Arai, Junko; Akimoto, Mitsuko; Miwa, Toichiro; Takuma, Takehide

1990-01-01

Stable isotope 15 N-compound, 15 N-urea, is useful marker to investigate nitrogen metabolism in clinical nephrology, particularly in chronic renal failure or dialysis. 15 N-urea incorporation into plasma albumin in addition to plasma 15 N disappearance was studied in 6 patients with endstage chronic renal failure. As a result, only minor fraction of administered 15 N-urea was incorporated into albumin in this study. In addition, it was also confirmed that high energy diet may promote protein synthesis through 15 N incorporation to plasma amino acids, such as alanine, in these patients with low protein meal. Therefore, administration of 15 N-compound to human subjects may contribute to provide us the important informations on nitrogen metabolism. For instance, urea kinetics are described in the endstage chronic renal failure in this review. However, less expensive 15 N-compounds should be provided and more simple but accurate measurement of 15 N activity should be developed for the further clinical application of the stable isotope. (author)

Volumetric study of (diethylamine + water) mixtures between (278.15 and 308.15) K

International Nuclear Information System (INIS)

Lampreia, Isabel M.S.; Dias, Florbela A.; Mendonca, Angela F.S.S.

2004-01-01

Densities have been measured for aqueous mixtures of diethylamine at the temperatures: (278.15, 288.15, 293.15, 298.15, and 308.15) K, for the entire composition range. The data have been used to calculate apparent molar, excess molar and excess partial molar volumes. Limiting values of excess partial molar volumes and expansions have been derived as well. The discussion has been undertaken comparing the obtained values with those of parent studies in related compounds

Solubility of carbon monoxide in bio-oil compounds

International Nuclear Information System (INIS)

Qureshi, Muhammad Saad; Le Nedelec, Tom; Guerrero-Amaya, Hernando; Uusi-Kyyny, Petri; Richon, Dominique; Alopaeus, Ville

2017-01-01

Highlights: • CO solubility was measured in four bio-oil compounds using static-analytic VLE equipment. • A comparison on the performance of different EoS (PC-SAFT, SRK and PR) was made. • Modelling of polar compounds with Polar PC-SAFT was tested. • Polar PC-SAFT is not needed for weakly polar compounds (μ < 1.0 D). - Abstract: The solubility of carbon monoxide is measured in four different bio-oil compounds (furan, diacetyl, 2-methylfuran, and trans-crotonaldehyde) at temperatures (273.15, 283.15, 298.15, and 323.15 K) and pressures up to 8 MPa using a static-analytical VLE measurement method. The equipment was validated by measuring the solubility of CO 2 in methanol at 298.15 K and pressures (P = 2.9–5.7 MPa). The results were compared with the abundantly available literature values. PC-SAFT, Polar PC-SAFT (PPC-SAFT), and Cubic (SRK, PR) EoS, part of commercial process simulator Aspen Plus V. 8.6, are used here for modelling purpose. The pure component parameters needed for PC-SAFT and PPC-SAFT EoS models, are regressed using the experimental liquid density and vapour pressure data of the pure components. It was observed that furan, 2-methylfuran and diacetyl, having weak dipole moments (μ < 1.0 D), could be modelled reasonably well without the addition of polar contribution using conventional PC-SAFT, while it is recommended to use PPC-SAFT for the description of a polar compound like trans-crotonaldehyde (μ ∼ 3.67 D). It was observed that SRK and PR EoS have similar predictive ability in comparison to PC-SAFT for a mixture of CO with weakly polar compounds in this study. A comparison between the performances of EoS models was made in two ways: first by setting the binary interaction parameter k ij to zero, and second by adjusting a temperature-dependent binary interaction parameter (k ij ). All the models perform with comparable accuracy with adjusted binary interaction parameters. However, due to the large differences between the chemical and

Resonances in the nuclear reactions 15N + 12C and 15N + 16O

International Nuclear Information System (INIS)

Monnehan, G.A.

1987-06-01

The reaction 12 C + 15 N have been studied at 15 N beam energies between 30 and 70 MeV. For each reaction, about twelve residual nuclei have been identified through the γ-ray detection method. Excitation functions were obtained for the fusion and peripheral channels. Resonances are seen in the channels containing at least one α particle at energies below 50 MeV. At higher energies, strong structures are observed in the direct reaction channels. The evolution of the fusion cross section is well reproduced by a model based on the statistical desexcitation of the compound nucleus if the discrete states of the residual nuclei are taken into account. The favourable observation of resonant phenomena in 15 N induced reactions can be understood in terms of a small number of channels open to the grazing wave. In the range 50 to 60 MeV, there is a strong coupling between the fusion and the direct reaction channels. The occurrence of resonances above E lab = 50 MeV in the peripheral channels is explained with the band crossing and effective barrier models. In the 15 N induced reactions, the absorption of the surface waves is weak [fr

Studies on the effect of a newly synthesized Schiff base compound from phenazone and vanillin on the corrosion of steel in 2M HCl

International Nuclear Information System (INIS)

Emreguel, Kaan C.; Hayvali, Mustafa

2006-01-01

The inhibiting action of a Schiff base 4-[(4-hydroxy-3-hydroxymethyl-benzylidene)-amino]-1,5-dimethyl-2-phenyl-1,2 -dihydro-pyrazol-3-one (phv), derived from 4-amino-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (phz) and 4-hydroxy-3-methoxy-benzaldehyde (vn), towards the corrosion behavior of steel in 2M HCl solution has been studied using weight loss, polarization and electrochemical impedance spectroscopy (EIS) techniques. Although vn and phz were found to retard the corrosion rate of steel, the compound synthesized from vn and phz was seen to retard the corrosion rate even more. At constant temperature, the corrosion rate decreases with increasing inhibitor concentration. However, at any inhibitor concentration the increase in temperature leads to an increase in the corrosion rate of steel. The activations energies, ΔE a , as well as other thermodynamic parameters (ΔG ads 0 , ΔH ads 0 ) for the inhibitor process were calculated. The inhibitor efficiencies calculated from all the applied methods were in agreement and were found to be in the order: phv>phz>vn

Microstructure, mechanical properties, and thermoelectric properties of hot-extruded p-type Te-doped Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} compounds

Energy Technology Data Exchange (ETDEWEB)

Park, K; Seo, J; Lee, C

1997-07-01

The p-type Bi{sub 0.5}Sb{sub 1.5}Te{sub 3} compounds with Te dopant (4.0 and 6.0 wt%) and without dopant were fabricated by hot extrusion in the temperature range of 300 to 510 C under an extrusion ratio of 20:1. The undoped and Te doped compounds were highly dense and showed high crystalline quality. The grains contained many dislocations and were fine equiaxed ({approximately}1.0 {micro}m) owing to the dynamic recrystallization during the extrusion. The hot extrusion gave rise to the preferred orientation of grains. The bending strength and the figure of merit of the undoped and Te doped compounds were increased with increasing the extrusion temperature. The Te dopant significantly increased the figure of merit. The values of the figure of merit of the undoped and 4.0 wt% Te-doped compounds hot extruded at 440 C were 2.11 x 10{sup {minus}3}/K and 2.94 x 10{sup {minus}3}/K, respectively.

Process for production of a borohydride compound

Science.gov (United States)

Allen, Nathan Tait; Butterick, III, Robert; Chin, Arthur Achhing; Millar, Dean Michael; Molzahn, David Craig

2014-08-19

A process for production of a borohydride compound M(BH.sub.4).sub.y. The process has three steps. The first step combines a compound of formula (R.sup.1O).sub.yM with aluminum, hydrogen and a metallic catalyst containing at least one metal selected from the group consisting of titanium, zirconium, hafnium, niobium, vanadium, tantalum and iron to produce a compound of formula M(AlH.sub.3OR.sup.1).sub.y, wherein R.sup.1 is phenyl or phenyl substituted by at least one alkyl or alkoxy group; M is an alkali metal, Be or Mg; and y is one or two; wherein the catalyst is present at a level of at least 200 ppm based on weight of aluminum. The second step combines the compound of formula M(AlH.sub.3OR.sup.1).sub.y with a borate, boroxine or borazine compound to produce M(BH.sub.4).sub.y and a byproduct mixture containing alkali metal and aluminum aryloxides. The third step separates M(BH.sub.4).sub.y from the byproduct mixture.

A novel tyrosinase biosensor based on hydroxyapatite-chitosan nanocomposite for the detection of phenolic compounds

International Nuclear Information System (INIS)

Lu Limin; Zhang Li; Zhang Xiaobing; Huan Shuangyan; Shen Guoli; Yu Ruqin

2010-01-01

A novel tyrosinase biosensor based on hydroxyapatite nanoparticles (nano-HA)-chitosan nanocomposite has been developed for the detection of phenolic compounds. The uniform and size controlled nano-HA was synthesized by hydrothermal method, and its morphological characterization was examined by transmission electron microscope (TEM). Tyrosinase was then immobilized on a nano-HA-chitosan nanocomposite-modified gold electrode. Electrochemical impedance spectroscopy and cyclic voltammetry were used to characterize the sensing film. The prepared biosensor was applied to determine phenolic compounds by monitoring the reduction signal of the biocatalytically produced quinone species at -0.2 V (vs. saturated calomel electrode). The effects of the pH, temperature and applied potential on the biosensor performance were investigated, and experimental conditions were optimized. The biosensor exhibited a linear response to catechol over a wide concentration range from 10 nM to 7 μM, with a high sensitivity of 2.11 x 10 3 μA mM -1 cm -2 , and a limit of detection down to 5 nM (based on S/N = 3). The apparent Michaelis-Menten constants of the enzyme electrode were estimated to be 3.16, 1.31 and 3.52 μM for catechol, phenol and m-cresol, respectively. Moreover, the stability and reproducibility of this biosensor were evaluated with satisfactory results.

Supercritical fluid extraction of volatile and non-volatile compounds from Schinus molle L.

Directory of Open Access Journals (Sweden)

M. S. T. Barroso

2011-06-01

Full Text Available Schinus molle L., also known as pepper tree, has been reported to have antimicrobial, antifungal, anti-inflammatory, antispasmodic, antipyretic, antitumoural and cicatrizing properties. This work studies supercritical fluid extraction (SFE to obtain volatile and non-volatile compounds from the aerial parts of Schinus molle L. and the influence of the process on the composition of the extracts. Experiments were performed in a pilot-scale extractor with a capacity of 1 L at pressures of 9, 10, 12, 15 and 20 MPa at 323.15 K. The volatile compounds were obtained by CO2 supercritical extraction with moderate pressure (9 MPa, whereas the non-volatile compounds were extracted at higher pressure (12 to 20 MPa. The analysis of the essential oil was carried out by GC-MS and the main compounds identified were sabinene, limonene, D-germacrene, bicyclogermacrene, and spathulenol. For the non-volatile extracts, the total phenolic content was determined by the Folin-Ciocalteau method. Moreover, one of the goals of this study was to compare the experimental data with the simulated yields predicted by a mathematical model based on mass transfer. The model used requires three adjustable parameters to predict the experimental extraction yield curves.

Check specific compounds lyrics Saeb and Biddle, based on syntactic and semantic core composition

Directory of Open Access Journals (Sweden)

khodabakhsh asadollahi

2016-02-01

Full Text Available Saebe Tabrizi and Bidele Dehlavi of the most famous poets in Hindi, which each in turn, the Iranian branch and Hindi Hindi style, the lyrics have been changed in this period. Most scholars who have studied the poetry Biddle to research, Specific compounds as one of the most important factors in a monopoly ambiguity Biddle poetry and in the making and meaning of these compounds have less reflection. Here are the lyrics to rely on dictionary and Biddle, the Iranian branch of specific compounds in both Hindi and Hindi poetry style is investigated. Combining both his first two exocentric and endocentric compounds is assorted, Based on Syntactic relations, various models of deep structure and composition relationships is presented. Saeb specific compounds and Biddle in deep syntactic relations as diverse as the relationship between the finite, nominative, accusative, amendment and so on.The semantic structure, certain combinations of the two poets more varied combinations are commonplace in standard language, so that some of the compounds exist in terms of meaning in language

Impact of high-intensity pulsed electric fields on bioactive compounds in Mediterranean plant-based foods.

Science.gov (United States)

Elez-Martínez, Pedro; Soliva-Fortuny, Robert; Martín-Belloso, Olga

2009-05-01

Novel non-thermal processing technologies such as high-intensity pulsed electric field (HIPEF) treatments may be applied to pasteurize plant-based liquid foods as an alternative to conventional heat treatments. In recent years, there has been an increasing interest in HIPEF as a way of preserving and extending the shelf-life of liquid products without the quality damage caused by heat treatments. However, less attention has been paid to the effects of HIPEF on minor constituents of these products, namely bioactive compounds. This review is a state-of-the-art update on the effects of HIPEF treatments on health-related compounds in plants of the Mediterranean diet such as fruit juices, and Spanish gazpacho. The relevance of HIPEF-processing parameters on retaining plant-based bioactive compounds will be discussed.

Atom-type-based AI topological descriptors: application in structure-boiling point correlations of oxo organic compounds.

Science.gov (United States)

Ren, Biye

2003-01-01

Structure-boiling point relationships are studied for a series of oxo organic compounds by means of multiple linear regression (MLR) analysis. Excellent MLR models based on the recently introduced Xu index and the atom-type-based AI indices are obtained for the two subsets containing respectively 77 ethers and 107 carbonyl compounds and a combined set of 184 oxo compounds. The best models are tested using the leave-one-out cross-validation and an external test set, respectively. The MLR model produces a correlation coefficient of r = 0.9977 and a standard error of s = 3.99 degrees C for the training set of 184 compounds, and r(cv) = 0.9974 and s(cv) = 4.16 degrees C for the cross-validation set, and r(pred) = 0.9949 and s(pred) = 4.38 degrees C for the prediction set of 21 compounds. For the two subsets containing respectively 77 ethers and 107 carbonyl compounds, the quality of the models is further improved. The standard errors are reduced to 3.30 and 3.02 degrees C, respectively. Furthermore, the results obtained from this study indicate that the boiling points of the studied oxo compound dominantly depend on molecular size and also depend on individual atom types, especially oxygen heteroatoms in molecules due to strong polar interactions between molecules. These excellent structure-boiling point models not only provide profound insights into the role of structural features in a molecule but also illustrate the usefulness of these indices in QSPR/QSAR modeling of complex compounds.

Antiproliferative Compounds of Cyphostemma greveana from a Madagascar Dry Forest[1

OpenAIRE

Cao, Shugeng; Hou, Yanpeng; Brodie, Peggy; Miller, James S.; Randrianaivo, Richard; Rakotobe, Etienne; Rasamison, Vincent E.; Kingston, David G. I.

2011-01-01

Bioassay-guided fractionation of the EtOH extracts obtained from a plant identified as Cyphostemma greveana Desc. (Vitaceae) led to the identification of one macrolide, lasiodiplodin (1), three sesquiterpenoids, 12-hydroxy-15-oxo-selina-4,1l-diene (2), 1β,6α-dihydroxyeudesm-4(15)-ene (3), and (7R*)-opposit-4(15)-ene-1β,7-diol (5), and the new diterpenoid, 16,18-dihydroxykolavenic acid lactone (4). All the isolates were tested against the A2780 human ovarian cancer cell line, and compound 4 an...

Organic Compounds Complexify Transport in the Amargosa Desert—The Case for Phytotritiation

Science.gov (United States)

Stonestrom, D. A.; Luo, W.; Andraski, B. J.; Baker, R. J.; Maples, S.; Mayers, C. J.; Young, M. B.

2014-12-01

Civilian low-level radioactive waste containing organic compounds was disposed in 2- to 15-m deep unlined trenches in a 110-m deep unsaturated zone at the present-day USGS Amargosa Desert Research Site. Tritium represents the plurality of disposed activity. A plume of gas-phase contaminants surrounds the disposal area, with 60 distinct volatile organic compounds (VOCs) identified to date. The distribution of tritiated water in the unsaturated zone surrounding the disposal area is highly enigmatic, with orders of magnitude separating observed levels from those predicted by multiphase models of mass and energy transport. Peaks of tritium and VOCs are coincidently located in sediments tens of meters below the root zone, suggesting abiotic stratigraphic control on lateral transport at depth. Surprisingly, the highest observed levels of tritium occur at a depth of about 1.5 m, the base of the creosote-bush plant-community root zone, where levels of waste-derived VOCs are low (approaching atmospheric levels). Bulk water-vapor samples from shallow and deep unsaturated-zone profile hot spots were trapped as water ice in cold fingers immersed in dry ice-isopropyl alcohol filled Dewar flasks, then melted and sequentially extracted by purge-and-trap VOC degassing followed by elution through activated carbon solid-phase extraction (SPE) cartridges. Analysis of tritium activities and mass spectrometer results indicate that over 98% of tritium activity at depth is present as water, whereas about 15% of basal root zone tritium activity is present as organic compounds trapped with the water. Of these, the less-volatile compound group removed by SPE accounted for about 85% of the organic tritium activity, with mass spectrometry identifying 2-ethyl-1-hexanol as the principal compound removed. This plant-produced fatty alcohol is ubiquitous in the root zone of creosote-bush communities and represents a family of hydroxyl-containing plant produced compounds that give the plants their

Metabolomics-Based Screening of Biofilm-Inhibitory Compounds against Pseudomonas aeruginosa from Burdock Leaf

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Zaixiang Lou

2015-09-01

Full Text Available Screening of anti-biofilm compounds from the burdock leaf based on metabolomics is reported here. The crystal violet assay indicated 34% ethanol elution fraction of burdock leaf could completely inhibit biofilm formation of Pseudomonas aeruginosa at 1 mg·mL−1. Then, the chemical composition of burdock leaf fraction was analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS and 11 active compounds (chlorogenic acid, caffeic acid, p-coumaric acid, quercetin, ursolic acid, rutin, cynarin, luteolin, crocin, benzoic acid, and Tenacissoside I were identified. Lastly, UPLC-MS analysis was employed to obtain the metabolic fingerprints of burdock leaf fractions before and after inhibiting the biofilm of Pseudomonas aeruginosa. The metabolic fingerprints were transformed to data, analyzed with PLS-DA (partial least squares discriminant analysis and the peaks whose area was significantly changed were found out. Thus, 81 compounds were screened as potential anti-biofilm ingredients. Among them, rutin, ursolic acid, caffeic acid, p-coumaric acid and quercetin were identified and confirmed as the main anti-biofilm compounds in burdock leaf. The study provided basic anti-biofilm profile data for the compounds in burdock leaf, as well as provided a convenient method for fast screening of anti-biofilm compounds from natural plants.

Assessment of Non-Sterile Pharmaceutical Compounding Practices ...

African Journals Online (AJOL)

A descriptive cross-sectional survey was conducted to assess the practices of non-sterile pharmaceutical compounding in selected 42 community and 3 hospital pharmacies in Addis Ababa, Ethiopia from 01 April, 2016 to 15 May, 2016. The study revealed that the most commonly prescribed and compounded non-sterile ...

Optimization of Mechanical, Dynamical and Thermal Properties of a High Performance Tread Compound for Radial Tires

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Mir Hamid Reza Ghoreishy

2013-06-01

Full Text Available A high performance passenger tire tread compound was optimized for its mechanical, dynamical and thermal properties. A reference compound was based on a blend of SBR and BR, sulfur and other ingredients without accelerator, carbon black and aromatic oil. The effects of CBS/TMTD and TBBS/TMTD as accelerator systems were studied with different quantities and the best accelerator system was chosen. Then, the blends of N330 and N550 carbon blacks were added in different quantities and the properties of these samples were studied to determine the best carbon black blend. Finally, the effect of different quantities of aromatic oil was investigated and the optimized quantity of aromatic oil and the final properties of tire tread compound were defined. The mechanical and dynamical tests were carried out on appropriate samples to determine tensile strength, elongation-at-break, fatigue-to-failure, abrasion resistance, hardness, resilience, dynamical-mechanical properties and temperature rise due to the heat build-up. The results showed that the compound containing 0.8 phr CBS, 0.7 phr TMTD, 40 phr N330,20 phr N550 and 15 phr aromatic oils demonstrated the best properties.

Synthesis of [1,3 - 15 N2] uracil

International Nuclear Information System (INIS)

Chiriac, M.; Axente, D.

2001-01-01

The synthesis of 15 N labelled uracil, using CO( 15 NH 2 ) 2 as starting material, is presented. The experimental procedure is an adaptation of the synthesis methods for the corresponding unlabelled compounds. Urea- 15 N 2 used as starting material was obtained from H 15 NO 3 (99 at.% 15 N) produced at National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj-Napoca.The uracil structure was determined using the mass spectrometry method and the isotopic labelling was determined by the same method on the molecular compound. The synthesis scheme of (1,3- 15 N 2 ) uracil is presented. (authors)

Synthesis of labeled compounds

International Nuclear Information System (INIS)

Whaley, T.W.

1977-01-01

Intermediate compounds labeled with 13 C included methane, sodium cyanide, methanol, ethanol, and acetonitrile. A new method for synthesizing 15 N-labeled 4-ethylsulfonyl-1-naphthalene-sulfonamide was developed. Studies were conducted on pathways to oleic-1- 13 C acid and a second pathway investigated was based on carbonation of 8-heptadecynylmagnesium bromide with CO 2 to prepare sterolic acid. Biosynthetic preparations included glucose- 13 C from starch isolated from tobacco leaves following photosynthetic incubation with 13 CO 2 and galactose- 13 C from galactosylglycerol- 13 C from kelp. Research on growth of organisms emphasized photosynthetic growth of algae in which all cellular carbon is labeled. Preliminary experiments were performed to optimize the growth of Escherichia coli on sodium acetate- 13 C

15N-Labelling and structure determination of adamantylated azolo-azines in solution

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Sergey L. Deev

2017-11-01

Full Text Available Determining the accurate chemical structures of synthesized compounds is essential for biomedical studies and computer-assisted drug design. The unequivocal determination of N-adamantylation or N-arylation site(s in nitrogen-rich heterocycles, characterized by a low density of hydrogen atoms, using NMR methods at natural isotopic abundance is difficult. In these compounds, the heterocyclic moiety is covalently attached to the carbon atom of the substituent group that has no bound hydrogen atoms, and the connection between the two moieties of the compound cannot always be established via conventional 1H-1H and 1H-13C NMR correlation experiments (COSY and HMBC, respectively or nuclear Overhauser effect spectroscopy (NOESY or ROESY. The selective incorporation of 15N-labelled atoms in different positions of the heterocyclic core allowed for the use of 1H-15N (JHN and 13C-15N (JCN coupling constants for the structure determinations of N-alkylated nitrogen-containing heterocycles in solution. This method was tested on the N-adamantylated products in a series of azolo-1,2,4-triazines and 1,2,4-triazolo[1,5-a]pyrimidine. The syntheses of adamantylated azolo-azines were based on the interactions of azolo-azines and 1-adamatanol in TFA solution. For azolo-1,2,4-triazinones, the formation of mixtures of N-adamantyl derivatives was observed. The JHN and JCN values were measured using amplitude-modulated 1D 1H spin-echo experiments with the selective inversion of the 15N nuclei and line-shape analysis in the 1D 13С spectra acquired with selective 15N decoupling, respectively. Additional spin–spin interactions were detected in the 15N-HMBC spectra. NMR data and DFT (density functional theory calculations permitted to suggest a possible mechanism of isomerization for the adamantylated products of the azolo-1,2,4-triazines. The combined analysis of the JHN and JCN couplings in 15N-labelled compounds provides an efficient method for the structure

Food processing strategies to enhance phenolic compounds bioaccessibility and bioavailability in plant-based foods.

Science.gov (United States)

Ribas-Agustí, Albert; Martín-Belloso, Olga; Soliva-Fortuny, Robert; Elez-Martínez, Pedro

2017-06-13

Phenolic compounds are important constituents of plant-based foods, as their presence is related to protective effects on health. To exert their biological activity, phenolic compounds must be released from the matrix during digestion in an absorbable form (bioaccessible) and finally absorbed and transferred to the bloodstream (bioavailable). Chemical structure and matrix interactions are some food-related factors that hamper phenolic compounds bioaccessibility and bioavailability, and that can be counteracted by food processing. It has been shown that food processing can induce chemical or physical modifications in food that enhance phenolic compounds bioaccessibility and bioavailability. These changes include: (i) chemical modifications into more bioaccessible and bioavailable forms; (ii) cleavage of covalent or hydrogen bonds or hydrophobic forces that attach phenolic compounds to matrix macromolecules; (iii) damaging microstructural barriers such as cell walls that impede the release from the matrix; and (iv) create microstructures that protect phenolic compounds until they are absorbed. Indeed, food processing can produce degradation of phenolic compounds, however, it is possible to counteract it by modulating the operating conditions in favor of increased bioaccessibility and bioavailability. This review compiles the current knowledge on the effects of processing on phenolic compounds bioaccessibility or bioavailability, while suggesting new guidelines in the search of optimal processing conditions as a step forward towards the design of healthier foods.

The synthesis, characterization and optical properties of novel 1,3,4-oxadiazole-containing imidazo[1,5-a]pyridine derivatives

International Nuclear Information System (INIS)

Ge Yanqing; Hao Benqian; Duan Guiyun; Wang Jianwu

2011-01-01

A series of novel substituted 1,3,4-oxadiazole derivatives were synthesized by the reaction of 3-butyl-1-chloroimidazo[1,5-a]pyridine-7-carbohydrazide with propionyl chloride and substituted benzoic chloride in the presence of phosphorus oxychloride. The compounds were characterized using IR, 1 H NMR, 13 C NMR and HRMS. Absorption and fluorescence spectra were measured in dichloromethane; an intense absorption maxima was noted at ca. 290 nm and emission maxima was noted at ca. 470 nm. The absorption spectra of the 1,3,4-oxadiazole derivatives reveal that a phenyl and an ethyl group attached to the 1,3,4-oxadiazole ring markedly influenced the maximum absorption. The structures based on density function theory (DFT) calculation show planar configurations for the compounds. The calculated molecular orbital correlates well with their absorption. - Research highlights: → Novel imidazo[1,5-a]pyridine derivatives were synthesized. → The structures were determined by IR, 1 H NMR, 13 C NMR and HRMS spectra. → We investigated the absorption and fluorescence spectral characteristics of the compounds. → The side group in 1,3,4-oxadiazole ring can affect its photophysical properties markedly. → Quantum calculation correlates well with their absorption.

Evaluation of a screening system for obesogenic compounds: screening of endocrine disrupting compounds and evaluation of the PPAR dependency of the effect.

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Anna Pereira-Fernandes

Full Text Available Recently the environmental obesogen hypothesis has been formulated, proposing a role for endocrine disrupting compounds (EDCs in the development of obesity. To evaluate this hypothesis, a screening system for obesogenic compounds is urgently needed. In this study, we suggest a standardised protocol for obesogen screening based on the 3T3-L1 cell line, a well-characterised adipogenesis model, and direct fluorescent measurement using Nile red lipid staining technique. In a first phase, we characterised the assay using the acknowledged obesogens rosiglitazone and tributyltin. Based on the obtained dose-response curves for these model compounds, a lipid accumulation threshold value was calculated to ensure the biological relevance and reliability of statistically significant effects. This threshold based method was combined with the well described strictly standardized mean difference (SSMD method for classification of non-, weak- or strong obesogenic compounds. In the next step, a range of EDCs, used in personal and household care products (parabens, musks, phthalates and alkylphenol compounds, were tested to further evaluate the obesogenicity screening assay for its discriminative power and sensitivity. Additionally, the peroxisome proliferator activated receptor γ (PPARγ dependency of the positive compounds was evaluated using PPARγ activation and antagonist experiments. Our results showed the adipogenic potential of all tested parabens, several musks and phthalate compounds and bisphenol A (BPA. PPARγ activation was associated with adipogenesis for parabens, phthalates and BPA, however not required for obesogenic effects induced by Tonalide, indicating the role of other obesogenic mechanisms for this compound.

Integrated HPTLC-based Methodology for the Tracing of Bioactive Compounds in Herbal Extracts Employing Multivariate Chemometrics. A Case Study on Morus alba.

Science.gov (United States)

Chaita, Eliza; Gikas, Evagelos; Aligiannis, Nektarios

2017-03-01

In drug discovery, bioassay-guided isolation is a well-established procedure, and still the basic approach for the discovery of natural products with desired biological properties. However, in these procedures, the most laborious and time-consuming step is the isolation of the bioactive constituents. A prior identification of the compounds that contribute to the demonstrated activity of the fractions would enable the selection of proper chromatographic techniques and lead to targeted isolation. The development of an integrated HPTLC-based methodology for the rapid tracing of the bioactive compounds during bioassay-guided processes, using multivariate statistics. Materials and Methods - The methanol extract of Morus alba was fractionated employing CPC. Subsequently, fractions were assayed for tyrosinase inhibition and analyzed with HPTLC. PLS-R algorithm was performed in order to correlate the analytical data with the biological response of the fractions and identify the compounds with the highest contribution. Two methodologies were developed for the generation of the dataset; one based on manual peak picking and the second based on chromatogram binning. Results and Discussion - Both methodologies afforded comparable results and were able to trace the bioactive constituents (e.g. oxyresveratrol, trans-dihydromorin, 2,4,3'-trihydroxydihydrostilbene). The suggested compounds were compared in terms of R f values and UV spectra with compounds isolated from M. alba using typical bioassay-guided process. Chemometric tools supported the development of a novel HPTLC-based methodology for the tracing of tyrosinase inhibitors in M. alba extract. All steps of the experimental procedure implemented techniques that afford essential key elements for application in high-throughput screening procedures for drug discovery purposes. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Thermoelectric and Structural Properties of Zr-/Hf-Based Half-Heusler Compounds Produced at a Large Scale

Science.gov (United States)

Zillmann, D.; Waag, A.; Peiner, E.; Feyand, M.-H.; Wolyniec, A.

2018-02-01

The half-Heusler (HH) systems are promising candidates for thermoelectric (TE) applications since they have shown high figures of merit ( zT) of ˜ 1, which are directly related to the energy conversion efficiency. To use HH compounds for TE devices, the materials must be phase-stable at operating temperatures up to 600°C. Currently, only a few HH compositions are available in large quantities. Hence, we focus on the TE and structural properties of three commercially available Zr-/Hf-based HH compounds in this publication. In particular, we evaluate the thermal conductivities and the figures of merit and critically discuss uncertainties and propagation error in the measurements. We find thermal conductivities of less than 6.0 W K^{-1}m^{-1} for all investigated materials and notably high figures of merit of 0.93 and 0.60 for n- and p-type compounds, respectively, at 600°C. Additionally, our investigations reveal that the grain structures of all materials also contain secondary phases like HfO2, Sn-Ni and Ti-Zr-Sn rich phases while an additional SnO_2 phase was found following several hours of harsh heat treatment at 800°C.

Liver function tests using the stable istope 15N

International Nuclear Information System (INIS)

Faust, H.; Jung, K.; Hirschberg, K.; Krumbiegel, P.; Junghans, P.; Reinhardt, R.; Teichmann, B.

1988-01-01

Several liver function tests using oral application of a nitrogen compound labelled with 15 N and the subsequent determination of 15 N in a certain fraction of urine or in the total urine by emission spectrometry are described. Because of the key function of the liver in the metabolism of nitrogen compounds, the results of these tests allow conclusions concerning some disturbances of liver functions. (author)

Structure-Based Drug Design of Novel Potent and Selective Tetrahydropyrazolo[1,5- a ]pyrazines as ATR Inhibitors

Energy Technology Data Exchange (ETDEWEB)

Barsanti, Paul A; Aversa, Robert J.; Jin, Xianming; Pan, Yue; Lu, Yipin; Elling, Robert; Jain, Rama; Knapp, Mark; Lan, Jiong; Lin, Xiaodong; Rudewicz, Patrick; Sim, Janet; Taricani, Lorena; Thomas, George; Xiao, Linda; Yue, Qin (Novartis)

2015-01-08

A saturation strategy focused on improving the selectivity and physicochemical properties of ATR inhibitor HTS hit 1 led to a novel series of highly potent and selective tetrahydropyrazolo[1,5-a]pyrazines. Use of PI3Kα mutants as ATR crystal structure surrogates was instrumental in providing cocrystal structures to guide the medicinal chemistry designs. Detailed DMPK studies involving cyanide and GSH as trapping agents during microsomal incubations, in addition to deuterium-labeled compounds as mechanistic probes uncovered the molecular basis for the observed CYP3A4 TDI in the series.

Identification of compounds with anti-proliferative activity against Trypanosoma brucei brucei strain 427 by a whole cell viability based HTS campaign.

Directory of Open Access Journals (Sweden)

Melissa L Sykes

Full Text Available Human African Trypanosomiasis (HAT is caused by two trypanosome sub-species, Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense. Drugs available for the treatment of HAT have significant issues related to difficult administration regimes and limited efficacy across species and disease stages. Hence, there is considerable need to find new alternative and less toxic drugs. An approach to identify starting points for new drug candidates is high throughput screening (HTS of large compound library collections. We describe the application of an Alamar Blue based, 384-well HTS assay to screen a library of 87,296 compounds against the related trypanosome subspecies, Trypanosoma brucei brucei bloodstream form lister 427. Primary hits identified against T.b. brucei were retested and the IC(50 value compounds were estimated for T.b. brucei and a mammalian cell line HEK293, to determine a selectivity index for each compound. The screening campaign identified 205 compounds with greater than 10 times selectivity against T.b. brucei. Cluster analysis of these compounds, taking into account chemical and structural properties required for drug-like compounds, afforded a panel of eight compounds for further biological analysis. These compounds had IC(50 values ranging from 0.22 µM to 4 µM with associated selectivity indices ranging from 19 to greater than 345. Further testing against T.b. rhodesiense led to the selection of 6 compounds from 5 new chemical classes with activity against the causative species of HAT, which can be considered potential candidates for HAT early drug discovery. Structure activity relationship (SAR mining revealed components of those hit compound structures that may be important for biological activity. Four of these compounds have undergone further testing to 1 determine whether they are cidal or static in vitro at the minimum inhibitory concentration (MIC, and 2 estimate the time to kill.

[Study on artificial compound feed for Buthus martensii].

Science.gov (United States)

Xu, Shi-Cai; Shen, Xue-Jian; Wang, Qiang; Han, Xiu-Kun

2014-03-01

To solve the problem that the single feed causing malnutrition, extension of the life cycle and low survival rates of Buthus martensii. By using Minitab (R) 15.1.1.0.0., 7 different kinds of compound feed were designed, including minced meat mud (pork,chicken and rabbit), bran (fried yellow), sugar, milk, vegetable paste and multivitamin as raw material. Different proportions of compound feed that taking the yellow mealworm as main component had a significant effect on the growth, mortality and birth number of Buthus martensii. Compound feed 5 significantly reduced mortality of youth scorpion. The compound feed 4 was the best in improving the weight of scorpion larvae and youth scorpion, and the farrowing number of mother scorpion. Other indicators were also good. Proportions in meatmud (pork, chicken and rabbit), bran (fried yellow), sugar, milk, vegetable paste and multivitamin was 30.00%, 25.00%, 20.08%, 15.58%, 8.08% and 1.25%, respectively. The growth of Buthus martensii is significantly influenced by the type of feed. In the production of compound feed, the yellow mealworm with compound feed 4 can be popularized.

Sensitivity of energy-packed compounds based on superfine and nanoporous silicon to pulsed electrical treatments

Energy Technology Data Exchange (ETDEWEB)

Zegrya, G. G. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Savenkov, G. G. [Saint-Petersburg State Engineering Institute (Technical University) (Russian Federation); Morozov, V. A. [Saint-Petersburg State University (Russian Federation); Zegrya, A. G.; Ulin, N. V., E-mail: Ulin@mail.ioffe.ru; Ulin, V. P. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Lukin, A. A. [Saint-Petersburg State Engineering Institute (Technical University) (Russian Federation); Bragin, V. A.; Oskin, I. A. [AO Scientific Production Association Poisk (Russian Federation); Mikhailov, Yu. M. [Russian Academy of Sciences, Institute of Problems of Chemical Physics (Russian Federation)

2017-04-15

The sensitivity of an energy-packed compound based on nanoporous silicon and calcium perchlorate to a high-current electron beam is studied. The initiation of explosive transformations in a mixture of potassium picrate with a highly dispersed powder of boron-doped silicon by means of a high-voltage discharge is examined. It is shown that explosive transformation modes (combustion and explosion) appear in the energy-packed compound under study upon its treatment with an electron beam. A relationship is established between the explosive transformation modes and the density of the energy-packed compound and between the breakdown (initiation) voltage and the mass fraction of the silicon powder.

Antifungal chemical compounds identified using a C. elegans pathogenicity assay.

Directory of Open Access Journals (Sweden)

Julia Breger

2007-02-01

Full Text Available There is an urgent need for the development of new antifungal agents. A facile in vivo model that evaluates libraries of chemical compounds could solve some of the main obstacles in current antifungal discovery. We show that Candida albicans, as well as other Candida species, are ingested by Caenorhabditis elegans and establish a persistent lethal infection in the C. elegans intestinal track. Importantly, key components of Candida pathogenesis in mammals, such as filament formation, are also involved in nematode killing. We devised a Candida-mediated C. elegans assay that allows high-throughput in vivo screening of chemical libraries for antifungal activities, while synchronously screening against toxic compounds. The assay is performed in liquid media using standard 96-well plate technology and allows the study of C. albicans in non-planktonic form. A screen of 1,266 compounds with known pharmaceutical activities identified 15 (approximately 1.2% that prolonged survival of C. albicans-infected nematodes and inhibited in vivo filamentation of C. albicans. Two compounds identified in the screen, caffeic acid phenethyl ester, a major active component of honeybee propolis, and the fluoroquinolone agent enoxacin exhibited antifungal activity in a murine model of candidiasis. The whole-animal C. elegans assay may help to study the molecular basis of C. albicans pathogenesis and identify antifungal compounds that most likely would not be identified by in vitro screens that target fungal growth. Compounds identified in the screen that affect the virulence of Candida in vivo can potentially be used as "probe compounds" and may have antifungal activity against other fungi.

HIV-1 pseudovirus neutralisation by a natural compound: a potential microbicide

CSIR Research Space (South Africa)

Van den Berg, N

2011-02-01

Full Text Available . The mode of action of the compound is, however, yet to be determined. The aim is to develop a microbicide based on an indigenous plant for people infected with HIV-1. The compound will also be screened against other HIV-1 subtypes to test the neutralisation...

Evaluation of different compound fertilizers for use in oil palm nursery

African Journals Online (AJOL)

The standard NPKMg 12:12:17:2 compound fertilizer (SF) for oil palm nurseries is not always available when needed. Evaluation of other compound fertilizers – NKP 15:15:15 and NPK 20:10:10 – compared with the SF were carried out in the main nursery at NIFOR to ascertain their suitability and rates of application.

Analyzing compound and project progress through multi-objective-based compound quality assessment.

Science.gov (United States)

Nissink, J Willem M; Degorce, Sébastien

2013-05-01

Compound-quality scoring methods designed to evaluate multiple drug properties concurrently are useful to analyze and prioritize output from drug-design efforts. However, formalized multiparameter optimization approaches are not widely used in drug design. We rank molecules synthesized in drug-discovery projects using simple and aggregated desirability functions reflecting medicinal chemistry 'rules'. Our quality score deals transparently with missing data, a key requirement in drug-hunting projects where data availability is often limited. We further estimate confidence in the interpretation of such a compound-quality measure. Scores and associated confidences provide systematic insight in the quality of emerging chemical equity. Tracking quality of synthetic output over time yields valuable insight into the progress of drug-design teams, with potential applications in risk and resource management of a drug portfolio.

Multi-class Mode of Action Classification of Toxic Compounds Using Logic Based Kernel Methods.

Science.gov (United States)

Lodhi, Huma; Muggleton, Stephen; Sternberg, Mike J E

2010-09-17

Toxicity prediction is essential for drug design and development of effective therapeutics. In this paper we present an in silico strategy, to identify the mode of action of toxic compounds, that is based on the use of a novel logic based kernel method. The technique uses support vector machines in conjunction with the kernels constructed from first order rules induced by an Inductive Logic Programming system. It constructs multi-class models by using a divide and conquer reduction strategy that splits multi-classes into binary groups and solves each individual problem recursively hence generating an underlying decision list structure. In order to evaluate the effectiveness of the approach for chemoinformatics problems like predictive toxicology, we apply it to toxicity classification in aquatic systems. The method is used to identify and classify 442 compounds with respect to the mode of action. The experimental results show that the technique successfully classifies toxic compounds and can be useful in assessing environmental risks. Experimental comparison of the performance of the proposed multi-class scheme with the standard multi-class Inductive Logic Programming algorithm and multi-class Support Vector Machine yields statistically significant results and demonstrates the potential power and benefits of the approach in identifying compounds of various toxic mechanisms. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Research of operational properties of compound based on high viscosity styrene-butadiene rubber SSBR-2560 TDAE HV

Directory of Open Access Journals (Sweden)

M. I. Falyakhov

2016-01-01

Full Text Available The article consider the influence of replacement of SSBR-2560 TDAE batch production on high viscosity SSBR-2560-TDAE HV in the tread recipe on the tire performance properties. Obtained samples were highly viscosity styrene butadiene rubber did not differ in the microstructure of the SSBR-2560 TDAE batch production. Increasing the molecular weight possible to increase the Mooney viscosity of the rubber, however, is known to one of adverse factors is the deterioration of processability of rubber compounds based on polymers. In this connection, investigated the behavior in the step mixing compound based on high viscosity SSBR rubber. We chose recipes tread of the tire with a high content of organic silicon filler. It is established that the equivalent replacement of the polymer in the tread recipe does not lead to significant changes in the basic parameters of rubber mixing. We observed a slight increase in the energy consumption for the preparation of the rubber compounds, as well as the discharge temperature at each stage. It was shown to improve the distribution of the filler in the polymer matrix for the compound based on SSBR-2560 TDAE HV. The results showed that compound based on high viscosity SSBR improves rolling resistance and traction characteristics, while maintaining abrasion in comparison with the SSBR-2560-M27 batch production. Recommended use this brand in the production of rubber car tires.

Phosphorus-containing macrocyclic compounds: synthesis and properties

International Nuclear Information System (INIS)

Knyazeva, I R; Burilov, Alexander R; Pudovik, Michael A; Habicher, Wolf D

2013-01-01

Main trends in the development of methods for the synthesis of phosphorus-containing macrocyclic compounds in the past 15 years are considered. Emphasis is given to reactions producing macrocyclic structures with the participation of a phosphorus atom and other functional groups involved in organophosphorus molecules and to modifications of macrocycles by phosphorus compounds in different valence states. Possibilities of the practical application of phosphorus-containing macrocyclic compounds in difference areas of science and engineering are discussed. The bibliography includes 205 references.

In search of new lead compounds for trypanosomiasis drug design: A protein structure-based linked-fragment approach

Science.gov (United States)

Verlinde, Christophe L. M. J.; Rudenko, Gabrielle; Hol, Wim G. J.

1992-04-01

A modular method for pursuing structure-based inhibitor design in the framework of a design cycle is presented. The approach entails four stages: (1) a design pathway is defined in the three-dimensional structure of a target protein; (2) this pathway is divided into subregions; (3) complementary building blocks, also called fragments, are designed in each subregion; complementarity is defined in terms of shape, hydrophobicity, hydrogen bond properties and electrostatics; and (4) fragments from different subregions are linked into potential lead compounds. Stages (3) and (4) are qualitatively guided by force-field calculations. In addition, the designed fragments serve as entries for retrieving existing compounds from chemical databases. This linked-fragment approach has been applied in the design of potentially selective inhibitors of triosephosphate isomerase from Trypanosoma brucei, the causative agent of sleeping sickness.

Isolaurenidificin and Bromlaurenidificin, Two New C15-Acetogenins from the Red Alga Laurencia obtusa

Directory of Open Access Journals (Sweden)

Nahed O. Bawakid

2017-05-01

Full Text Available Chromatographic fractionation of the CH2Cl2/MeOH extract of the Red Sea red alga Laurencia obtusa gave two new hexahydrofuro[3,2-b]furan-based C15-acetogenins, namely, isolaurenidificin (1 and bromlaurenidificin (2. The chemical structures were elucidated based on extensive analyses of their spectral data. Compounds 1 and 2 showed no toxicity (LC50 > 12 mM using Artemia salina as test organism. Both compounds showed weak cytotoxicity against A549, HepG-2, HCT116, MCF-7, and PC-3 cells, however, they exhibited a relatively potent cytotoxic activity against peripheral blood neutrophils. This can be attributed partly to induction of apoptosis.

Synthesis of 5-Substituted 3-Amino-1H-Pyrazole-4-Carbonitriles as Precursors for Microwave Assisted Regiospecific Syntheses of Pyrazolo[1,5-a]Pyrimidines

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Fawzia Al-Qalaf

2008-12-01

Full Text Available A simple route to 3-oxoalkanonitrile 5, aprecursor of the title compounds is described. Reaction of enaminones 2 with hydroxylamine hydrochloride in ethanol yielded aldoximes 3 that were converted readily into 5 in basic medium. This method has been successfully applied with a number of substrates and resulted in excellent yields of the products. Reacting 5 with trichloroacetonitrile afforded 3-amino-2-aroyl-4,4,4-trichloro-2-butenenitriles 6 that condensed with hydrazines to yield 3-amino-1H-pyrazole-4-carbonitrilederivatives 8. Substituted pyrazolo[1,5-a]pyridmidines have been prepared with regioselective condensation reactions of 8 with nonsymmetrical dielectrophiles. The structures of compounds obtained were deduced based on 1H-NMR, 1H-15N HMBC- measurements.

Efficient fluorescent deep-blue and hybrid white emitting devices based on carbazole/benzimidazole compound

KAUST Repository

Yang, Xiaohui; Zheng, Shijun; Bottger, Rebecca; Chae, HyunSik; Tanaka, Takeshi; Li, Sheng; Mochizuki, Amane; Jabbour, Ghassan E.

2011-01-01

We report the synthesis, photophysics, and electrochemical characterization of carbazole/benzimidazole-based compound (Cz-2pbb) and efficient fluorescent deep-blue light emitting devices based on Cz-2pbb with the peak external quantum efficiency

Elastic constants of a Laves phase compound: C15 NbCr2

International Nuclear Information System (INIS)

Ormeci, A.; Chu, F.; Wills, J.M.; Chen, S.P.; Albers, R.C.; Thoma, D.J.; Mitchell, T.E.

1997-01-01

The single-crystal elastic constants of C15 NbCr 2 have been computed by using a first-principles, self-consistent, full-potential total energy method. From these single-crystal elastic constants the isotropic elastic moduli are calculated using the Voigt and Reuss averages. The calculated values are in fair agreement with the experimental values. The implications of the results are discussed with regards to Poisson's ratio and the direction dependence of Young's modulus

Stable isotope sup 15 N-urea and clinical research in nephrology

Energy Technology Data Exchange (ETDEWEB)

Sugino, Nobuhiro; Arai, Junko; Akimoto, Mitsuko; Miwa, Toichiro; Takuma, Takehide (Tokyo Women' s Medical Coll. (Japan))

1990-08-01

Stable isotope {sup 15}N-compound, {sup 15}N-urea, is useful marker to investigate nitrogen metabolism in clinical nephrology, particularly in chronic renal failure or dialysis. {sup 15}N-urea incorporation into plasma albumin in addition to plasma {sup 15}N disappearance was studied in 6 patients with endstage chronic renal failure. As a result, only minor fraction of administered {sup 15}N-urea was incorporated into albumin in this study. In addition, it was also confirmed that high energy diet may promote protein synthesis through {sup 15}N incorporation to plasma amino acids, such as alanine, in these patients with low protein meal. Therefore, administration of {sup 15}N-compound to human subjects may contribute to provide us the important informations on nitrogen metabolism. For instance, urea kinetics are described in the endstage chronic renal failure in this review. However, less expensive {sup 15}N-compounds should be provided and more simple but accurate measurement of {sup 15}N activity should be developed for the further clinical application of the stable isotope. (author).

Study of reticular defects in V3Si (A15 structure)

International Nuclear Information System (INIS)

Ben Lamine, Abdelmottaleb

1980-01-01

The A15 crystal structure is that of superconductive compounds with high critical temperature. This research thesis aims at studying its possible reticular defects. In a first part, the author presents this structure and more particularly its crystallographic properties, reports the indexing of electronic diffraction diagrams (point diagrams and line diagrams of Kikuchi) in the case of V 3 Si. Then, after having described the sample preparation technique, the author reports the study of reticular defects by high voltage electronic microscopy on a raw V 3 Si crystal. The existence of a specific defect is highlighted and the crystallographic study of this defect is reported. It has been performed by means of computer-based simulation of contrast (TWODIS software). Results are then discussed

Effective anti-leishmanial activity of minimalist squaramide-based compounds.

Science.gov (United States)

Marín, Clotilde; Ximenis, Marta; Ramirez-Macías, Inmaculada; Rotger, Carmen; Urbanova, Kristina; Olmo, Francisco; Martín-Escolano, Rubén; Rosales, María José; Cañas, Rocio; Gutierrez-Sánchez, Ramón; Costa, Antonio; Sánchez-Moreno, Manuel

2016-11-01

In order to evaluate the in vitro leishmanicidal activity of N,N'-Squaramides derivatives, compounds that feature both hydrogen bond donor and acceptor groups and are capable of multiple interactions with complementary sites, against Leishmania infantum, Leishmania braziliensis and Leishmania donovani a series of 18compounds was prepared and assayed on extracellular and intracellular parasite forms. Infectivity and cytotoxicity tests were performed on J774.2 macrophage cells using meglumine antimoniate (Glucantime) as the reference drug. Changes in metabolite excretion by 1 H-NMR and the ultrastructural alterations occurring in the parasites treated using transmission electron microscopy (TEM), was analyzed. Compounds 1, 7, 11, 14 and 17 were the more active and less toxic. Infection rates showed that the order of effectiveness was 17 > 11 > 14 > 7 for both L. infantum and L. braziliensis and in the same way, the compound 1 for L. donovani. All these compounds have altered the typical structure of the promastigotes, glycosomes and mitochondria. These severe modifications by the compounds are the ultimate reasons for the alterations observed in the excretion products. The Squaramide 17 (3-(butylamino)-4-((3-(dimetilamino)propyl)(methyl)amino)cyclobut-3-en-1,2-dione) was clearly the most efficient of all compounds. The data appear to confirm that the severe modifications generated in organelles such as glycosomes or mitochondria by the compounds are the ultimate reasons for the alterations observed in the excretion products of all species. The activity, stability, low cost of starting materials, and straightforward synthesis make amino squaramides appropriate molecules for the development of an affordable anti-leishmanial agent. Copyright © 2016. Published by Elsevier Inc.

Chemopreventive evaluation of a Schiff base derived copper (II) complex against azoxymethane-induced colorectal cancer in rats.

Science.gov (United States)

Hajrezaie, Maryam; Hassandarvish, Pouya; Moghadamtousi, Soheil Zorofchian; Gwaram, Nura Suleiman; Golbabapour, Shahram; Najihussien, Abdrabuh; Almagrami, Amel Abdullah; Zahedifard, Maryam; Rouhollahi, Elham; Karimian, Hamed; Fani, Somaye; Kamalidehghan, Behnam; Majid, Nazia Abdul; Ali, Hapipah Mohd; Abdulla, Mahmood Ameen

2014-01-01

Based on the potential of Schiff base compounds to act as sources for the development of cancer chemotherapeutic agents, this in vivo study was performed to investigate the inhibitory properties of the synthetic Schiff base compound Cu(BrHAP)2 on colonic aberrant crypt foci (ACF). This study involved five groups of male rats. The negative control group was injected with normal saline once a week for 2 weeks and fed 10% Tween 20 for 10 weeks, the cancer control group was subcutaneously injected with 15 mg/kg azoxymethane once per week for two consecutive weeks, the positive control group was injected with 15 mg/kg azoxymethane once per week for two consecutive weeks and 35 mg/kg 5-fluorouracil (injected intra-peritoneally) for 4 weeks, and the experimental groups were first injected with 15 mg/kg azoxymethane once per week for two consecutive weeks and then fed 2.5 or 5 mg/kg of the Schiff base compound once a day for 10 weeks. Application of the Schiff base compound suppressed total colonic ACF formation by up to 72% to 74% (P<0.05) when compared with the cancer control group. Analysis of colorectal specimens revealed that treatments with the Schiff base compound decreased the mean crypt scores in azoxymethane-treated rats. Significant elevations of superoxide dismutase, glutathione peroxidase and catalase activities and a reduction in the level of malondialdehyde were also observed. Histologically, all treatment groups exhibited significant decreases in dysplasia compared to the cancer control group (P<0.05). Immunohistochemical staining demonstrated down-regulation of the PCNA protein. Comparative western blot analysis revealed that COX-2 and Bcl2 were up-regulated and Bax was down-regulated compared with the AOM control group. The current study demonstrated that the Cu(BrHAP)2 compound has promising chemoprotective activities that are evidenced by significant decreases in the numbers of ACFs in azoxymethane-induced colon cancer.

Chord length distribution for a compound capsule

International Nuclear Information System (INIS)

Pitřík, Pavel

2017-01-01

Chord length distribution is a factor important in the calculation of ionisation chamber responses. This article describes Monte Carlo calculations of the chord length distribution for a non-convex compound capsule. A Monte Carlo code was set up for generation of random chords and calculation of their lengths based on the input number of generations and cavity dimensions. The code was written in JavaScript and can be executed in the majority of HTML viewers. The plot of occurrence of cords of different lengths has 3 peaks. It was found that the compound capsule cavity cannot be simply replaced with a spherical cavity of a triangular design. Furthermore, the compound capsule cavity is directionally dependent, which must be taken into account in calculations involving non-isotropic fields of primary particles in the beam, unless equilibrium of the secondary charged particles is attained. (orig.)

Magnetic and transport properties of Ce 6MnSb 15

Science.gov (United States)

Godart, Claude; Rogl, Peter; Alleno, Eric; Gonçalves, António P.; Rouleau, Olivier

2006-05-01

In our effort to look for new Ce/Yb-based compounds with large unit cell, we studied Ce 6MnSb 15. Rietveld refinements of X-ray powder diffraction confirm that the material crystallizes in orthorhombic structure La 6MnSb 15-type, Imm2 space group, with 2 Ce sites (8e and 4d) and lattice parameters a=15.1643 Å, b=19.3875 Å and c=4.2794 Å, which closely agree with those already published. Magnetic susceptibility results show a paramagnetic behavior and no magnetic order down to 2 K in contrast to antiferromagnetic order previously reported at 7 K. Resistivity shows a metallic behavior and the Seebeck coefficient is very low, typically -2 μV/K.

Spin-canting magnetization in an unusual Co4 cluster-based layer compound from a 2,3-dihydroxyquinoxaline ligand.

Science.gov (United States)

Yang, Chen-I; Chuang, Po-Hsiang; Lee, Gene-Hsiang; Peng, Shie-Ming; Lu, Kuang-Lieh

2012-01-16

The self-assembly of Co(O(2)CPh)(2) with a 2,3-dihydroxyquinoxaline (H(2)dhq) linker has revealed a new two-dimensional cluster-based compound, [Co(4)(OMe)(2)(O(2)CPh)(2)(dhq)(2)(MeOH)(2)](n), which shows spin-canted magnetization and a definite magnetic hysteresis loop.

Microstructural characterization of a rapidly solidified ultrahigh strength Al94.5Cr3Co1.5Ce1 alloy

International Nuclear Information System (INIS)

Ping, D.H.; Hono, K.; Inoue, A.

2000-01-01

The microstructure of a rapidly solidified Al 94.5 Cr 3 Co 1.5 Ce 1 alloy has been examined in detail by means of high resolution transmission electron microscopy (HRTEM) and atom probe field ion microscopy (APFIM). In the as-quenched microstructure, nanoscale particles of a solute-enriched amorphous phase and an Al-Cr compound are dispersed in randomly oriented fine grains of α-Al ( 200nm ). The interface between the Al grains and the amorphous particles is not smooth but irregular with atomic protrusions and concavities, suggesting that interfacial instability occurs during the solidification process. Nanoscale amorphous particles are formed as a result of solute trapping within the rapidly grown Al grains. After annealing at 400 C for 15 minutes grain growth occurs, and the interface of the Al grains is smoothed. The amorphous region trapped within the grains if crystallized to an Al-Cr compound, but no icosahedral phase has been confirmed. The APFIM results have revealed that Cr and Ce atoms have a similar partitioning behavior, i.e., they are rejected from the α-Al phase and partitioned into the trapped amorphous regions. On the other hand, Co atoms are not partitioned between the two phases in the as-quenched state but are partitioned into the α-Al grains in the annealed alloys being rejected from the Al compounds and finally form Al-Co compounds. Based on these microstructural characterization results, the origins of high strength of this alloy are discussed

Six-membered ring aliphatic compounds: A search for regularities in phase transitions

International Nuclear Information System (INIS)

Nagrimanov, Ruslan N.; Solomonov, Boris N.; Emel’yanenko, Vladimir N.; Verevkin, Sergey P.

2016-01-01

Highlights: • Thermodynamics of sublimation and solution of halogen adamantanes is studied. • Sublimation enthalpies derived from transpiration and solution calorimetry in agreement. • Enthalpies of fusion measured by DSC and used to derive vaporization enthalpies. • Structure-property analysis of vaporization enthalpies was performed. - Abstract: Absolute vapor pressures of 1-Cl-adamantane, 2-Cl-adamantane, 1-Br-adamantane, 2-Br-adamantane, as well as of Br-cyclohexane were measured by using the transpiration method. Standard molar enthalpies of sublimation of halogen substituted adamantanes at 298.15 K were derived from vapor pressure temperature dependences. Standard molar enthalpies of solution of adamantane and halogen adamantanes in cyclohexane were measured with a high-precision solution calorimeter. A theoretical procedure based on the solution calorimetry was applied to derive sublimation enthalpies of halogen adamantanes independently. Molar enthalpies of fusion were measured with help of DSC. The consistent data set of phase transitions for each compound was evaluated and used for discussion of structure-property relations in adamantane and cyclohexane derivatives. A simple way to predict enthalpies of vaporization of compounds containing six-membered rings was suggested for practical thermochemical calculations.

Development of fluorescence imaging-based assay for screening cardioprotective compounds from medicinal plants.

Science.gov (United States)

Wang, Yi; Zhao, Xiaoping; Gao, Xiumei; Nie, Xiaojing; Yang, Yingxin; Fan, Xiaohui

2011-09-19

Medicinal plants have been widely recognized as a renewable resource for the discovery of novel leads and drug. In this study, an approach for screening and identification compounds with cardioprotective activity from medicinal plant extracts by cellular-fluorescence imaging technique was developed. It is a cell-based assay for measuring mitochondrial membrane potential changes in H9c2 cardiac muscle cells exposed to H(2)O(2) by using a fluorescence automatic microscopy screening platform. Rhodamine 123 was used as the fluorescent dye to indicate the change of mitochondrial membrane potential. The sensitivity and linear range of the proposed approach were evaluated and validated using vitamin C, an antioxidative compound. The method was applied to screen active components with potent cardioprotective effects from a traditional Chinese formula. The potential cardioprotective components were identified by liquid chromatography coupled with mass spectrometry (LC/MS). Moreover, the utility of the proposed approach was further validated by three compounds (salvianolic acid B, protocatechuic aldehyde, and tanshinone II A) identified from the formula which showed cardioprotective effects in a dose-dependent manner. These applications suggested that the proposed rapid and sensitive screening approach offers an efficient way to discover active components or compounds from medicinal plants. Copyright © 2011 Elsevier B.V. All rights reserved.

Synthesis of new heterocyclic compounds based on pyrazolopyridine scaffold and evaluation of their neuroprotective potential in MPP+-induced neurodegeneration.

Science.gov (United States)

Jouha, Jabrane; Loubidi, Mohammed; Bouali, Jamila; Hamri, Salha; Hafid, Abderrafia; Suzenet, Franck; Guillaumet, Gérald; Dagcı, Taner; Khouili, Mostafa; Aydın, Fadime; Saso, Luciano; Armagan, Güliz

2017-03-31

Neurodegenerative disorders including Alzheimer's disease, Parkinson's disease, and Huntington's disease affect millions of people in the world. Thus several new approaches to treat brain disorders are under development. The aim of the present study is to synthesize potential neuroprotective heterocyclic compounds based on pyrazolopyridine derivatives and then to evaluate their effects in MPP + -induced neurodegeneration in human neuroblastoma cell line (SH-SY5Y cells). The effects of the compounds on cell viability were measured by MTT assay and the changes in apoptosis-related proteins including bax, Bcl-2, Bcl-xl and caspase-3 were investigated by western blot technique. Based on the cell viability results obtained by MTT assay, the percentage of neuroprotection-induced by compounds against MPP + -induced neurotoxicity in SH-SY5Y cells was between 20% and 30% at 5 μM concentrations of all synthesized compounds. Moreover, the downregulation in pro-apoptotic proteins including bax and caspase-3 were found following the novel synthesized compounds treatments and these effects were observed in a dose-dependent manner. Our results provide an evidence that these heterocyclic compounds based on pyrazolopyridine derivatives may have a role on dopaminergic neuroprotection via antiapoptotic pathways. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Liver function tests using the stable isotope /sup 15/N

Energy Technology Data Exchange (ETDEWEB)

Faust, H; Jung, K; Hirschberg, K; Krumbiegel, P; Junghans, P; Reinhardt, R; Matkowitz, R; Teichmann, B

1988-01-01

Several liver function tests using oral application of a nitrogen compound labelled with /sup 15/N and the subsequent determination of /sup 15/N in a certain fraction of urine or in the total urine by emission spectrometry are described. Because of the key function of the liver in the metabolism of nitrogen compounds, the results of these tests allow conclusions concerning some disturbances of liver functions.

The use of compound topical anesthetics: a review.

Science.gov (United States)

Kravitz, Neal D

2007-10-01

The author reviewed the history of, federal regulations regarding, risks of and adverse drug reactions of five compound topical anesthetics: tetracaine, adrenaline/epinephrine and cocaine (TAC); lidocaine, adrenaline/epinephrine and tetracaine (LET); lidocaine, tetracaine and phenylephrine (TAC 20 percent Alternate); lidocaine, prilocaine and tetracaine (Profound); and lidocaine, prilocaine, tetracaine and phenylephrine with thickeners (Profound PET). The author reviewed clinical trials, case reports, descriptive articles, and U.S. Food and Drug Administration (FDA) regulations and recent public advisory warnings regarding the federal approval of and risks associated with the use of compound topical anesthetics. Compound topical anesthetics are neither FDA-regulated nor -unregulated. Some compounding pharmacies bypass the new FDA drug approval process, which is based on reliable scientific data and ensures that a marketed drug is safe, effective, properly manufactured and accurately labeled. Two deaths have been attributed to the lay use of compound topical anesthetics. In response, the FDA has announced the strengthening of its efforts against unapproved drug products. Compound topical anesthetics may be an effective alternative to local infiltration for some minimally invasive dental procedures; however, legitimate concerns exist in regard to their safety. Until they become federally regulated, compound topical anesthetics remain unapproved drug products whose benefits may not outweigh their risks for dental patients.

Identification of a New Antibacterial Sulfur Compound from Raphanus sativus Seeds

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Jeries Jadoun

2016-01-01

Full Text Available Raphanus sativus L. (radish, a member of Brassicaceae, is widely used in traditional medicine in various cultures for treatment of several diseases and disorders associated with microbial infections. The antibacterial activity of the different plant parts has been mainly attributed to several isothiocyanate (ITC compounds. However, the low correlation between the ITC content and antibacterial activity suggests the involvement of other unknown compounds. The objective of this study was to investigate the antibacterial potential of red radish seeds and identify the active compounds. A crude ethanol seed extract was prepared and its antibacterial activity was tested against five medically important bacteria. The ethanol extract significantly inhibited the growth of all tested strains. However, the inhibitory effect was more pronounced against Streptococcus pyogenes and Escherichia coli. Bioassay-guided fractionation of the ethanol extract followed by HPLC, 1H-NMR, 13C-NMR, 15N-NMR, and HMBC analysis revealed that the active fraction consisted of a single new compound identified as [5-methylsulfinyl-1-(4-methylsulfinyl-but-3-enyl-pent-4-enylidene]-sulfamic acid, which consisted of two identical sulfur side chains similar to those found in ITCs. The minimal inhibitory concentration values of the isolated compound were in the range of 0.5–1 mg/mL. These results further highlight the role of radish as a rich source of antibacterial compounds.

A method of detecting carbonyl compounds in tree leaves in China.

Science.gov (United States)

Huang, Juan; Feng, Yanli; Fu, Jiamo; Sheng, Guoying

2010-06-01

Carbonyl compounds have been paid more and more attention because some carbonyl species have been proven to be carcinogenic or a risk for human health. Plant leaves are both an important emission source and an important sink of carbonyl compounds. But the research on carbonyl compounds from plant leaves is very scarce. In order to make an approach to the emission mechanism of plant leaves, a new method was established to extract carbonyl compounds from fresh plant leaves. The procedure combining derivatization with ultrasonication was developed for the fast extraction of carbonyl compounds from tree leaves. Fresh leaves (Metasequoia glyptostroboides), were selected and extracted by this method. Seven carbonyl compounds, including formaldehyde, acetaldehyde, acetone, acrolein, p-tolualdehyde, m/o-tolualdehyde, and hexaldehyde were determined and quantified. The most common carbonyl species of the four tree leaves were formaldehyde, acrolein, and m/o-tolualdehyde. They accounted for 67.3% in cedar, 50.8% in sweet olive, 45.8% in dawn redwood, and 44.6% in camphor tree, respectively. Camphor tree had the highest leaf level of m/o-tolualdehyde with 15.0 +/- 3.4 microg g(-1)(fresh leaf weight), which indicated that camphor tree may be a bioindicator of the level of tolualdehyde or xylene in the atmosphere. By analyzing carbonyl compounds from different tree leaves, it is not only helpful for further studying the relationship between sink and emission of carbonyls from plants, but also helpful for exploring optimum plant population in urban greening.

Forecasting of superconducting compounds

International Nuclear Information System (INIS)

Savitskii, E.M.; Gribulya, V.G.; Kiseleva, N.N.

1981-01-01

In forecasting new superconducting intermetallic compounds of the A15 and Mo 3 Se types most promising from the viewpoint of high critical temperature Tsub(c), high critical magnetic fields Hsub(c), and high critical currents and in estimating their transition temperature it is proposed to apply cybernetic methods of computer learning

Sources and transformation of dissolved and particulate organic nitrogen in the North Pacific Subtropical Gyre indicated by compound-specific δ15N analysis of amino acids

Science.gov (United States)

Yamaguchi, Yasuhiko T.; McCarthy, Matthew D.

2018-01-01

This study explores the use of compound-specific nitrogen isotopes of amino acids (δ15NAA) of coupled dissolved and particulate organic nitrogen (DON, PON) samples as a new approach to examine relative sources, transformation processes, and the potential coupling of these two major forms of N cycle in the ocean water column. We measured δ15NAA distributions in high-molecular-weight dissolved organic nitrogen (HMW DON) and suspended PON in the North Pacific Subtropical Gyre (NPSG) from surface to mesopelagic depths. A new analytical approach achieved far greater δ15NAA measurement precision for DON than earlier work, allowing us to resolve previously obscured differences in δ15NAA signatures, both with depth and between ON pools. We propose that δ15N values of total hydrolysable amino acids (THAA) represents a proxy for proteinaceous ON δ15N values in DON and PON. Together with bulk δ15N values, this allows δ15N values and changes in bulk, proteinaceous, and ;other-N; to be directly evaluated. These novel measurements suggest three main conclusions. First, the δ15NAA signatures of both surface and mesopelagic HMW DON suggest mainly heterotrophic bacterial sources, with mesopelagic HMW DON bearing signatures of far more degraded material compared to surface material. These results contrast with a previous proposal that HMW DON δ15NAA patterns are essentially ;pre-formed; by cyanobacteria in the surface ocean, undergo little change with depth. Second, different δ15NAA values and patterns of HMW DON vs. suspended PON in the surface NPSG suggest that sources and cycling of these two N reservoirs are surpisingly decoupled. Based on molecular δ15N signatures, we propose a new hypothesis that production of surface HMW DON is ultimately derived from subsurface nitrate, while PON in the mixed layer is strongly linked to N2 fixation and N recycling. In contrast, the comparative δ15NAA signatures of HMW DON vs. suspended PON in the mesopelagic also suggest a

4-Phenethylthio-2-phenylpyrazolo[1,5-a][1,3,5]triazin-7(6H-one

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Sergey A. Smolnikov

2017-12-01

Full Text Available Exploring the pharmacologically important pyrazolo[1,5-a][1,3,5]triazin-7(6H-one scaffold for the construction of new bioactive compounds, we developed a synthesis of 4-phenethylthio-2-phenylpyrazolo[1,5-a][1,3,5]triazin-7(6H-one (4 via S-alkylation of 2-phenyl-4-thioxopyrazolo[1,5-a][1,3,5]triazine-7(6H-one (3, prepared by the double ring closure of pyrazole and triazine rings upon the treatment of 1-cyanoacetyl-4-benzoylthiosemicarbazide (2 with alkali. The antiproliferative activity of 4 against human lung cancer (A549 and human breast cancer (MDA-MB231 cell lines was investigated. Compound 4 was found to be more active against lung cancer cells than breast cancer cells.

Solid phase microextraction and stir bar sorptive extraction for organotin compounds - a comparison (P9)

International Nuclear Information System (INIS)

Mothes, S.; Wennrich, R.

2002-01-01

Full text: Organotin compounds have been largely used in agricultural and industrial applications. Hyphenated techniques were developed for the sensitive and selective determination of such species. For this task GC has been coupled with atomic emission detection. Derivatization to transform the Sn-compounds into sufficiently volatile compounds was necessary and carried out using sodium tetrapropylborate. For sample preparation the application of solid phase microextraction (SPME) give recent advances in comparison to classical liquid-liquid extraction (LEE). A problem in the usage of SPME exists however in the small volume of the PDMS coating for enrichment the analytes. For improvement of both sample enrichment and extraction of the organotin compounds stir bar sorptive extraction (SBSE) was applied. It base on the application of stir bars coated with PDMS. Here the extraction yield is substantially higher. Aim of this study was to compare the capabilities of GC-AED in combination with SPME and SBSE. After optimization of the experimental parameters it was possible to reach detection limits in the pg / 1 - level. A comparison of both methods shows the expected results. By application of SBSE it was possible to increase the detection limits one order of magnitude. With SPME the reproducibility of the analytical results (in the 1 ng / 1 concentration range) was found to be between 10 and 15 %, it could be enhanced to 5-8 % by application of SBSE. These low limits of detection and the good reproducibility allowed the determination of organotin compounds according required regulations. Ref. 1 (author)

Screening for Antifibrotic Compounds Using High Throughput System Based on Fluorescence Polarization

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Branko Stefanovic

2014-04-01

Full Text Available Fibroproliferative diseases are one of the leading causes of death worldwide. They are characterized by reactive fibrosis caused by uncontrolled synthesis of type I collagen. There is no cure for fibrosis and development of therapeutics that can inhibit collagen synthesis is urgently needed. Collagen α1(I mRNA and α2(I mRNA encode for type I collagen and they have a unique 5' stem-loop structure in their 5' untranslated regions (5'SL. Collagen 5'SL binds protein LARP6 with high affinity and specificity. The interaction between LARP6 and the 5'SL is critical for biosynthesis of type I collagen and development of fibrosis in vivo. Therefore, this interaction represents is an ideal target to develop antifibrotic drugs. A high throughput system to screen for chemical compounds that can dissociate LARP6 from 5'SL has been developed. It is based on fluorescence polarization and can be adapted to screen for inhibitors of other protein-RNA interactions. Screening of 50,000 chemical compounds yielded a lead compound that can inhibit type I collagen synthesis at nanomolar concentrations. The development, characteristics, and critical appraisal of this assay are presented.

Speciated measurements of semivolatile and intermediate volatility organic compounds (S/IVOCs in a pine forest during BEACHON-RoMBAS 2011

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A. W. H. Chan

2016-02-01

Full Text Available Understanding organic composition of gases and particles is essential to identifying sources and atmospheric processing leading to organic aerosols (OA, but atmospheric chemical complexity and the analytical techniques available often limit such analysis. Here we present speciated measurements of semivolatile and intermediate volatility organic compounds (S/IVOCs using a novel dual-use instrument (SV-TAG-AMS deployed at Manitou Forest, CO, during the Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen – Rocky Mountain Biogenic Aerosol Study (BEACHON-RoMBAS 2011 campaign. This instrument provides on-line speciation of ambient organic compounds with 2 h time resolution. The species in this volatility range are complex in composition, but their chemical identities reveal potential sources. Observed compounds of biogenic origin include sesquiterpenes with molecular formula C15H24 (e.g., β-caryophyllene and longifolene, which were most abundant at night. A variety of other biogenic compounds were observed, including sesquiterpenoids with molecular formula C15H22, abietatriene and other terpenoid compounds. Many of these compounds have been identified in essential oils and branch enclosure studies but were observed in ambient air for the first time in our study. Semivolatile polycyclic aromatic hydrocarbons (PAHs and alkanes were observed with highest concentrations during the day and the dependence on temperature suggests the role of an evaporative source. Using statistical analysis by positive matrix factorization (PMF, we classify observed S/IVOCs by their likely sources and processes, and characterize them based on chemical composition. The total mass concentration of elutable S/IVOCs was estimated to be on the order of 0.7 µg m−3 and their volatility distributions are estimated for modeling aerosol formation chemistry.

Optimization of the solvent-based dissolution method to sample volatile organic compound vapors for compound-specific isotope analysis.

Science.gov (United States)

Bouchard, Daniel; Wanner, Philipp; Luo, Hong; McLoughlin, Patrick W; Henderson, James K; Pirkle, Robert J; Hunkeler, Daniel

2017-10-20

The methodology of the solvent-based dissolution method used to sample gas phase volatile organic compounds (VOC) for compound-specific isotope analysis (CSIA) was optimized to lower the method detection limits for TCE and benzene. The sampling methodology previously evaluated by [1] consists in pulling the air through a solvent to dissolve and accumulate the gaseous VOC. After the sampling process, the solvent can then be treated similarly as groundwater samples to perform routine CSIA by diluting an aliquot of the solvent into water to reach the required concentration of the targeted contaminant. Among solvents tested, tetraethylene glycol dimethyl ether (TGDE) showed the best aptitude for the method. TGDE has a great affinity with TCE and benzene, hence efficiently dissolving the compounds during their transition through the solvent. The method detection limit for TCE (5±1μg/m 3 ) and benzene (1.7±0.5μg/m 3 ) is lower when using TGDE compared to methanol, which was previously used (385μg/m 3 for TCE and 130μg/m 3 for benzene) [2]. The method detection limit refers to the minimal gas phase concentration in ambient air required to load sufficient VOC mass into TGDE to perform δ 13 C analysis. Due to a different analytical procedure, the method detection limit associated with δ 37 Cl analysis was found to be 156±6μg/m 3 for TCE. Furthermore, the experimental results validated the relationship between the gas phase TCE and the progressive accumulation of dissolved TCE in the solvent during the sampling process. Accordingly, based on the air-solvent partitioning coefficient, the sampling methodology (e.g. sampling rate, sampling duration, amount of solvent) and the final TCE concentration in the solvent, the concentration of TCE in the gas phase prevailing during the sampling event can be determined. Moreover, the possibility to analyse for TCE concentration in the solvent after sampling (or other targeted VOCs) allows the field deployment of the sampling

Leaching characteristics of calcium-based compounds in MSWI Residues: From the viewpoint of clogging risk.

Science.gov (United States)

Xia, Yi; Zhang, Hua; Phoungthong, Khamphe; Shi, Dong-Xiao; Shen, Wen-Hui; Shao, Li-Ming; He, Pin-Jing

2015-08-01

Leachate collection system (LCS) clogging caused by calcium precipitation would be disadvantageous to landfill stability and operation. Meanwhile, calcium-based compounds are the main constituents in both municipal solid waste incineration bottom ash (MSWIBA) and stabilized air pollution control residues (SAPCR), which would increase the risk of LCS clogging once these calcium-rich residues were disposed in landfills. The leaching behaviors of calcium from the four compounds and municipal solid waste incineration (MSWI) residues were studied, and the influencing factors on leaching were discussed. The results showed that pH was the crucial factor in the calcium leaching process. CaCO3 and CaSiO3 began leaching when the leachate pH decreased to less than 7 and 10, respectively, while Ca3(PO4)2 leached at pHleaching rate for the different calcium-based compounds is as follows: CaSiO3>Ca3(PO4)2>CaCO3. The calcium leaching from the MSWIBA and SAPCR separately started from pHleaching respectively, which was proven by the X-ray diffraction results. Based on the leaching characteristics of the different calcium compounds and the mineral phase of calcium in the incineration residues, simulated computation of their clogging potential was conducted, providing the theoretical basis for the risk assessment pertaining to LCS clogging in landfills. Copyright © 2015 Elsevier Ltd. All rights reserved.

Solid-phase extraction element based on epoxy polymer monolith for determination of polar organic compounds in aqueous media.

Science.gov (United States)

Takahashi, Tadashi; Odagiri, Kayo; Watanabe, Atsushi; Watanabe, Chuichi; Kubo, Takuya; Hosoya, Ken

2011-10-01

A solid-phase extraction element based on epoxy polymer monolith was fabricated for sorptive enrichment of polar compounds from liquid and gaseous samples. After ultrasonication of the element in an aqueous solution for a given period of time, the thermal desorption (TD) using a pyrolyzer with gas chromatography/mass spectrometry (GC/MS), in which TD temperature was programmed from 50 to 250 °C for the analytes absorbed in the element, was used to evaluate the element for basic extraction performance using the aqueous standard mixtures consisting of compounds having varied polarities such as hexanol, isoamyl acetate, linalool, furfural and decanoic acid, in concentrations ranging from 10 μg/L to 1 mg/L. Excellent linear relationships were observed for all compounds in the standard mixture, except decanoic acid. In the extraction of beverages such as red wine, the extraction element showed stronger adsorption characteristics for polar compounds such as alcohols and acids than a non-polar polydimethylsiloxane-based element. This feature is derived from the main polymer structure along with hydroxyl and amino groups present in the epoxy-based monolith polymer matrix. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The radiation chemistry of the purine bases within DNA and related model compounds

International Nuclear Information System (INIS)

Cadet, J.; Berger, M.; Shaw, A.

1986-01-01

Both the direct and indirect effects of ionizing radiations are believed to contribute to the chemical changes induced in cellular DNA. Relevant information on the possible degradation pathways has been provided by studies using DNA model compounds, the major proportion of which have focused on pyrimidine components and sugar derivatives. With the development of powerful analytical tools such as high performance liquid chromatography and soft ionization mass spectrometry techniques, progress has recently been made in the elucidation of the nature of the radiation-induced chemical modifications of purine bases in DNA and related nucleosides and nucleotides. This short review details recent aspects of the radiation-induced degradation of adenine and guanine bases in DNA and its model compounds as the result of both direct and indirect effects. 11 refs., 2 figs., 1 tab

Response of maize to reduced urea application combined with compound nitrogen fertilizer synergists

International Nuclear Information System (INIS)

Tian Xiuying; WANG Zhengyin

2006-01-01

Pot and field experiments were conducted to study the response to application rate of urea labeled with 15 N combined with compound nitrogen fertilizer synergists in the growth, yield, uptake and utilization rate of urea of maize. In pot experiment, the standard urea application rate is 120 mg/perpot; in field experiment, the standard urea application rate is 157.5 kg/hm 2 . Maize with 15 N-urea. The results showed that the growth of maize seedling was obviously promoted with appropriate dosage of compound nitrogen fertilizer synergists (20%-60% of N). The treatments of urea application rate reduced by 5%-15% and added compound nitrogen fertilizer synergists, the growth and nitrogen content of maize were not significant changed, and the total 15 N uptake and nitrogen uptake by maize were the same as CK 2 or increased a little. Nitrogen use efficiency of other treatments increased by 5.6%-7.3% comparing with CK, except the treatment of urea application rate reduced by 30%. The apparent utilization rate of nitrogen was enhanced by 7.7%-17.0%. Under the field condition, maize yield, total uptake, net uptake, physiological rate and agronomic use efficiency of nitrogen were the same as CK or increased. The apparent utilization rate of nitrogen was enhanced by 14.8%-15.2% treated with urea reduced by 5%-15% (7.8-23.7 kg/hm 2 ) and added with compound nitrogen fertilizer synergists. It was not helpful for the growth and nitrogen utilization rate of maize when urea reduced by 30% and combined with compound nitrogen fertilizer synergists. As a result, treated with urea decreased by 15% and combined with appropriate dosage of compound nitrogen fertilizer synergists (20% of urea), the growth and yield of maize had litter effect and higher the uptake and utilization of nitrogen. (authors)

Diverse Cd(II) compounds based on N-benzoyl-L-glutamic acid and N-donor ligands: Structures and photoluminescent properties

Science.gov (United States)

Ma, Ning; Guo, Wei-Ying; Song, Hui-Hua; Yu, Hai-Tao

2016-01-01

Five new Cd(II) coordination polymers with N-benzoyl-L-glutamic acid (H2bzgluO) and different N-donor ligands, [Cd(bzgluO)(2,2‧-bipy)(H2O)]n (1), [Cd(bzgluO)(2,4‧-bipy)2(H2O)·3H2O]n (2), [Cd(bzgluO)(phen)·H2O]n (3), [Cd(bzgluO)(4,4‧-bipy)(H2O)]n (4), [Cd(bzgluO)(bpp)(H2O)·2H2O]n (5) were synthesized (2,2‧-bipy=2,2‧-bipyridine, 2,4‧-bipy=2,4‧-bipyridine, phen=1,10-phenanthroline, 4,4‧-bipy=4,4‧-bipyridine, bpp=1,3-di(4-pyridyl)propane). Compounds 1-2 exhibit a 1D single-chain structure. Compound 1 generates a 2D supramolecular structure via π-π stacking and hydrogen bonding, 3D architecture of compound 2 is formed by hydrogen bonding. Compound 3 features a 1D double-chain structure, which are linked by π-π interactions into a 2D supramolecular layer. Compounds 4-5 display a 2D network structure. Neighboring layers of 4 are extended into a 3D supramolecular architecture through hydrogen bonding. The structural diversity of these compounds is attributed to the effect of ancillary N-donor ligands and coordination modes of H2bzgluO. Luminescent properties of 1-5 were studied at room temperature. Circular dichroism of compounds 1, 2 and 5 were investigated.

Electrochemical Removal of NOx-Gasses by Use of LSM-Cathodes Impregnated with a NOx Storage Compound

DEFF Research Database (Denmark)

Traulsen, Marie Lund; Kammer Hansen, Kent

2010-01-01

Electrochemical decomposition of NO on La0.85Sr0.15MnO3-- Ce0.90Gd0.10O1.95electrodes with and without KNO3 impregnation is investigated. The KNO3 is added as this compound is expected to work as a NOx-storage compound. Measurements are made in the temperature range 300-400 degree C and in three...... in the NO-conversion, when KNO3 is added to the La0.85Sr0.15MnO3-- Ce0.90Gd0.10O1.95electrodes. ©2010 COPYRIGHT ECS - The Electrochemical Society...

Organically functionalized mesoporous SBA-15 as sorbents for removal of selected pharmaceuticals from water

Energy Technology Data Exchange (ETDEWEB)

Bui, Tung Xuan [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712 (Korea, Republic of); Kang, Seo-Young [International Environmental Research Center (IERC), Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712 (Korea, Republic of); Lee, Sang-Hyup [Water Environment Center, Korea Institute of Science and Technology, Cheongryang, Seoul 130-650 (Korea, Republic of); Choi, Heechul, E-mail: hcchoi@gist.ac.kr [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712 (Korea, Republic of)

2011-10-15

Highlights: {yields} SBA-15 grafted with aminopropyl, hydroxymethyl, and trimethylsilyl groups as sorbents. {yields} Sorbents for removal of a mixture of 12 pharmaceuticals from water. {yields} Hydroxymethyl-SBA-15 shows similar adsorption efficiency like SBA-15. {yields} Aminopropyl-SBA-15 makes increase for clofibric acid, diclofenac, decrease for atenolol, estrone, trimethoprim. {yields} Trimethylsilyl-SBA-15 makes increase for 9 compounds; 7 compounds from 70.6% to 98.9%. - Abstract: Mesoporous silica SBA-15 and its postfunctionalized counterparts with hydroxymethyl (HM-SBA-15), aminopropyl (AP-SBA-15), and trimethylsilyl (TMS-SBA-15) were prepared and characterized by powder X-ray diffraction, N{sub 2} adsorption-desorption measurement, Fourier-transform infrared spectroscopy, and elemental analysis. The removal of a mixture of 12 selected pharmaceuticals was investigated by batch adsorption experiments onto SBA-15 and the grafted materials. SBA-15 showed to have moderate adsorption affinity with amino-containing (atenolol, trimethoprim) and hydrophobic pharmaceuticals, but it displayed minimal adsorption affinity toward hydrophilic compounds. HM-SBA-15 was analogous with SBA-15 in terms of the adsorption efficiency toward all pharmaceuticals. AP-SBA-15 exhibited an increase in the adsorption of two acidic compounds (clofibric acid, diclofenac) but a decrease in the adsorption of estrone and the two amino-containing compounds. Among the grafted materials, TMS-SBA-15 had the highest adsorption affinity toward most pharmaceuticals. Moreover, the adsorption of nine pharmaceuticals to TMS-SBA-15 was significantly higher than that to SBA-15; seven of which showed the removal percentages from 70.6% to 98.9% onto TMS-SBA-15. The number of pharmaceuticals showing high adsorption efficiency onto TMS-SBA-15 did not alter significantly as the pH changed in the range of 5.5-7.6. The results suggest that TMS-SBA-15 is a promising material for the removal of pharmaceuticals

Organically functionalized mesoporous SBA-15 as sorbents for removal of selected pharmaceuticals from water

International Nuclear Information System (INIS)

Bui, Tung Xuan; Kang, Seo-Young; Lee, Sang-Hyup; Choi, Heechul

2011-01-01

Highlights: → SBA-15 grafted with aminopropyl, hydroxymethyl, and trimethylsilyl groups as sorbents. → Sorbents for removal of a mixture of 12 pharmaceuticals from water. → Hydroxymethyl-SBA-15 shows similar adsorption efficiency like SBA-15. → Aminopropyl-SBA-15 makes increase for clofibric acid, diclofenac, decrease for atenolol, estrone, trimethoprim. → Trimethylsilyl-SBA-15 makes increase for 9 compounds; 7 compounds from 70.6% to 98.9%. - Abstract: Mesoporous silica SBA-15 and its postfunctionalized counterparts with hydroxymethyl (HM-SBA-15), aminopropyl (AP-SBA-15), and trimethylsilyl (TMS-SBA-15) were prepared and characterized by powder X-ray diffraction, N 2 adsorption-desorption measurement, Fourier-transform infrared spectroscopy, and elemental analysis. The removal of a mixture of 12 selected pharmaceuticals was investigated by batch adsorption experiments onto SBA-15 and the grafted materials. SBA-15 showed to have moderate adsorption affinity with amino-containing (atenolol, trimethoprim) and hydrophobic pharmaceuticals, but it displayed minimal adsorption affinity toward hydrophilic compounds. HM-SBA-15 was analogous with SBA-15 in terms of the adsorption efficiency toward all pharmaceuticals. AP-SBA-15 exhibited an increase in the adsorption of two acidic compounds (clofibric acid, diclofenac) but a decrease in the adsorption of estrone and the two amino-containing compounds. Among the grafted materials, TMS-SBA-15 had the highest adsorption affinity toward most pharmaceuticals. Moreover, the adsorption of nine pharmaceuticals to TMS-SBA-15 was significantly higher than that to SBA-15; seven of which showed the removal percentages from 70.6% to 98.9% onto TMS-SBA-15. The number of pharmaceuticals showing high adsorption efficiency onto TMS-SBA-15 did not alter significantly as the pH changed in the range of 5.5-7.6. The results suggest that TMS-SBA-15 is a promising material for the removal of pharmaceuticals from aqueous phase

Effects of Copper-based Compounds, Antibiotics and a Plant Activator on Population Sizes and Spread of Clavibacter michiganensis subsp. michiganensis in Greenhouse Tomato Seedlings

Directory of Open Access Journals (Sweden)

Svetlana Milijašević

2009-01-01

Full Text Available Three copper-based compounds (copper hydroxide, copper oxychloride, copper sulphate, two antibiotics (streptomycin and kasugamycin and a plant activator (ASM significantly reduced population sizes and spread of C. michiganensis subsp. michiganensis among tomatoseedlings in the greenhouse. Streptomycin had the best effect in reducing pathogen population size in all sampling regions. Moreover, this antibiotic completely stopped the spread of C. michiganensis subsp. michiganensis in the region most distant from the inoculumfocus. Copper hydroxide mixed with streptomycin significantly limited the pathogen population, compared with copper hydroxide alone, the other copper-based compounds, ASM and kasugamycin. However, combining streptomycin with copper hydroxide did notcontribute to its greater efficacy against the pathogen population. Copper-based compounds, in general, were less effective in limiting pathogen population sizes than the other treatments in all three sampling regions, primarily copper oxychloride and the combinationof copper hydroxide and mancozeb. Among copper compounds, copper hydroxide was the most prominent in reducing the bacterial population, especially in the region closest to the inoculum focus, while its combination with mancozeb did not improve the effects. Kasugamycin significantly limited pathogen population size, compared to copper bactericides, but it was less effective than the other antibiotic compound, i.e. streptomycin. The plant activator ASM significantly reduced population density, and it was more effectivewhen used three days prior to inoculation than six days before inoculation.

Toxic effects of copper-based nanoparticles or compounds to lettuce (Lactuca sativa) and alfalfa (Medicago sativa).

Science.gov (United States)

Hong, Jie; Rico, Cyren M; Zhao, Lijuan; Adeleye, Adeyemi S; Keller, Arturo A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

2015-01-01

The increased production and use of nanoparticles (NPs) has generated concerns about their impact on living organisms. In this study, nCu, bulk Cu, nCuO, bulk CuO, Cu(OH)2 (CuPRO 2005, Kocide 3000), and CuCl2 were exposed for 15 days to 10 days-old hydroponically grown lettuce (Lactuca sativa) and alfalfa (Medicago sativa). Each compound was applied at 0, 5, 10, and 20 mg L(-1). At harvest, we measured the size of the plants and determined the concentration of Cu, macro and microelements by using ICP-OES. Catalase and ascorbate peroxidase activity was also determined. Results showed that all Cu NPs/compounds reduced the root length by 49% in both plant species. All Cu NPs/compounds increased Cu, P, and S (>100%, >50%, and >20%, respectively) in alfalfa shoots and decreased P and Fe in lettuce shoot (>50% and >50%, respectively, excluding Fe in CuCl2 treatment). Biochemical assays showed reduced catalase activity in alfalfa (root and shoot) and increased ascorbate peroxidase activity in roots of both plant species. Results suggest that Cu NPs/compounds not only reduced the size of the plants but altered nutrient content and enzyme activity in both plant species.

Development and implementation of a compound converter in solar energy systems

Directory of Open Access Journals (Sweden)

S. J. B. Hartman

1992-07-01

Full Text Available The converter proposed here is a compound photovoltaic converter system that has been implemented with a power rating of 1,5 kVA at an array voltage of 96 V, using a 24 V battery bank. The converter system combines the functions of inversion, battery regulation and maximum power point tracking of the solar array into a single cost-effective converter. Maximum power point tracking is performed by controlling the voltage and frequency of the AC output. A description of this converter, and an explanation of the control strategy employed, are provided together with practical results measured on the prototype converter. This compound topology has a high conversion efficiency from solar array to load.

Isolation and identification of antibacterial compounds from Thymus kotschyanus aerial parts and Dianthus caryophyllus flower buds.

Science.gov (United States)

Mohammed, Muthanna J; Al-Bayati, Firas A

2009-06-01

The aerial parts of Thymus kotschyanus Boiss. and Hohen. (Lamiaceae) and flower buds of Dianthus caryophyllus L. (Caryophyllaceae) have been traditionally implemented in the treatment of wounds, throat and gum infections and gastro-intestinal disorder by the indigenous people of northern Iraq, although the compounds responsible for the medicinal properties have not been identified. In this study, antibacterial compounds from both plants were isolated and characterized, and the biological activity of each compound was assessed individually and combined. Compounds were isolated and characterized from the extracted essential oils of both plants using different spectral techniques: TLC, FTIR spectra and HPLC. The minimum inhibitory concentrations MIC values for the compounds were assessed individually and combined based on a microdilution and the checkerboard method in 96 multi-well microtiter plates. Two known compounds were isolated from the essential oils of both plants and were identified as thymol and eugenol. The isolated compounds were investigated for their single and combined antibacterial activities against seven selected pathogenic bacteria; Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Proteus mirabilis, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. Thymol MIC values ranged from 15.6 to 250.0 microg/ml and B. cereus was found to be the most sensitive pathogen with a MIC value of 15.6 microg/ml. Eugenol achieved stronger MIC values against most tested pathogens and the best MIC value (15.6 microg/ml) was observed against B. cereus, L. monocytogenes and K. pneumoniae whereas, S. aureus, P. mirabilis and E. coli were inhibited with a MIC value of 31.2 microg/ml. Combination results had antibacterial enhancement against most pathogens and the best synergistic result was seen against P. mirabilis and E. coli. The isolation of two antibacterial compounds from Thymus kotschyanus aerial parts and Dianthus caryophyllus flower

Template-based combinatorial enumeration of virtual compound libraries for lipids.

Science.gov (United States)

Sud, Manish; Fahy, Eoin; Subramaniam, Shankar

2012-09-25

A variety of software packages are available for the combinatorial enumeration of virtual libraries for small molecules, starting from specifications of core scaffolds with attachments points and lists of R-groups as SMILES or SD files. Although SD files include atomic coordinates for core scaffolds and R-groups, it is not possible to control 2-dimensional (2D) layout of the enumerated structures generated for virtual compound libraries because different packages generate different 2D representations for the same structure. We have developed a software package called LipidMapsTools for the template-based combinatorial enumeration of virtual compound libraries for lipids. Virtual libraries are enumerated for the specified lipid abbreviations using matching lists of pre-defined templates and chain abbreviations, instead of core scaffolds and lists of R-groups provided by the user. 2D structures of the enumerated lipids are drawn in a specific and consistent fashion adhering to the framework for representing lipid structures proposed by the LIPID MAPS consortium. LipidMapsTools is lightweight, relatively fast and contains no external dependencies. It is an open source package and freely available under the terms of the modified BSD license.

Internal friction due to domain-wall motion in martensitically transformed A15 compounds

International Nuclear Information System (INIS)

Snead, C.L. Jr.; Welch, D.O.

1985-01-01

A lattice instability in A15 materials in some cases leads to a cubic-to-tetragonal martensitic transformation at low temperatures. The transformed material orients in lamellae with c axes alternately aligned along the directions producing domain walls between the lamellae. An internal-friction (delta) feature below T/sub m/ is attributed to stress-induced domain-wall motion. The magnitude of the friction increases as temperature is lowered below T/sub m/ as (1-c/a) increases, and behaves as (1-c/a) 2 from T/sub m/ down to the superconducting critical temperature where the increasing tetragonality is inhibited. The effect of strain in the lattice is to decrease the domain-wall internal friction, but not affect T/sub m/. Neutron-induced disorder and the addition of some third-elements in alloying decrease both delta and T/sub m/, with some elements reducing only the former. Less than 1 at. % H is seen to completely suppress both delta and T/sub m. Martensitically transformed V 2 Zr demonstrates low-temperature internal-friction and modulus behavior consists with easy β/m wall motion relative to the easy m/m motion of the A15's. For the V 2 Zr, a peak in delta is observed, qualitatively in agreement with expected β/m wall motion

Matrix- and tensor-based recommender systems for the discovery of currently unknown inorganic compounds

Science.gov (United States)

Seko, Atsuto; Hayashi, Hiroyuki; Kashima, Hisashi; Tanaka, Isao

2018-01-01

Chemically relevant compositions (CRCs) and atomic arrangements of inorganic compounds have been collected as inorganic crystal structure databases. Machine learning is a unique approach to search for currently unknown CRCs from vast candidates. Herein we propose matrix- and tensor-based recommender system approaches to predict currently unknown CRCs from database entries of CRCs. Firstly, the performance of the recommender system approaches to discover currently unknown CRCs is examined. A Tucker decomposition recommender system shows the best discovery rate of CRCs as the majority of the top 100 recommended ternary and quaternary compositions correspond to CRCs. Secondly, systematic density functional theory (DFT) calculations are performed to investigate the phase stability of the recommended compositions. The phase stability of the 27 compositions reveals that 23 currently unknown compounds are newly found to be stable. These results indicate that the recommender system has great potential to accelerate the discovery of new compounds.

Synthesis and Application of Polymeric Fluorescent Compounds Based on Coumarin

Directory of Open Access Journals (Sweden)

Guojun Liu

2015-06-01

Full Text Available In this work, a multifunctional yellowing inhibitor was synthesized by the Pechmann method. In order to obtain the target compound, 7-hydroxy-4-methyl coumarin was prepared by using the raw materials of resorcinol and ethyl acetoacetate, with toluene-p-sulfonic acid as the catalyst. New polymeric fluorescent compounds were synthesized by connecting the 7-hydroxy-4-methyl coumarin, the hindered amine light stabilizer 4-amion-2,2,6,6-tetramentylniperidine, and a series of polyethylene glycol segments into the same molecule with cyanuric chloride as a bridge. The structures of the synthesized molecules were confirmed by FT-IR, 1H NMR, and elemental analysis. The luminescent properties of the fluorescent compounds were studied by UV-vis spectroscopy and fluorescence spectroscopy. The integration effect between the fluorescent compounds and paper was tested by a scanning electron microscope. The light stability effect on the paper sheet was tested using an ultraviolet aging apparatus. The results indicate that the polymeric fluorescent compounds had a positive effect on the light stability of the high-yield pulp.

Experimental investigation of densification of powdered A15 phase in the system Nb--Al--Ge

International Nuclear Information System (INIS)

Modi, D.P.

1976-02-01

An investigation of the densification of precompounded powder of the A15 phase Nb 3 (Al,Ge) was made. The influence of various parameters such as additives, temperature, pressure and time in sintering of this material was studied. Since cold pressing followed by sintering did not produce sufficient density, the hot pressing technique was used. By hot pressing at 1450 0 C for 1 / 2 hour under 6 ksi pressure, about 95 percent densification was achieved. Results provide information that could lead to the development of a viable process for producing superconductors based on this compound. 14 figures, 17 references

Three coordination compounds based on benzene tetracarboxylate ...

Indian Academy of Sciences (India)

YUNLONG WU

nescence, considerable attention has been focused on the construction of coordination .... measurements were performed on ground powder samples at .... Figure 2. (a) Coordination environment of Co1 ion in compound 2. (b) Coordination.

Development and Sequential Analysis of a New Multi-Agent, Anti-Acne Formulation Based on Plant-Derived Antimicrobial and Anti-Inflammatory Compounds

Directory of Open Access Journals (Sweden)

Crina Saviuc

2017-01-01

Full Text Available The antibacterial and anti-inflammatory potential of natural, plant-derived compounds has been reported in many studies. Emerging evidence indicates that plant-derived essential oils and/or their major compounds may represent a plausible alternative treatment for acne, a prevalent skin disorder in both adolescent and adult populations. Therefore, the purpose of this study was to develop and subsequently analyze the antimicrobial activity of a new multi-agent, synergic formulation based on plant-derived antimicrobial compounds (i.e., eugenol, β-pinene, eucalyptol, and limonene and anti-inflammatory agents for potential use in the topical treatment of acne and other skin infections. The optimal antimicrobial combinations selected in this study were eugenol/β-pinene/salicylic acid and eugenol/β-pinene/2-phenoxyethanol/potassium sorbate. The possible mechanisms of action revealed by flow cytometry were cellular permeabilization and inhibition of efflux pumps activity induced by concentrations corresponding to sub-minimal inhibitory (sub-MIC values. The most active antimicrobial combination represented by salycilic acid/eugenol/β-pinene/2-phenoxyethanol/potassium sorbate was included in a cream base, which demonstrated thermodynamic stability and optimum microbiological characteristics.

Chemomics-based marker compounds mining and mimetic processing for exploring chemical mechanisms in traditional processing of herbal medicines, a continuous study on Rehmanniae Radix.

Science.gov (United States)

Zhou, Li; Xu, Jin-Di; Zhou, Shan-Shan; Shen, Hong; Mao, Qian; Kong, Ming; Zou, Ye-Ting; Xu, Ya-Yun; Xu, Jun; Li, Song-Lin

2017-12-29

Exploring processing chemistry, in particular the chemical transformation mechanisms involved, is a key step to elucidate the scientific basis in traditional processing of herbal medicines. Previously, taking Rehmanniae Radix (RR) as a case study, the holistic chemome (secondary metabolome and glycome) difference between raw and processed RR was revealed by integrating hyphenated chromatographic techniques-based targeted glycomics and untargeted metabolomics. Nevertheless, the complex chemical transformation mechanisms underpinning the holistic chemome variation in RR processing remain to be extensively clarified. As a continuous study, here a novel strategy by combining chemomics-based marker compounds mining and mimetic processing is proposed for further exploring the chemical mechanisms involved in herbal processing. First, the differential marker compounds between raw and processed herbs were rapidly discovered by untargeted chemomics-based mining approach through multivariate statistical analysis of the chemome data obtained by integrated metabolomics and glycomics analysis. Second, the marker compounds were mimetically processed under the simulated physicochemical conditions as in the herb processing, and the final reaction products were chemically characterized by targeted chemomics-based mining approach. Third, the main chemical transformation mechanisms involved were clarified by linking up the original marker compounds and their mimetic processing products. Using this strategy, a set of differential marker compounds including saccharides, glycosides and furfurals in raw and processed RR was rapidly found, and the major chemical mechanisms involved in RR processing were elucidated as stepwise transformations of saccharides (polysaccharides, oligosaccharides and monosaccharides) and glycosides (iridoid glycosides and phenethylalcohol glycosides) into furfurals (glycosylated/non-glycosylated hydroxymethylfurfurals) by deglycosylation and/or dehydration. The

Leaching characteristics of calcium-based compounds in MSWI Residues: From the viewpoint of clogging risk

International Nuclear Information System (INIS)

Xia, Yi; Zhang, Hua; Phoungthong, Khamphe; Shi, Dong-Xiao; Shen, Wen-Hui; Shao, Li-Ming; He, Pin-Jing

2015-01-01

Highlights: • The leaching behavior of Ca-based compounds commonly in MSWI residues was studied. • pH is the crucial factor for calcium leaching process. • CaCO 3 was the most sensitive to leaching temperature and Ca 3 (PO 4 ) 2 was the least. • Ca leaching of MSWIBA and SAPCR attributed to CaCO 3 and Ca 3 (PO 4 ) 2 respectively. • Potential clogging ability of MSWI residues leachate in open air was calculated. - Abstract: Leachate collection system (LCS) clogging caused by calcium precipitation would be disadvantageous to landfill stability and operation. Meanwhile, calcium-based compounds are the main constituents in both municipal solid waste incineration bottom ash (MSWIBA) and stabilized air pollution control residues (SAPCR), which would increase the risk of LCS clogging once these calcium-rich residues were disposed in landfills. The leaching behaviors of calcium from the four compounds and municipal solid waste incineration (MSWI) residues were studied, and the influencing factors on leaching were discussed. The results showed that pH was the crucial factor in the calcium leaching process. CaCO 3 and CaSiO 3 began leaching when the leachate pH decreased to less than 7 and 10, respectively, while Ca 3 (PO 4 ) 2 leached at pH < 12. CaSO 4 could hardly dissolve in the experimental conditions. Moreover, the sequence of the leaching rate for the different calcium-based compounds is as follows: CaSiO 3 > Ca 3 (PO 4 ) 2 > CaCO 3 . The calcium leaching from the MSWIBA and SAPCR separately started from pH < 7 and pH < 12, resulting from CaCO 3 and Ca 3 (PO 4 ) 2 leaching respectively, which was proven by the X-ray diffraction results. Based on the leaching characteristics of the different calcium compounds and the mineral phase of calcium in the incineration residues, simulated computation of their clogging potential was conducted, providing the theoretical basis for the risk assessment pertaining to LCS clogging in landfills

Natural Bioactive Compounds from Winery By-Products as Health Promoters: A Review

Directory of Open Access Journals (Sweden)

Ana Teixeira

2014-09-01

Full Text Available The relevance of food composition for human health has increased consumers’ interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L. are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used. Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health.

Natural bioactive compounds from winery by-products as health promoters: a review.

Science.gov (United States)

Teixeira, Ana; Baenas, Nieves; Dominguez-Perles, Raul; Barros, Ana; Rosa, Eduardo; Moreno, Diego A; Garcia-Viguera, Cristina

2014-09-04

The relevance of food composition for human health has increased consumers' interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L.) are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used). Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health.

Gas chromatography and isotope ratio mass spectrometry of Pinot Noir wine volatile compounds (δ13C) and solid residues (δ13C, δ15N) for the reassessment of vineyard water-status.

Science.gov (United States)

Spangenberg, Jorge E; Vogiatzaki, Maria; Zufferey, Vivian

2017-09-29

This paper describes a novel approach to reassess the water status in vineyards based on compound-specific isotope analysis (CSIA) of wine volatile organic compounds (δ 13 C VOC/VPDB ) and bulk carbon and nitrogen isotopes, and the C/N molar ratios of the wine solid residues (δ 13 C SR/VPDB , δ 15 N SR/Air-N2 ). These analyses link gas chromatography/combustion and elemental analysis to isotope ratio mass spectrometry (GC/C/IRMS, EA/IRMS). Field-grown cultivars of Pinot Noir grapevines were exposed during six growing seasons (2009-2014) to controlled soil water availability, while maintaining identical the other environmental variables and agricultural techniques. Wines were produced from the grapes by the same oenological protocol. This permitted for the assessment of the effects in the biochemistry of wines solely induced by the changes in the plant-soil water status. This mimicked the more recurrent and prolonged periods of soil water deficiency due to climate changes. Water stress in grapevine was assessed by the measurement of the predawn leaf water potential (Ψ pd ) and the stable carbon isotope composition of the berry sugars during harvest (must sugars). For quantitation purposes and the normalization of the measured stable carbon isotope ratios of the VOCs, the wine samples were spiked with three standard compounds with known concentration and δ 13 C VPDB values. VOCs were extracted by liquid-liquid extraction and analyzed by gas chromatography/flame ionization detection (GC/FID), gas chromatography/mass spectrometry (GC/MS), and GC/C/IRMS. δ 13 C values were obtained for eighteen VOCs. The solid residues were obtained by freeze-drying wine aliquots and were analyzed for their C and N content and isotope composition by EA/IRMS. All the isotopic ratios (δ 13 C SR , δ 15 N SR , δ 13 C VOC ) are highly correlated with the Ψ pd values, indicating that the proposed gas chromatography and isotope ratio mass spectrometry approach is a useful tool to

Stability, Reactivity, and Constituent Interaction in TiSe2-Based Metastable Misfit Layer Compounds Synthesized from Designed Amorphous Precursors

Science.gov (United States)

Merrill, Devin R.

A series of intergrowth compounds with the basic formula [(MSe) 1+delta]m(TiSe2)n are reported. The compounds are prepared from modulated elemental reactants and display interesting structural and electronic behavior. Section 1 of this dissertation outlines initial attempts to characterize constituent interaction. The first member of the SnSe based subclass is reported and displays the highest Seebeck coefficient of any m = n = 1 compound reported to date, and a surprising amount of order is observed, compared to previously reported compounds. With properly established deposition parameters, the synthesis was extended to included the m = 2-4 compounds. These compounds display interesting electronic behavior that suggests the band structure shifts considerably as the SnSe block is expanded, affecting the interaction between the constituent layers. The first compound based on BiSe is then reported, suggesting that the Bi structure donates more conduction electrons to the band structure. Targeted substitution through kinetic control is the focus of Section 2, and a family of (PbxSn1-xSe)1+deltaTiSe 2 is reported over the entire range of x, even though a miscibility gap exists in the bulk PbxSn1-xSe system. The resulting alloyed intergrowth compounds also display equal or higher mobility than the end members, suggesting modulation doping could be used to affect transport properties. As a proof of principle, the analogous system based on a Bi xSn1-xSe constituent was prepared to attempt to systematically affect carrier concentration. It was found that while carrier concentration can be controlled, the evolving structure affects the doping efficiency of the Bi atoms and mobility in the structure. Section 3 outlines attempts to form higher order TiSe2-based heterostructures and the important chemical considerations observed during the preparation of these materials. The 3 component systems in the Pb-Sn-Ti-Se system can be formed at low temperature, with SnSe2 rather than

Development and optimization of a cell-based assay for the selection of synthetic compounds that potentiate bone morphogenetic protein-2 activity.

Science.gov (United States)

Okada, Motohiro; Sangadala, Sreedhara; Liu, Yunshan; Yoshida, Munehito; Reddy, Boojala Vijay B; Titus, Louisa; Boden, Scott D

2009-12-01

reliability of our cell-based assay. Direct delivery of synthesized protein can be limited by high cost, instability or inadequate post-translational modifications. Thus, there would be a clear benefit for a low cost, cell penetrable chemical compound. We successfully used our gene expression-based assay to choose an active compound from a select group of compounds that were identified by computational screenings as the most likely candidates for mimicking the function of LMP-1. Among them, we selected SVAK-3, a compound that showed a dose-dependent potentiation of BMP-2 activity in inducing osteoblastic differentiation of C2C12 cells. We show that either the full length LMP-1 protein or its potential mimetic compound consistently exhibit similar potentiation of BMP-2 activity even when multiple markers of the osteoblastic phenotype were parallely monitored.

Synthesis and Antimicrobial Activity of New Schiff Base Compounds Containing 2-Hydroxy-4-pentadecylbenzaldehyde Moiety

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Gadada Naganagowda

2014-01-01

Full Text Available Various novel Schiff base compounds have been synthesized by reaction of 2-hydroxy-4-pentadecylbenzaldehyde with substituted benzothiophene-2-carboxylic acid hydrazide and different substituted aromatic or heterocyclic amines in the presence of acetic acid in ethanol. The structures of all these compounds were confirmed by elemental analysis, IR, 1H-NMR, 13C-NMR, and mass spectral data and have been screened for antibacterial and antifungal activity.

Cu{sub 1.5}Mn{sub 1.5}O{sub 4}-based ceramic spectrally selective coatings for efficient solar absorber applications

Energy Technology Data Exchange (ETDEWEB)

Ma, Pengjun [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing, 100049 (China); Geng, Qingfen; Gao, Xianghu [Research & Development Center for Eco-material and Eco-chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Yang, Shengrong [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Liu, Gang, E-mail: gangliu@licp.cas.cn [Research & Development Center for Eco-material and Eco-chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China)

2016-08-05

Cu{sub 1.5}Mn{sub 1.5}O{sub 4}-based ceramic spectrally selective (CSS) coating was deposited on aluminum substrate using a sol–gel dip-coating method. The citric acid introduced in the precursor system lowered the required calcining temperature of crystalline Cu{sub 1.5}Mn{sub 1.5}O{sub 4}. X-Ray diffraction (XRD) peaks of coatings annealed above 450 °C were found to coincide exactly with that of crystalline Cu{sub 1.5}Mn{sub 1.5}O{sub 4} in JCPDS database. By optimizing the withdrawal rate and calcining temperature, coating with spectral selectivity as good as α{sub s} = 0.876 and ε{sub 100} = 0.057 was achieved after only one dipping/annealing cycle. Subjected to an accelerated ageing test at 259 °C, the obtained CSS coating showed an excellent thermally durability with the performance criterion (PC) values below 0.05. - Highlights: • Cu{sub 1.5}Mn{sub 1.5}O{sub 4}-based CSS coating is achieved after only one dipping/annealing cycle. • Cu{sub 1.5}Mn{sub 1.5}O{sub 4} coating is obtained as the annealing temperature reaches to 450 °C. • Cu{sub 1.5}Mn{sub 1.5}O{sub 4} coating exhibits optical parameter: α{sub s} = 0.876 and ε{sub 100} = 0.057. • Cu{sub 1.5}Mn{sub 1.5}O{sub 4} coating shows the excellent stability in low to mid temperature region.

An approach to accidents modeling based on compounds road environments.

Science.gov (United States)

Fernandes, Ana; Neves, Jose

2013-04-01

The most common approach to study the influence of certain road features on accidents has been the consideration of uniform road segments characterized by a unique feature. However, when an accident is related to the road infrastructure, its cause is usually not a single characteristic but rather a complex combination of several characteristics. The main objective of this paper is to describe a methodology developed in order to consider the road as a complete environment by using compound road environments, overcoming the limitations inherented in considering only uniform road segments. The methodology consists of: dividing a sample of roads into segments; grouping them into quite homogeneous road environments using cluster analysis; and identifying the influence of skid resistance and texture depth on road accidents in each environment by using generalized linear models. The application of this methodology is demonstrated for eight roads. Based on real data from accidents and road characteristics, three compound road environments were established where the pavement surface properties significantly influence the occurrence of accidents. Results have showed clearly that road environments where braking maneuvers are more common or those with small radii of curvature and high speeds require higher skid resistance and texture depth as an important contribution to the accident prevention. Copyright © 2013 Elsevier Ltd. All rights reserved.

New cytotoxic and anti-inflammatory compounds isolated from Morus alba L.

Science.gov (United States)

Qin, Jing; Fan, Min; He, Juan; Wu, Xing-De; Peng, Li-Yan; Su, Jia; Cheng, Xiao; Li, Yan; Kong, Ling-Mei; Li, Rong-Tao; Zhao, Qin-Shi

2015-01-01

Six Diels-Alder adducts (1-6) and nine prenylated flavanones (7-15) were isolated from the root bark of Morus alba L. Among them, soroceal B (1) and sanggenol Q (7) were new compounds. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR techniques. Compounds 1-3, 9, 10, 12, 13 and 15 exhibited cytotoxic activity against five human tumour lines and compound 2 inhibited significantly selective cytotoxic activities towards HL-60 and AGS cells with IC50 of 3.4 and 3.6 μM. Compounds 3, 5, 9 and 12 exhibited moderate inhibitory activity against nitric oxide production in LPS-activated RAW264.7.

Two 8-Hydroxyquinolinate Based Supramolecular Coordination Compounds: Synthesis, Structures and Spectral Properties

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Chengfeng Zhu

2017-03-01

Full Text Available Two new Cr(III complexes based on 2-substituted 8-hydroxyquinoline ligands, namely [Cr(L13] (1, (HL1=(E-2-[2-(4-nitro-phenyl-vinyl]-8-hydroxy-quinoline and [Cr(L23] (2, (HL2=(E-2-[2-(4-chloro-phenylvinyl]-8-hydroxy-quinoline, were prepared by a facile hydrothermal method and characterized thoroughly by single crystal X-ray diffraction, powder X-ray diffraction, FTIR, TGA, ESI-MS, UV-Visible absorption spectra and fluorescence emission spectra. Single crystal X-ray diffraction analyses showed that the two compounds featured 3D supramolecular architectures constructed from noncovalent interactions, such as π···π stacking, C-H···π, C-H···O, C-Cl···π, C-H···Cl interactions. The thermogravimetric analysis and ESI-MS study of compounds 1 and 2 suggested that the Cr(III complexes possessed good stability both in solid and solution. In addition, the ultraviolet and fluorescence response of the HL1 and HL2 shown marked changes upon their complexation with Cr(III ion, which indicated that the two 8-hydroxyquinolinate based ligand are promising heavy metal chelating agent for Cr3+.

1,5-Bis (2-Hydroxyphenyl)Pent-1,4-Diene-3-One: A Lead ...

African Journals Online (AJOL)

NJD

occurring chalcone nucleus to design effective antibacterial agents. The present investigation established 1,5-bis(2-hydroxyphenyl)pent-1,4-diene-3-one (1c) as a lead compound with potential against a panel of pathogenic bacterial strains, ...

Synthesis, biological evaluation and structure-activity correlation study of a series of imidazol-based compounds as Candida albicans inhibitors.

Science.gov (United States)

Moraca, Francesca; De Vita, Daniela; Pandolfi, Fabiana; Di Santo, Roberto; Costi, Roberta; Cirilli, Roberto; D'Auria, Felicia Diodata; Panella, Simona; Palamara, Anna Teresa; Simonetti, Giovanna; Botta, Maurizio; Scipione, Luigi

2014-08-18

A new series of 2-(1H-imidazol-1-yl)-1-phenylethanol derivatives was synthesized. The antifungal activity was evaluated in vitro against different fungal species. The biological results show that the most active compounds possess an antifungal activity comparable or higher than Fluconazole against Candida albicans, non-albicans Candida species, Cryptococcus neoformans and dermathophytes. Because of their racemic nature, the most active compounds 5f and 6c were tested as pure enantiomers. For 6c the (R)-enantiomer resulted more active than the (S)-one, otherwise for 5f the (S)-enantiomer resulted the most active. To rationalize the experimental data, a ligand-based computational study was carried out; the results of the modelling study show that (S)-5f and (R)-6c perfectly align to the ligand-based model, showing the same relative configuration. Preliminary studies on the human lung adenocarcinoma epithelial cells (A549) have shown that 6c, 5e and 5f possess a low cytotoxicity. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Compounding medications in a rural setting: an interprofessional perspective

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Taylor S

2018-04-01

Full Text Available Selina Taylor,1 Catherine Hays,1 Beverley Glass2 1Mount Isa Centre for Rural and Remote Health, James Cook University, Mount Isa, QLD, Australia; 2College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia Background: Interprofessional learning (IPL which focuses on the pharmacist’s role in specialty practices as part of a multidisciplinary health care team has not been explored. This study aimed to determine health care students’ understanding of the role of the pharmacist in compounding medications to optimize health outcomes for patients in rural and remote health care services.Methods: Four workshops followed by focus group interviews were conducted with undergraduate pharmacy, medical, nursing, physiotherapy, dentistry, Aboriginal public health, and speech pathology students (n=15. After an introductory lecture, students working in multidisciplinary teams undertook to compound three products. Focus groups were held at the end of the compounding workshops to explore students’ understanding and perceptions of these compounding activities. Thematic analysis was undertaken on the qualitative data obtained from the focus groups.Results: Student participants responded positively both to the opportunity to undertake a compounding exercise and being part of an interprofessional team, perceiving benefit for their future rural and remote health practice. Four major themes emerged from the qualitative analysis: improved knowledge and understanding; application to practice; interprofessional collaboration; and rural, remote, and Indigenous context. Students acknowledged that the workshops improved their understanding of the role of the pharmacist in compounding and how they, as part of a multidisciplinary team, could deliver better health outcomes for patients with special needs, especially in a rural and remote context.Conclusion: This study highlights that workshops of this nature have a role to play in developing

Use of tritium in the production of selfluminous compounds

International Nuclear Information System (INIS)

Jung, Heung Suk; Ahn, Doh Heui; Baek, Seung Woo; Koo, Je Hyoo; Kook, Il Hyun; Lee, Han Soo; Kim, Kwang Lak

1994-12-01

In a Pressurized Heavy Water Reactor, about one MCi of tritium is produced annually. Tritium is a very useful resource as an essential material for selfluminous compounds. In this report, in order to manufacture selfluminous compounds by using the tritium in Wolsung nuclear power plant, the pretreatment technology of materials and the coating technology of selfluminous compounds was investigated and its raw cost was estimated. It was confirmed that tritium can be used as a very useful industrial material. 5 figs., 15 tabs., 35 refs. (Author)

Discovery of 8-Amino-imidazo[1,5- a ]pyrazines as Reversible BTK Inhibitors for the Treatment of Rheumatoid Arthritis

Energy Technology Data Exchange (ETDEWEB)

Liu, Jian; Guiadeen, Deodial; Krikorian, Arto; Gao, Xiaolei; Wang, James; Boga, Sobhana Babu; Alhassan, Abdul-Basit; Yu, Younong; Vaccaro, Henry; Liu, Shilan; Yang, Chundao; Wu, Hao; Cooper, Alan; de Man, Jos; Kaptein, Allard; Maloney, Kevin; Hornak, Viktor; Gao, Ying-Duo; Fischmann, Thierry O.; Raaijmakers, Hans; Vu-Pham, Diep; Presland, Jeremy; Mansueto, My; Xu, Zangwei; Leccese, Erica; Zhang-Hoover, Jie; Knemeyer, Ian; Garlisi, Charles G.; Bays, Nathan; Stivers, Peter; Brandish, Philip E.; Hicks, Alexandra; Kim, Ronald; Kozlowski, Joseph A. (Merck); (WuXi App Tec)

2016-02-11

Bruton’s tyrosine kinase (BTK) is a Tec family kinase with a well-defined role in the B cell receptor (BCR) pathway. It has become an attractive kinase target for selective B cell inhibition and for the treatment of B cell related diseases. We report a series of compounds based on 8-amino-imidazo[1,5-a]pyrazine that are potent reversible BTK inhibitors with excellent kinase selectivity. Selectivity is achieved through specific interactions of the ligand with the kinase hinge and driven by aminopyridine hydrogen bondings with Ser538 and Asp539, and by hydrophobic interaction of trifluoropyridine in the back pocket. These interactions are evident in the X-ray crystal structure of the lead compounds 1 and 3 in the complex with the BTK enzyme. Our lead compounds show desirable PK profiles and efficacy in the preclinical rat collagen induced arthritis model.

A field-deployable compound-specific isotope analyzer based on quantum cascade laser and hollow waveguide

Science.gov (United States)

Wu, Sheng; Deev, Andrei

2013-01-01

A field deployable Compound Specific Isotope Analyzer (CSIA) coupled with capillary chromatogrpahy based on Quantum Cascade (QC) lasers and Hollow Waveguide (HWG) with precision and chemical resolution matching mature Mass Spectroscopy has been achieved in our laboratory. The system could realize 0.3 per mil accuracy for 12C/13C for a Gas Chromatography (GC) peak lasting as short as 5 seconds with carbon molar concentration in the GC peak less than 0.5%. Spectroscopic advantages of HWG when working with QC lasers, i.e. single mode transmission, noiseless measurement and small sample volume, are compared with traditional free space and multipass spectroscopy methods.

Distribution of volatile organic compounds over a semiconductor Industrial Park in Taiwan.

Science.gov (United States)

Chiu, Kong-Hwa; Wu, Ben-Zen; Chang, Chih-Chung; Sree, Usha; Lo, Jiunn-Guang

2005-02-15

This study examined volatile organic compounds (VOC) concentration in ambient air collected during the years 2000--2003 at several different locations of Hsinchu Science-based Industrial Park (HSIP) in Taiwan. A canister automated GC-MS system analyzed the volatile organics in ambient air grasp samples according to T0-15 method. Oxygenated volatiles were the most abundant VOC detected in HSIP followed by aromatics that are commonly used as solvents in the semiconductor industries. The major components measured in the ambient air are 2-propanol (29-135 ppbv), acetone (12-164 ppbv), benzene (0.7-1.7 ppbv), and toluene (13-20 ppbv). At some of the sampling locations, odorous compounds such as carbon disulfide and dimethyl sulfide levels exceed threshold values. The estimated toluene/benzene ratio is very high at most of the sites. However, the total amount of VOC is reduced over the years from 2000 to 2003 due to strict implementation on use and discharge of solvents in industries. There exists no definite seasonal pattern for sporadic occurrence of high levels of some of the volatile organics. Stagnant weather conditions with low wind speeds aid accumulation of toxic species at ground level. The results entail that hi-tech semiconductor industries are still a potential source for harmful organic substances to surrounding microenvironment.

An alkali ion source based on graphite intercalation compounds for ion mobility spectrometry

International Nuclear Information System (INIS)

Tabrizchi, Mahmoud; Hosseini, Zahra S

2008-01-01

A variety of alkali cation emitters were developed as the ion source for ion mobility spectrometry. The cation emitters were constructed based on alkali ion graphite intercalation compounds (GICs). The compounds were prepared by fusing alkali salts with ground graphite. In order to produce alkali ions, the compounds were loaded on a filament and heated to red. Reactant ions of the form alk + ions were observed for the alkali salts NaCl, KCl.LiCl, CsCl and SrCl. In addition to Na + ions, K + ions were observed at the beginning of thermionic emission from Na-GIC. This is due to the low ionization potential of potassium that exists in trace amounts in sodium salts. In addition to the potassium ion, Na + was observed in the case of LiCl salt. The Na + and K + peaks originating from impurities totally disappeared after about 40 min. However, the thermionic emission of the main ion of the corresponding salt lasted for several days. No negative ions were observed upon reversing the drift field. Selected organic compounds (methyl isobutyl ketone, dimethyl sulfoxide, acetone and tetrahydrofuran) were also ionized via alkali cation attachment reaction. Distinct ion mobility patterns were observed for different substances using one type of alkali reactant ion. However, the ion mobility pattern for a given substance changed when a different alkali reactant ion was used. Ammonia and amines were not ionized when this source was used

Sub-cellular localisation of a 15N-labelled peptide vector using NanoSIMS imaging

Science.gov (United States)

Römer, Winfried; Wu, Ting-Di; Duchambon, Patricia; Amessou, Mohamed; Carrez, Danièle; Johannes, Ludger; Guerquin-Kern, Jean-Luc

2006-07-01

Dynamic SIMS imaging is proposed to map sub-cellular distributions of isotopically labelled, exogenous compounds. NanoSIMS imaging allows the characterisation of the intracellular transport pathways of exogenous molecules, including peptide vectors employed in innovative therapies, using stable isotopes as molecular markers to detect the compound of interest. Shiga toxin B-subunit (STxB) was chosen as a representative peptide vector. The recombinant protein ( 15N-STxB) was synthesised in Escherichia coli using 15NH 4Cl as sole nitrogen source resulting in 15N enrichment in the molecule. Using the NanoSIMS 50 ion microprobe (Cameca), different ion species ( 12C 14N -, 12C 15N -, 31P -) originating from the same sputtered micro volume were simultaneously detected. High mass resolving power enabled the discrimination of 12C 15N - from its polyatomic isobars of mass 27. We imaged the membrane binding and internalisation of 15N-STxB in HeLa cells at spatial resolutions of less than 100 nm. Thus, the use of rare stable isotopes like 15N with dynamic SIMS imaging permits sub-cellular detection of isotopically labelled, exogenous molecules and imaging of their transport pathways at high mass and spatial resolution. Application of stable isotopes as markers can replace the large and chemically complex tags used for fluorescence microscopy, without altering the chemical and physical properties of the molecule.

Emissions of volatile organic compounds inferred from airborne flux measurements over a megacity

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T. Karl

2009-01-01

Full Text Available Toluene and benzene are used for assessing the ability to measure disjunct eddy covariance (DEC fluxes of Volatile Organic Compounds (VOC using Proton Transfer Reaction Mass Spectrometry (PTR-MS on aircraft. Statistically significant correlation between vertical wind speed and mixing ratios suggests that airborne VOC eddy covariance (EC flux measurements using PTR-MS are feasible. City-median midday toluene and benzene fluxes are calculated to be on the order of 14.1±4.0 mg/m²/h and 4.7±2.3 mg/m²/h, respectively. For comparison the adjusted CAM2004 emission inventory estimates toluene fluxes of 10 mg/m²/h along the footprint of the flight-track. Wavelet analysis of instantaneous toluene and benzene measurements during city overpasses is tested as a tool to assess surface emission heterogeneity. High toluene to benzene flux ratios above an industrial district (e.g. 10–15 g/g including the International airport (e.g. 3–5 g/g and a mean flux (concentration ratio of 3.2±0.5 g/g (3.9±0.3 g/g across Mexico City indicate that evaporative fuel and industrial emissions play an important role for the prevalence of aromatic compounds. Based on a tracer model, which was constrained by BTEX (BTEX– Benzene/Toluene/Ethylbenzene/m, p, o-Xylenes compound concentration ratios, the fuel marker methyl-tertiary-butyl-ether (MTBE and the biomass burning marker acetonitrile (CH₃CN, we show that a combination of industrial, evaporative fuel, and exhaust emissions account for >87% of all BTEX sources. Our observations suggest that biomass burning emissions play a minor role for the abundance of BTEX compounds in the MCMA (2–13%.

Low-temperature field evaporation of Nb3Sn compound

International Nuclear Information System (INIS)

Ksenofontov, V.A.; Kul'ko, V.B.; Kutsenko, P.A.

1986-01-01

Investigation results on field evaporation of superconducting Nb 3 Sn compound wth A15 lattice are presented. Compound evaporation is shown to proceed in two stages. Evaporation field and ionic composition of evaporating material are determined. It is found out that in strong electric fields compound surface represents niobium skeleton, wich does not form regular image. Comparison of ion-microscopic and calculated images formed by low-temperature field evaporation indicates to possibility of sample surface reconstruction after preferable tin evaporation

Standardization of Tragopogon graminifolius DC. Extract Based on Phenolic Compounds and Antioxidant Activity

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Mohammad Hosein Farzaei

2014-01-01

Full Text Available Tragopogon graminifolius DC. (TG, Compositae family, is traditionally used for the treatment of various diseases like gastrointestinal and hepatic disorders. The aim of the present study is to standardize extracts from TG used for preparation of different dosage forms in traditional Iranian medicine (TIM based on phenolic compounds. For this purpose, total phenolic content and some phenolic compounds were determined in ethanolic extracts from aerial part and root of TG by HPLC method. Furthermore, antioxidant activity was evaluated using DPPH-HPLC methods. Caffeic acid, gallic acid, ρ-coumaric acid, ferulic acid, and catechin were detected in root and aerial part of TG. ρ-Coumaric acid (6.357 ± 0.014 mg·g−1 was dominant phenolic compound in aerial part followed by ferulic acid (1.24 ± 0.018 mg·g−1. Also, ρ-coumaric acid (2.685 ± 0.031 mg·g−1 was highly abundant in root, followed by catechin (2.067 ± 0.021 mg·g−1. Antioxidant activity of root extract (460.45 ± 0.78 µg Vit.E.E·mL−1 was better than that of aerial part. Generally, phenolic compounds are one of the major constituents of TG and could be used as markers for standardization of dosage forms prepared from this plant. Also, TG demonstrated significant antioxidant activity using DPPH-HPLC method. Phenolic compounds of TG may be responsible for its marked antioxidant properties.

Synthesis and NMR characterization of ( sup 15 N)taurine (2-( sup 15 N)aminoethanesulfonic acid)

Energy Technology Data Exchange (ETDEWEB)

Philippossian, G.; Welti, D.H.; Fumeaux, R.; Richli, U.; Anantharaman, K. (Nestle Research Centre, Nestec Ltd., Lausanne (Switzerland))

1989-11-01

The title compound was prepared in three steps with 55% overall yield starting from potassium ({sup 15}N)phthalimide. The synthetic route involved reaction with 1,2-dibromoethane, hydrolysis of the resulting N-(2-bromoethyl) ({sup 15}N)phthalimide with HBr and treatment of the 2-bromoethyl({sup 15}N)amine thus formed with sodium sulphite. The product was characterized by {sup 13}C, {sup 1}H and {sup 15}N NMR spectroscopy. The absolute coupling constants of {sup 15}N with the {sup 13}C nuclei and the non-exchanging protons were determined and an unambiguous assignment of the proton signals obtained. (author).

Carbon Nanomaterials Based Electrochemical Sensors/Biosensors for the Sensitive Detection of Pharmaceutical and Biological Compounds

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Bal-Ram Adhikari

2015-09-01

Full Text Available Electrochemical sensors and biosensors have attracted considerable attention for the sensitive detection of a variety of biological and pharmaceutical compounds. Since the discovery of carbon-based nanomaterials, including carbon nanotubes, C60 and graphene, they have garnered tremendous interest for their potential in the design of high-performance electrochemical sensor platforms due to their exceptional thermal, mechanical, electronic, and catalytic properties. Carbon nanomaterial-based electrochemical sensors have been employed for the detection of various analytes with rapid electron transfer kinetics. This feature article focuses on the recent design and use of carbon nanomaterials, primarily single-walled carbon nanotubes (SWCNTs, reduced graphene oxide (rGO, SWCNTs-rGO, Au nanoparticle-rGO nanocomposites, and buckypaper as sensing materials for the electrochemical detection of some representative biological and pharmaceutical compounds such as methylglyoxal, acetaminophen, valacyclovir, β-nicotinamide adenine dinucleotide hydrate (NADH, and glucose. Furthermore, the electrochemical performance of SWCNTs, rGO, and SWCNT-rGO for the detection of acetaminophen and valacyclovir was comparatively studied, revealing that SWCNT-rGO nanocomposites possess excellent electrocatalytic activity in comparison to individual SWCNT and rGO platforms. The sensitive, reliable and rapid analysis of critical disease biomarkers and globally emerging pharmaceutical compounds at carbon nanomaterials based electrochemical sensor platforms may enable an extensive range of applications in preemptive medical diagnostics.

Elastic constants of a Laves phase compound: C15 NbCr{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Ormeci, A. [Koc Univ., Istanbul (Turkey)]|[Los Alamos National Lab., NM (United States); Chu, F.; Wills, J.M.; Chen, S.P.; Albers, R.C.; Thoma, D.J.; Mitchell, T.E. [Los Alamos National Lab., NM (United States)

1997-04-01

The single-crystal elastic constants of C15 NbCr{sub 2} have been computed by using a first-principles, self-consistent, full-potential total energy method. From these single-crystal elastic constants the isotropic elastic moduli are calculated using the Voigt and Reuss averages. The calculated values are in fair agreement with the experimental values. The implications of the results are discussed with regards to Poisson`s ratio and the direction dependence of Young`s modulus.

Synthesis, characterization, antimicrobial screening and computational studies of 4-[3-(4-methoxy-phenyl)-allylideneamino]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one

Science.gov (United States)

Obasi, L. N.; Kaior, G. U.; Rhyman, L.; Alswaidan, Ibrahim A.; Fun, Hoong-Kun; Ramasami, P.

2016-09-01

The Schiff base, 4-[3-(4-methoxy-phenyl)-allylideneamino]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (TPMC/AAP) was synthesized by the condensation of 4-aminoantipyrine (4-amino-1,5-dimethyl-2-phenylpyrazole-3-one) and trans-para-methoxycinnamaldehyde (trans-3,4-methoxyphenyl-2-propenal) in dry methanol at 75 °C. The compound was characterized using elemental microanalysis, IR, NMR, UV spectroscopies and single-crystal X-ray crystallography. The X-ray structure determination shows that the Schiff base, (TPMC/AAP) is orthorhombic with the Pbca space group. The anti-microbial screening of the compound was carried out with Escherichia coli, Bacillus subtillis, Staphylococcus aureus, Pseudemonas aeruginosa, Candida albicans and Aspergillus niger using agar well diffusion method. The Schiff base possesses significant antimicrobial activity. The minimum inhibitory concentration (MIC) of the compound was also determined and the activity was compared with that of conventional drugs ciprofloxacin and ketoconazole. The compound (TPMC/AAP) showed varying activity against the cultured bacteria and fungi used. To complement the experimental data, density functional theory (DFT) was used to have deeper understanding into the molecular parameters and infrared spectra of the compound.

Facile synthesis and antimicrobial evaluation of some new heterocyclic compounds incorporating a biologically active sulfamoyl moiety.

Science.gov (United States)

Darwish, Elham S

2014-01-01

A facile and convenient synthesis of new heterocyclic compounds containing a sulfamoyl moiety suitable for use as antimicrobial agents was reported. The precursor 3-oxo-3-phenyl-N-(4-sulfamoylphenyl)propionamide was coupled smoothly with arenediazonium salt producing hydrazones which reacted with malononitrile or triethylorthoformate affording pyridazine and triazine derivatives, respectively. Also, the reactivity of the same precursor with DMF-DMA was followed by aminotriazole; aromatic aldehydes was followed by hydrazine hydrate, triethylorthoformate, or thiourea affording triazolo[1,5-a]pyrimidine, pyrazole, acrylamide, and dihydropyrimidine derivatives, respectively. On the other hand, treatment of the precursor propionamide with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt which was treated with dilute HCl followed by 2-bromo-1-phenylethanone affording carboxamide derivative. While the same intermediate salt reacted in situ with chloroacetone, ethyl 2-chloroacetate, 3-(2-bromoacetyl)-2H-chromen-2-one, methyl iodide, or 2-oxo-N-phenylpropane hydrazonoyl chloride afforded the thiophene, ketene N,S-acetal, and thiadiazole derivatives, respectively. The structure of the new products was established based on elemental and spectral analysis. Antimicrobial evaluation of some selected examples from the synthesized products was carried out whereby four compounds were found to have moderate activities and one compound showed the highest activity.

Nanostructured Polypyrrole-Based Ammonia and Volatile Organic Compound Sensors

Directory of Open Access Journals (Sweden)

Milena Šetka

2017-03-01

Full Text Available The aim of this review is to summarize the recent progress in the fabrication of efficient nanostructured polymer-based sensors with special focus on polypyrrole. The correlation between physico-chemical parameters, mainly morphology of various polypyrrole nanostructures, and their sensitivity towards selected gas and volatile organic compounds (VOC is provided. The different approaches of polypyrrole modification with other functional materials are also discussed. With respect to possible sensors application in medicine, namely in the diagnosis of diseases via the detection of volatile biomarkers from human breath, the sensor interaction with humidity is described as well. The major attention is paid to analytes such as ammonia and various alcohols.

Compound-complex odontoma: A case report of a rare variant

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Nishath Khanum

2014-01-01

Full Text Available The odontoma is a benign tumor containing all the various component tissues of the teeth. It is the most common odontogenic tumor representing 67% of all odontogenic tumors. Odontomas are considered to be developmental anomalies (hamartomas rather than true neoplasms. Based on the degree of morphodifferentiation or on the basis of their resemblance to normal teeth, they are divided into compound and complex odontomas. The compound odontoma is composed of multiple, small tooth-like structures. The complex odontoma consists of a conglomerate mass of enamel and dentin, which bears no anatomic resemblance to a tooth. They are usually diagnosed on routine radiological examinations in the second decade of life and are often slow growing and non-aggressive in nature. Here, we report a case of rare, unusually large, compound-complex odontoma, located in the left anterior maxilla of a 13-year-old male patient.

Compound cueing in free recall

Science.gov (United States)

Lohnas, Lynn J.; Kahana, Michael J.

2013-01-01

According to the retrieved context theory of episodic memory, the cue for recall of an item is a weighted sum of recently activated cognitive states, including previously recalled and studied items as well as their associations. We show that this theory predicts there should be compound cueing in free recall. Specifically, the temporal contiguity effect should be greater when the two most recently recalled items were studied in contiguous list positions. A meta-analysis of published free recall experiments demonstrates evidence for compound cueing in both conditional response probabilities and inter-response times. To help rule out a rehearsal-based account of these compound cueing effects, we conducted an experiment with immediate, delayed and continual-distractor free recall conditions. Consistent with retrieved context theory but not with a rehearsal-based account, compound cueing was present in all conditions, and was not significantly influenced by the presence of interitem distractors. PMID:23957364

Compound cuing in free recall.

Science.gov (United States)

Lohnas, Lynn J; Kahana, Michael J

2014-01-01

According to the retrieved context theory of episodic memory, the cue for recall of an item is a weighted sum of recently activated cognitive states, including previously recalled and studied items as well as their associations. We show that this theory predicts there should be compound cuing in free recall. Specifically, the temporal contiguity effect should be greater when the 2 most recently recalled items were studied in contiguous list positions. A meta-analysis of published free recall experiments demonstrates evidence for compound cuing in both conditional response probabilities and interresponse times. To help rule out a rehearsal-based account of these compound cuing effects, we conducted an experiment with immediate, delayed, and continual-distractor free recall conditions. Consistent with retrieved context theory but not with a rehearsal-based account, compound cuing was present in all conditions, and was not significantly influenced by the presence of interitem distractors.

Bioavailability of dietary phenolic compounds: Review

Directory of Open Access Journals (Sweden)

Erick Gutiérrez-Grijalva Paul Gutiérrez-Grijalva

2015-12-01

Full Text Available Phenolic compounds are ubiquitous in plant-based foods. High dietary intake of fruits, vegetables and cereals is related to a decreased rate in chronic diseases. Phenolic compounds are thought to be responsible, at least in part, for those health effects. Nonetheless, phenolic compounds bioaccessibility and biotransformation is often not considered in these studies; thus, a precise mechanism of action of phenolic compounds is not known. In this review we aim to present a comprehensive knowledge of the metabolic processes through which phenolic compounds go after intake.

Leaching characteristics of calcium-based compounds in MSWI Residues: From the viewpoint of clogging risk

Energy Technology Data Exchange (ETDEWEB)

Xia, Yi [State Key Laboratory of Pollution Control & Resource Reuse, Tongji University, Shanghai 200092 (China); Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092 (China); Zhang, Hua, E-mail: zhanghua_tj@tongji.edu.cn [State Key Laboratory of Pollution Control & Resource Reuse, Tongji University, Shanghai 200092 (China); Phoungthong, Khamphe [State Key Laboratory of Pollution Control & Resource Reuse, Tongji University, Shanghai 200092 (China); Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092 (China); Shi, Dong-Xiao; Shen, Wen-Hui [Changzhou Domestic Waste Treatment Center, Changzhou 213000 (China); Shao, Li-Ming [Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092 (China); Center for the Technology Research and Training on Household Waste in Small Towns & Rural Area, Ministry of Housing and Urban–Rural Development of PR China (MOHURD), Shanghai 200092 (China); He, Pin-Jing, E-mail: solidwaste@tongji.edu.cn [Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092 (China); Center for the Technology Research and Training on Household Waste in Small Towns & Rural Area, Ministry of Housing and Urban–Rural Development of PR China (MOHURD), Shanghai 200092 (China)

2015-08-15

Highlights: • The leaching behavior of Ca-based compounds commonly in MSWI residues was studied. • pH is the crucial factor for calcium leaching process. • CaCO{sub 3} was the most sensitive to leaching temperature and Ca{sub 3}(PO{sub 4}){sub 2} was the least. • Ca leaching of MSWIBA and SAPCR attributed to CaCO{sub 3} and Ca{sub 3}(PO{sub 4}){sub 2} respectively. • Potential clogging ability of MSWI residues leachate in open air was calculated. - Abstract: Leachate collection system (LCS) clogging caused by calcium precipitation would be disadvantageous to landfill stability and operation. Meanwhile, calcium-based compounds are the main constituents in both municipal solid waste incineration bottom ash (MSWIBA) and stabilized air pollution control residues (SAPCR), which would increase the risk of LCS clogging once these calcium-rich residues were disposed in landfills. The leaching behaviors of calcium from the four compounds and municipal solid waste incineration (MSWI) residues were studied, and the influencing factors on leaching were discussed. The results showed that pH was the crucial factor in the calcium leaching process. CaCO{sub 3} and CaSiO{sub 3} began leaching when the leachate pH decreased to less than 7 and 10, respectively, while Ca{sub 3}(PO{sub 4}){sub 2} leached at pH < 12. CaSO{sub 4} could hardly dissolve in the experimental conditions. Moreover, the sequence of the leaching rate for the different calcium-based compounds is as follows: CaSiO{sub 3} > Ca{sub 3}(PO{sub 4}){sub 2} > CaCO{sub 3}. The calcium leaching from the MSWIBA and SAPCR separately started from pH < 7 and pH < 12, resulting from CaCO{sub 3} and Ca{sub 3}(PO{sub 4}){sub 2} leaching respectively, which was proven by the X-ray diffraction results. Based on the leaching characteristics of the different calcium compounds and the mineral phase of calcium in the incineration residues, simulated computation of their clogging potential was conducted, providing the

Key volatile aroma compounds of lactic acid fermented malt based beverages - impact of lactic acid bacteria strains.

Science.gov (United States)

Nsogning Dongmo, Sorelle; Sacher, Bertram; Kollmannsberger, Hubert; Becker, Thomas

2017-08-15

This study aims to define the aroma composition and key aroma compounds of barley malt wort beverages produced from fermentation using six lactic acid bacteria (LAB) strains. Gas chromatography mass spectrometry-olfactometry and flame ionization detection was employed; key aroma compounds were determined by means of aroma extract dilution analysis. Fifty-six detected volatile compounds were similar among beverages. However, significant differences were observed in the concentration of individual compounds. Key aroma compounds (flavor dilution (FD) factors ≥16) were β-damascenone, furaneol, phenylacetic acid, 2-phenylethanol, 4-vinylguaiacol, sotolon, methional, vanillin, acetic acid, nor-furaneol, guaiacol and ethyl 2-methylbutanoate. Furthermore, acetaldehyde had the greatest odor activity value of up to 4266. Sensory analyses revealed large differences in the flavor profile. Beverage from L. plantarum Lp. 758 showed the highest FD factors in key aroma compounds and was correlated to fruity flavors. Therefore, we suggest that suitable LAB strain selection may improve the flavor of malt based beverages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthesis and crystal structure of Fe[(Te1.5Se0.5)O5]Cl, the first iron compound with selenate(IV) and tellurate(IV) groups

Science.gov (United States)

Akhrorov, Akhmad Yu; Kuznetsova, Elena S.; Aksenov, Sergey M.; Berdonosov, Peter S.; Kuznetsov, Alexey N.; Dolgikh, Valery A.

2017-12-01

During the search for selenium analogues of FeTe2O5Cl, the new iron (III) tellurate(IV) selenate(IV) chloride with the composition Fe[(Te1.5Se0.5)O5]Cl was synthesized by chemical vapor transport (CVT) reaction and characterized by TGA-, EDX-,SCXRD-analysis, as well as IR and Raman spectroscopy. It was found that Fe[(Te1.5Se0.5)O5]Cl crystallizes in the monoclinic space group P21/c with unitcell parameters a = 5.183(3) Å, b = 15.521(9) Å, c = 7.128(5) Å and β = 107.16(1)°. The crystal structure of Fe[(Te1.5Se0.5)O5]Cl represents a new structure type and contains electroneutral heteropolyhedral layers formed by dimers of the [FeO5Cl]8- octahedra, linked via common O-O edges, and mixed [Te3SeO10]4- tetramers. Adjacent layers are stacked along the b axis and linked by weak residual bonds. The new compound is stable up to 420 °C. DFT calculations predict Fe[(Te1.5Se0.5)O5]Cl to be a wide-gap semiconductor with the band gap of ca. 2.7 eV.

A process-based emission model of volatile organic compounds from silage sources on farms

DEFF Research Database (Denmark)

Bonifacio, H. F.; Rotz, C. A.; Hafner, S. D.

2017-01-01

Silage on dairy farms can emit large amounts of volatile organic compounds (VOCs), a precursor in the formation of tropospheric ozone. Because of the challenges associated with direct measurements, process-based modeling is another approach for estimating emissions of air pollutants from sources...... was evaluated using ethanol and methanol emissions measured from conventional silage piles (CSP), silage bags (SB), total mixed rations (TMR), and loose corn silage (LCS) at a commercial dairy farm in central California. With transport coefficients for ethanol refined using experimental data from our previous......% if feeds were delivered as four feedings per day rather than as one. Reducing the exposed face of storage can also be useful. Simulated use of silage bags resulted in 90% and 18% reductions in emissions from the storage face and whole farm, respectively....

Novel Compound Heterozygous CLCNKB Gene Mutations (c.1755A>G/ c.848_850delTCT) Cause Classic Bartter Syndrome.

Science.gov (United States)

Wang, Chunli; Chen, Ying; Zheng, Bixia; Zhu, Mengshu; Fan, Jia; Wang, Juejin; Jia, Zhanjun; Huang, Songming; Zhang, Aihua

2018-02-14

Inactivated variants in CLCNKB gene encoding the basolateral chloride channel ClC-Kb cause classic Bartter syndrome characterized by hypokalemic metabolic alkalosis and hyperreninemic hyperaldosteronism. Here we identified two cBS siblings presenting hypokalemia in a Chinese family due to novel compound heterozygous CLCNKB mutations (c.848_850delTCT/c.1755A>G). Compound heterozygosity was confirmed by amplifying and sequencing the patient's genomic DNA. The synonymous mutation c.1755A>G (Thr585Thr) was located at +2bp from the 5' splice donor site in exon 15, further transcript analysis demonstrated that this single nucleotide mutation causes exclusion of exon 15 in the cDNA from the proband and his mother. Furthermore, we investigated the expression and protein trafficking change of c.848_850delTCT (TCT) and exon 15 deletion（E15）mutation in vitro. The E15 mutation markedly decreased the expression of ClC-Kb and resulted in a low-molecular-weight band (~55kD) trapping in the endoplasmic reticulum, while the TCT mutant only decreased the total and plasma membrane ClC-Kb protein expression but did not affect the subcellular localization. Finally, we studied the physiological functions of mutations by using whole-cell patch clamp and found that E15 or TCT mutation decreased the current of ClC-Kb/barttin channel. These results suggested that the compound defective mutations of CLCNKB gene are the molecular mechanism of the two cBS siblings.

The effect of high pressure on nitrogen compounds of milk

International Nuclear Information System (INIS)

Kielczewska, Katarzyna; Czerniewicz, Maria; Michalak, Joanna; Brandt, Waldemar

2004-01-01

The effect of pressurization at different pressures (from 200 to 1000 MPa, at 200 MPa intervals, t const. = 15 min) and periods of time (from 15 to 35 min, at 10 min intervals, p const. = 800 MPa) on the changes of proteins and nitrogen compounds of skimmed milk was studied. The pressurization caused an increase in the amount of soluble casein and denaturation of whey proteins. The level of nonprotein nitrogen compounds and proteoso-peptone nitrogen compounds increased as a result of the high-pressure treatment. These changes increased with an increase in pressure and exposure time. High-pressure treatment considerably affected the changes in the conformation of milk proteins, which was reflected in the changes in the content of proteins sedimenting and an increase in their degree of hydration

Model for fusion and cool compound nucleus formation based on the fragmentation theory

International Nuclear Information System (INIS)

Malhotra, N.; Aroumougame, R.; Saroha, D.R.; Gupta, R.K.

1986-01-01

Collective potential energy surfaces are calculated in both the adiabatic and sudden approximations by using the asymmetric two-center shell model in the Strutinsky method. It is shown that fusion of two colliding heavy ions occurs by their crossing over of the adiabatic interaction barrier. The adiabatic scattering potentials present two barriers, whereas no barrier is shown to occur in sudden scattering potentials. The first barrier is obtained just past the saddle shape but is too low, such that a deep inelastic process is expected. The other, inner, barrier is high enough to let the system fall into the fusion well, whose excitation energy then determines whether a cool compound nucleus is produced or the fusion-fission process occurs. For a given compound nucleus, the excitation energy is found to be small for only a few target-projectile combinations, which increase as their mass asymmetry increases. Such target-projectile combinations which refer to a cool compound nucleus can be identified by a simple calculation of the fragmentation potential based on the ground state binding energies with Coulomb and proximity effects calculated at a constant relative separation of the two nuclei. Our calculations are made for the composite systems with 102 < or =Z < or =114

Model for fusion and cool compound nucleus formation based on the fragmentation theory

International Nuclear Information System (INIS)

Malhotra, N.; Aroumougame, R.; Saroha, D.R.; Gupta, R.K.

1985-07-01

The collective potential energy surfaces are calculated in both the adiabatic and sudden approximations by using the asymmetric two centre shell model in Strutinsky method. It is shown that fusion of two colliding heavy ions occur by their crossing over of the adiabatic interaction barrier. The adiabatic scattering potentials present two barriers whereas no barrier is shown to occur in sudden scattering potentials. The first barrier is obtained just past the saddle shape but is too low, such that a deep inelastic process is expected. The other, inner, barrier is high enough to let the system fall into the fusion well, whose excitation energy then determine whether a cool compound nucleus is produced or the fusion-fission process occurs. For a given compound nucleus, the excitation energy is found to be small for only a few target-projectile combinations, which increase as their mass asymmetry increases. Such target-projectile combinations which refer to a cool compound nucleus, can be identified by a simple calculation of the fragmentation potential based on the ground state binding energies with Couloumb and proximity effects calculated at a constant relative separation of the two nuclei. Our calculations are made for the composite systems with 102<=Z<=114. (author)

A ranking method for the concurrent learning of compounds with various activity profiles.

Science.gov (United States)

Dörr, Alexander; Rosenbaum, Lars; Zell, Andreas

2015-01-01

In this study, we present a SVM-based ranking algorithm for the concurrent learning of compounds with different activity profiles and their varying prioritization. To this end, a specific labeling of each compound was elaborated in order to infer virtual screening models against multiple targets. We compared the method with several state-of-the-art SVM classification techniques that are capable of inferring multi-target screening models on three chemical data sets (cytochrome P450s, dehydrogenases, and a trypsin-like protease data set) containing three different biological targets each. The experiments show that ranking-based algorithms show an increased performance for single- and multi-target virtual screening. Moreover, compounds that do not completely fulfill the desired activity profile are still ranked higher than decoys or compounds with an entirely undesired profile, compared to other multi-target SVM methods. SVM-based ranking methods constitute a valuable approach for virtual screening in multi-target drug design. The utilization of such methods is most helpful when dealing with compounds with various activity profiles and the finding of many ligands with an already perfectly matching activity profile is not to be expected.

Radiation damage in A-15 materials: EXAFS studies

International Nuclear Information System (INIS)

Knapp, G.S.; Kampwirth, R.T.; Georgopoulos, P.; Brown, B.S.

1980-01-01

EXAFS measurements are useful in determining the local atomic environment of a particular element in a solid. Since there has been some controversy about the nature of the defects produced in A-15 materials by radiation damage, such studies were carried out on some A-15 compounds, V 3 Ga which was damaged by neutrons, as well as Nb 3 Ge damaged by 2.5 MeV a particles. In the V 3 Ga sample, site exchange disorder seems to be the most important result of the neutron damage with less than 20% of the vanadium atoms on wrong sites. However, in the Nb 3 Ge samples in addition to site exchange disorder, an unusual splitting of the first near-neighbor distance between the Ge and Nb is found. This splitting, approximately 0.2 A, may explain the large Debye Waller factors observed by Burbank et al

High-energy neutron irradiation of superconducting compounds

International Nuclear Information System (INIS)

Sweedler, A.R.; Snead, C.L.; Newkirk, L.; Valencia, F.; Geballe, T.H.; Schwall, R.H.; Matthias, B.T.; Corenswit, E.

1975-01-01

The effect of high-energy neutron irradiation (E greater than 1 MeV) at ambient reactor temperatures on the superconducting properties of a variety of superconducting compounds is reported. The materials studied include the A-15 compounds Nb 3 Sn, Nb 3 Al, Nb 3 Ga, Nb 3 Ge and V 3 Si, the C-15 Laves phase HfV 2 , the ternary molybdenum sulfide Mo 3 Pb 0 . 5 S 4 and the layered dichalcogenide NbSe 2 . The superconducting transition temperature has been measured for all of the above materials for neutron fluences up to 5 x 10 19 n/cm 2 . The critical current for multifilamentary Nb 3 Sn has also been determined for fields up to 16 T and fluences between 3 x 10 17 n/cm 2 and 1.1 x 10 19 n/cm 2

Estimate of consumption of phenolic compounds by Brazilian population

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Vanesa Gesser Corrêa

2015-04-01

Full Text Available OBJECTIVE: Estimate the intake of phenolic compounds by the Brazilian population. METHODS: To estimate the average per capita food consumption, micro data from the National Dietary Survey and from the Household Budget Survey from 2008 to 2009 was analyzed. The phenolic content in food was estimated from the base of Phenol-Explorer. It was chosen according to compatibility and variety of food items and usual method of preparation. RESULTS: The Brazilian population consumed, on average, 460.15 mg/day of total phenolic compounds, derived mainly from beverages (48.9%, especially coffee and legumes (19.5%. Since this analysis of classes of phenolics it was possible to observe an intake of 314 mg/day of phenolic acids, 138.92 mg/day of flavonoids and 7.16 mg/ day of other kinds of phenolics. Regarding the variables studied this present study shows that those men who live in the countryside and in the northeastern region of the country had a higher consumption of phenolic compounds. Besides, consumption was higher by adults and the elderly, the medium income classes, the population with incomplete and complete primary education and those with adequate nutrition and also overweight status. CONCLUSION: The intake of phenolic compounds can be considered low, especially where consumption of fruit and vegetables is insufficient. We can conclude that coffee and black beans were the best contributors to phenolic intake.

Synthesis, biological evaluation and molecular modeling of a novel series of 7-azaindole based tri-heterocyclic compounds as potent CDK2/Cyclin E inhibitors.

Science.gov (United States)

Baltus, Christine B; Jorda, Radek; Marot, Christophe; Berka, Karel; Bazgier, Václav; Kryštof, Vladimír; Prié, Gildas; Viaud-Massuard, Marie-Claude

2016-01-27

From four molecules, inspired by the structural features of fascaplysin, with an interesting potential to inhibit cyclin-dependent kinases (CDKs), we designed a new series of tri-heterocyclic derivatives based on 1H-pyrrolo[2,3-b]pyridine (7-azaindole) and triazole heterocycles. Using a Huisgen type [3 + 2] cycloaddition as the convergent key step, 24 derivatives were synthesized and their biological activities were evaluated. Comparative molecular field analysis (CoMFA), based on three-dimensional quantitative structure-activity relationship (3D-QSAR) studies, was conducted on a series of 30 compounds from the literature with high to low known inhibitory activity towards CDK2/cyclin E and was validated by a test set of 5 compounds giving satisfactory predictive r(2) value of 0.92. Remarkably, it also gave a good prediction of pIC50 for our tri-heterocyclic series which reinforce the validation of this model for the pIC50 prediction of external set compounds. The most promising compound, 43, showed a micro-molar range inhibitory activity against CDK2/cyclin E and also an antiproliferative and proapoptotic activity against a panel of cancer cell lines. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Potent inhibitors of human LAT1 (SLC7A5) transporter based on dithiazole and dithiazine compounds for development of anticancer drugs.

Science.gov (United States)

Napolitano, Lara; Scalise, Mariafrancesca; Koyioni, Maria; Koutentis, Panayiotis; Catto, Marco; Eberini, Ivano; Parravicini, Chiara; Palazzolo, Luca; Pisani, Leonardo; Galluccio, Michele; Console, Lara; Carotti, Angelo; Indiveri, Cesare

2017-11-01

The LAT1 transporter is acknowledged as a pharmacological target of tumours since it is strongly overexpressed in many human cancers. The purpose of this work was to find novel compounds exhibiting potent and prolonged inhibition of the transporter. To this aim, compounds based on dithiazole and dithiazine scaffold have been screened in the proteoliposome experimental model. Inhibition was tested on the antiport catalysed by hLAT1 as transport of extraliposomal [ 3 H]histidine in exchange with intraliposomal histidine. Out of 59 compounds tested, 8 compounds, showing an inhibition higher than 90% at 100µM concentration, were subjected to dose-response analysis. Two of them exhibited IC 50 lower than 1µM. Inhibition kinetics, performed on the two best inhibitors, indicated a mixed type of inhibition with respect to the substrate. Furthermore, inhibition of the transporter was still present after removal of the compounds from the reaction mixture, but was reversed on addition of dithioerythritol, a S-S reducing agent, indicating the formation of disulfide(s) between the compounds and the protein. Molecular docking of the two best inhibitors on the hLAT1 homology structural model, highlighted interaction with the substrate binding site and formation of a covalent bond with the residue C407. Indeed, the inhibition was impaired in the hLAT1 mutant C407A confirming the involvement of that Cys residue. Treatment of SiHa cells expressing hLAT1 at relatively high level, with the two most potent inhibitors led to cell death which was not observed after treatment with a compound exhibiting very poor inhibitory effect. Copyright © 2017 Elsevier Inc. All rights reserved.

A new multidimensional stoichiometric classification of compounds: moving beyond the van Krevelen diagram.

Science.gov (United States)

Rivas-Ubach, A.; Liu, Y.; Bianchi, T. S.; Tolic, N.; Jansson, C.; Paša-Tolić, L.

2017-12-01

The role of nutrients in organisms, especially primary producers, has been a topic of special interest in ecosystem research for understanding the ecosystem structure and function. The majority of macro-elements in organisms, such as C, H, O, N and P, do not act as single elements but are components of organic compounds (lipids, peptides, carbohydrates, etc), which are more directly related to the physiology of organisms and thus to the ecosystem function. However, accurately deciphering the overall content of the main compound classes (lipids, proteins, carbohydrates,…) in organisms is still a major challenge. van Krevelen (vK) diagrams have been widely used as an estimation of the main compound categories present in environmental samples based on O:C vs H:C molecular ratios, but a stoichiometric classification based exclusively on O:C and H:C ratios is feeble. Different compound classes show large O:C and H:C ratio overlapping and other heteroatoms, such as N and P, should be considered to robustly distinguish the different classes. We propose a new compound classification for biological/environmental samples based on the C:H:O:N:P stoichiometric ratios of thousands of molecular formulas of characterized compounds from 6 different main categories: lipids, peptides, amino-sugars, carbohydrates, nucleotides and phytochemical compounds (oxy-aromatic compounds). This new multidimensional stoichiometric compound constraints classification (MSCC) can be applied to data obtained with high resolution mass spectrometry (HRMS), allowing an accurate overview of the relative abundances of the main compound categories present in organismal samples. The MSCC has been optimized for plants, but it could be also applied to different organisms and serve as a strong starting point to further investigate other environmental complex matrices (soils, aerosols, etc). The proposed MSCC advances environmental research, especially eco-metabolomics, ecophysiology and ecological

II-VI semiconductor compounds

CERN Document Server

1993-01-01

For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

A new wire fabrication processing using high Ga content Cu-Ga compound in V3Ga compound superconducting wire

International Nuclear Information System (INIS)

Hishinuma, Yoshimitsu; Nishimura, Arata; Kikuchi, Akihiro; Iijima, Yasuo; Takeuchi, Takao

2007-01-01

A superconducting magnet system is also one of the important components in an advanced magnetic confinement fusion reactor. Then it is required to have a higher magnetic field property to confine and maintain steady-sate burning deuterium (D)-tritium (T) fusion plasma in the large interspace during the long term operation. Burning plasma is sure to generate 14 MeV fusion neutrons during deuterium-tritium reaction, and fusion neutrons will be streamed and penetrated to superconducting magnet through large ports with damping neutron energy. Therefore, it is necessary to consider carefully not only superconducting property but also neutron irradiation property in superconducting materials for use in a future fusion reactor, and a 'low activation and high field superconducting magnet' will be required to realize the fusion power plant beyond International Thermonuclear Experimental Reactor (ITER). V-based superconducting material has a much shorter decay time of induced radioactivity compared with the Nb-based materials. We thought that the V 3 Ga compound was one of the most promising materials for the 'low activation and higher field superconductors' for an advanced fusion reactor. However, the present critical current density (J c ) property of V 3 Ga compound wire is insufficient for apply to fusion magnet applications. We investigated a new route PIT process using a high Ga content Cu-Ga compound in order to improve the superconducting property of the V 3 Ga compound wire. (author)

Preparation and studying acid - base properties of the compound a -mono thiosemicarbazide isatin-5-Sodium sulfonate (α-MTI-5-SO3Na)

International Nuclear Information System (INIS)

Al-Azrak, A.

2015-01-01

This research aims to prepare organic compounds containing functional groups and have analytical properties to use as analytical reagents for determination of metal ions by spectrophotometric methods as acid-base indicators and as indicators for metal ions in EDTA titrations in this paper was prepared the compound ((α-mono thiosemicarbazide isatien -5-sodium sulfonate) it showed analytical properties and significant practical applications this compound has in acidic medium yellow color while in the basic medium sharply changes its color to red color the value of pKa of this compound has been calculated by spectrophotometric method and was equal to (8.860±0.054) the pH transition range was between (8.20 to 9.8) the indicator was used for determination the end point of the titration standard samples of solution (0.1M, NaOH) with standard solution of 0.1M, HCI, and in titration standard samples of solution (0.1M, CH 3 COOH) with standard solution of 0.1M NaOH the results were compared with the results obtained by reference titrimetric methods the statistical treatment for allresults shows that the end point determination using acid - base ((α-MTI-5-SO 3 Na) is the most accurate. (author)

Thermohydraulic performance comparision of compound inserts for a turbulent flow through a circular tube

Directory of Open Access Journals (Sweden)

Kapse Arvind A.

2017-01-01

Full Text Available Heat transfer and pressure drop characteristics of three different passive inserts are experimentally investigated for individual and compound insertion. Insert cross-section is altered along the length of test section for compound insertion. Test runs were conducted in a concentric circular tube in tube heat exchanger in the Reynolds number range of 8000 to 32000 with water as a working fluid. Enhancements in Nusselt number and friction factors are reported to be in the range of 38-234% and 55-524%, respectively, over plain tube. The average performance ratios based on equal pumping power are also reported and found in the range of 0.63-1.53. Based on experimental results, optimum combination for compound insertion is proposed.

Rapid countermeasure discovery against Francisella tularensis based on a metabolic network reconstruction.

Directory of Open Access Journals (Sweden)

Sidhartha Chaudhury

Full Text Available In the future, we may be faced with the need to provide treatment for an emergent biological threat against which existing vaccines and drugs have limited efficacy or availability. To prepare for this eventuality, our objective was to use a metabolic network-based approach to rapidly identify potential drug targets and prospectively screen and validate novel small-molecule antimicrobials. Our target organism was the fully virulent Francisella tularensis subspecies tularensis Schu S4 strain, a highly infectious intracellular pathogen that is the causative agent of tularemia and is classified as a category A biological agent by the Centers for Disease Control and Prevention. We proceeded with a staggered computational and experimental workflow that used a strain-specific metabolic network model, homology modeling and X-ray crystallography of protein targets, and ligand- and structure-based drug design. Selected compounds were subsequently filtered based on physiological-based pharmacokinetic modeling, and we selected a final set of 40 compounds for experimental validation of antimicrobial activity. We began screening these compounds in whole bacterial cell-based assays in biosafety level 3 facilities in the 20th week of the study and completed the screens within 12 weeks. Six compounds showed significant growth inhibition of F. tularensis, and we determined their respective minimum inhibitory concentrations and mammalian cell cytotoxicities. The most promising compound had a low molecular weight, was non-toxic, and abolished bacterial growth at 13 µM, with putative activity against pantetheine-phosphate adenylyltransferase, an enzyme involved in the biosynthesis of coenzyme A, encoded by gene coaD. The novel antimicrobial compounds identified in this study serve as starting points for lead optimization, animal testing, and drug development against tularemia. Our integrated in silico/in vitro approach had an overall 15% success rate in terms of

The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors.

Science.gov (United States)

Akwi, Faith M; Watts, Paul

2016-01-01

In this paper, a micro-fluidic optimized process for the continuous flow synthesis of azo compounds is presented. The continuous flow synthesis of Sudan II azo dye was used as a model reaction for the study. At found optimal azo coupling reaction temperature and pH an investigation of the optimum flow rates of the reactants for the diazotization and azo coupling reactions in Little Things Factory-MS microreactors was performed. A conversion of 98% was achieved in approximately 2.4 minutes and a small library of azo compounds was thus generated under these reaction conditions from couplers with aminated or hydroxylated aromatic systems. The scaled up synthesis of these compounds in PTFE tubing (i.d. 1.5 mm) was also investigated, where good reaction conversions ranging between 66-91% were attained.

Calcium carboorthovanadate - a new compound with the apa

International Nuclear Information System (INIS)

Slobodin, B.V.; Dmitrieva, O.I.; Fotiev, A.A.

1977-01-01

Data on calcium carboorthovanadate, Ca 10 (VO 4 ) 6 CO 3 , a new compound with an appatite structure based on calcium orthovanadate, are reported. The synthesis has been conducted in a stoichiometric mixture of finely ground calcium carbonate and calcium orthovanadate. It is found that calcium carboorthovanadate belongs to the hexagonal syngony and has an apatite structure. An analysis of the infrared spectra of initial compounds and calcium carboorthovanadate confirmed the presence of carbonate (CO 3 ) 2- and orthovanadate (VO 4 ) 3 groupings in the latter. On heating in air, beginning with 450 deg C calcium carboorthovanadate decomposes at a slow rate into calcium oxide, calcium orthovanadate, and carbon dioxide

A two-stage extraction procedure for insensitive munition (IM) explosive compounds in soils.

Science.gov (United States)

Felt, Deborah; Gurtowski, Luke; Nestler, Catherine C; Johnson, Jared; Larson, Steven

2016-12-01

The Department of Defense (DoD) is developing a new category of insensitive munitions (IMs) that are more resistant to detonation or promulgation from external stimuli than traditional munition formulations. The new explosive constituent compounds are 2,4-dinitroanisole (DNAN), nitroguanidine (NQ), and nitrotriazolone (NTO). The production and use of IM formulations may result in interaction of IM component compounds with soil. The chemical properties of these IM compounds present unique challenges for extraction from environmental matrices such as soil. A two-stage extraction procedure was developed and tested using several soil types amended with known concentrations of IM compounds. This procedure incorporates both an acidified phase and an organic phase to account for the chemical properties of the IM compounds. The method detection limits (MDLs) for all IM compounds in all soil types were regulatory risk-based Regional Screening Level (RSL) criteria for soil proposed by the U.S. Army Public Health Center. At defined environmentally relevant concentrations, the average recovery of each IM compound in each soil type was consistent and greater than 85%. The two-stage extraction method decreased the influence of soil composition on IM compound recovery. UV analysis of NTO established an isosbestic point based on varied pH at a detection wavelength of 341 nm. The two-stage soil extraction method is equally effective for traditional munition compounds, a potentially important point when examining soils exposed to both traditional and insensitive munitions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis and Anti-Bacterial Activities of Some Novel Schiff Bases Derived from Aminophenazone

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Salman A Khan

2010-10-01

Full Text Available A series of 1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one-containing Schiff bases were synthesized, characterized and screened for their antibacterial activities. The structures of the synthesized compounds were established by spectroscopic (FT-IR, 1H-NMR, 13C-NMR, MS and elemental analyses. The anti-bacterial activities (with MIC values of compounds were evaluated. The anti-bacterial screening results reveal that among the six compounds screened, four compounds showed moderate to good anti-bacterial activity. Among the tested compounds, the most effective compounds against four bacterial strains, viz. Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Streptococcus pyogenes, are [(2-Chlorobenzylideneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one (4 and [(1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yliminomethyl]benzonitrile (5 with MIC values of 6.25 μg/mL.

A study on the thermal decomposition behavior of derivatives of 1,5-diamino-1H-tetrazole (DAT): A new family of energetic heterocyclic-based salts

International Nuclear Information System (INIS)

Fischer, Gerd; Holl, Gerhard; Klapoetke, Thomas M.; Weigand, Jan J.

2005-01-01

The thermal decomposition of the highly energetic 1,5-diamino-4-methyl-1H-tetrazolium nitrate (2b), 1,5-diamino-4-methyl-1H-tetrazolium dinitramide (2c) and 1,5-diamino-4-methyl-1H-tetrazolium azide (2d) were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Mass spectrometry and IR spectroscopy were used to identify the gaseous products. Decomposition appears in the cases of 2c and 2d to be initiated by a proton transfer to form the corresponding acid HN 3 and HN 3 O 4 whereas in the case of 2b a methyl group transfer to MeONO 2 is observed as initial process. The gaseous products after the exothermic decomposition are comparable and are in agreement of the possible decomposition pathways discussed for the corresponding compounds. For all processes, possible decomposition schemes are presented. The decomposition temperatures of 2b and 2c are significantly higher than that of 2d and were supported by evaluation the values of the activation energy according the method of Ozawa and Kissinger

Poly(lactic-co-glycolic) Acid/Solutol HS15-Based Nanoparticles for Docetaxel Delivery.

Science.gov (United States)

Cho, Hyun-Jong; Park, Ju-Hwan; Kim, Dae-Duk; Yoon, In-Soo

2016-02-01

Docetaxel (DCT) is one of anti-mitotic chemotherapeutic agents and has been used for the treatment of gastric cancer as well as head and neck cancer, breast cancer and prostate cancer. Poly(lactic- co-glycolic) acid (PLGA) is one of representative biocompatible and biodegradable polymers, and polyoxyl 15 hydroxystearate (Solutol HS15) is a nonionic solubilizer and emulsifying agent. In this investigation, PLGA/Solutol HS15-based nanoparticles (NPs) for DCT delivery were fabricated by a modified emulsification-solvent evaporation method. PLGA/Solutol HS15/DCT NPs with about 169 nm of mean diameter, narrow size distribution, negative zeta potential, and spherical morphology were prepared. The results of solid-state studies revealed the successful dispersion of DCT in PLGA matrix and its amorphization during the preparation process of NPs. According to the result of in vitro release test, emulsifying property of Solutol HS15 seemed to contribute to the enhanced drug release from NPs at physiological pH. All these findings imply that developed PLGA/Solutol HS15-based NP can be a promising local anticancer drug delivery system for cancer therapy.

Compound parabolic concentrator optical fiber tip for FRET-based fluorescent sensors

DEFF Research Database (Denmark)

Hassan, Hafeez Ul; Nielsen, Kristian; Aasmul, Soren

2015-01-01

The Compound Parabolic Concentrator (CPC) optical fiber tip shape has been proposed for intensity based fluorescent sensors working on the principle of FRET (Förster Resonance Energy Transfer). A simple numerical Zemax model has been used to optimize the CPC tip geometry for a step-index multimode...... polymer optical fiber for an excitation and emission wavelength of 550 nm and 650nm, respectively. The model suggests an increase of a factor of 1.6 to 4 in the collected fluorescent power for an ideal CPC tip, as compared to the plane-cut fiber tip for fiber lengths between 5 and 45mm...

Synthesis, characterization, and properties of peroxo-based oxygen-rich compounds for potential use as greener high energy density materials

Science.gov (United States)

Gamage, Nipuni-Dhanesha Horadugoda

One main aspect of high energy density material (HEDM) design is to obtain greener alternatives for HEDMs that produce toxic byproducts. Primary explosives lead azide, lead styphnate, and mercury fulminate contain heavy metals that cause heavy metal poisoning. Leaching of the widely used tertiary explosive NH4ClO4 into groundwater has resulted in human exposure to ClO4-- ions, which cause disruptions of thyroid related metabolic pathways and even thyroid cancer. Many research efforts to find replacements have gained little success. Thus, there is a need for greener HEDMs. Peroxo-based oxygen-rich compounds are proposed as a potential new class of greener HEDMs due to the evolution of CO2 and/or CO, H2O, and O 2 as the main decomposition products. Currently, triacetone triperoxide (TATP), diacetone diperoxide (DADP), hexamethylene triperoxide diamine (HMTD), and methyl ethyl ketone peroxide (MEKP) are the only well-studied highly energetic peroxides. However, due to their high impact and friction sensitivities, low thermal stabilities, and low detonation velocities they have not found any civil or military HEDM applications. In this dissertation research, we have synthesized and fully characterized four categories of peroxo-based compounds: tert-butyl peroxides, tert-butyl peroxy esters, hydroperoxides, and peroxy acids to perform a systematic study of their sensitivities and the energetic properties for potential use as greener HEDMs. tert-Butyl peroxides were not sensitive to impact, friction, or electrostatic spark. Hence, tert-butyl peroxides can be described as fairly safe peroxo-based compounds to handle. tert-Butyl peroxy esters were all surprisingly energetic (4896--6003 m/s), despite the low oxygen and nitrogen contents. Aromatic tert -butyl peroxy esters were much lower in impact and friction sensitivities with respect to the known peroxo-based explosives. These are among the first low sensitivity peroxo-based compounds that can be categorized as secondary

Lithium insertion in the two crystallographic forms of the binary-phase Mo15Se19

Science.gov (United States)

Tarascon, J. M.; Murphy, D. W.

1986-02-01

Compounds which can undergo topotactic insertion of lithium are of potential technological importance in secondary lithium batteries. In this paper we present the chemical and electrochemical insertion of lithium into the binary-phase Mo15Se19, which can exist in two crystallographic forms, denoted AA and BB, when prepared from In3Mo15Se19 and In2Mo15Se19, respectively. We show that both forms can reversibly accommodate up to eight lithium atoms, yielding two new series of compounds of formula LixMo15Se19. This behavior is consistent with the electronic structure of the host material predicted from band-structure calculations. The room-temperature phase diagram of both LixMo15Se19 systems as a function of x has been established using electrochemical test cells (based on Mo15Se19 as the cathode), and in situ x-ray measurements as the cells discharge. Both LixMo15Se19 systems contain three single-phase domains as a function of x: two hexagonal phases and an orthorhombic phase. The nature of the transitions between these single phases and the variation of the lattice parameters within a single-phase domain are reported. While the mechanism of intercalation of lithium is similar for both Mo15Se19 forms, there is a drastic difference in Li intercalation behavior for the parent indium phases In2Mo15Se19 and In3Mo15Se19. We found that In2Mo15Se19 can reversibly incorporate 6.4 lithium atoms while In3Mo15Se19 does not react. This behavior is explained on the basis of structural considerations.

The Synthesis and Crystal Structure of Two New Hydrazone Compounds

Directory of Open Access Journals (Sweden)

Li-Hua Wang

2016-05-01

Full Text Available Two new hydrazone compounds, 4-formylimidazole-4-hydroxybenzhydrazone dihydrate (1 and 2-nitrobenzaldehyde-2-furan formylhydrazone (2, were synthesized via the classical synthesis method. Their structure was determined via elemental analysis and X-ray single crystal diffraction analysis. Compound 1 crystallizes in triclinic, space group P-1 with a = 7.0321(14 Å, b = 7.3723(15 Å, c = 13.008(3 Å, α = 98.66(3°, β = 101.69(3°, γ = 92.25(3°, V = 651.2(2 Å3, Z = 2, Dc = 1.358 g·cm−3, μ = 0.106 mm−1, F(000 = 280, and final R1 = 0.0564, ｗR2 = 0.1420. Compound 2 crystallizes in monoclinic, space group P21/c with a = 17.3618(9 Å, b = 9.1506(4 Å, c = 15.5801(7 Å, β = 104.532(5°, V = 2396.05(19 Å3, Z = 8, Dc = 1.437 g·cm−3, μ = 0.111 mm−1, F(000 = 1072, and final R1 = 0.0633, wR2 = 0.1649. Compound 1 forms a 2D-layered structure via the interactions of 1D chains and Compound 2 forms a 3D network structure via the interactions of 1D chains.

Low-temperature heat capacity and the standard molar enthalpy of formation of compound chromium(III) tri(pyrazine-2-carboxylate)

International Nuclear Information System (INIS)

Gao, Shengli; Zhang, Sheng; Chen, Sanping; Yang, Desuo

2012-01-01

Highlights: ► Low-temperature heat capacities of chromium(III) tri(pyrazine-2-carboxylate) were measured from 78 to 400 K. ► Thermodynamic functions of the compound at 298.15 K were calculated based on low-temperature heat capacity. ► The standard molar enthalpy of formation of the target was determined to be −1207.86 ± 3.39 kJ mol −1 through a designed thermochemical cycle. - Abstract: Low-temperature heat capacities of the coordination compound, chromium(III) tri(pyrazine-2-carboxylate), formulated as Cr(pyza) 3 (pyza = pyrazine-2-carboxylate), were measured by a precision automated adiabatic calorimeter over the temperature range of 78–400 K. A polynomial equation of heat capacities as a function of the temperature was fitted by the least square method. Based on the fitted polynomial equation, the fitted heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated at the interval of 5 K. In accordance with a reasonable thermochemical cycle designed, the standard molar enthalpy of formation of the title complex was determined to be −1207.86 ± 3.39 kJ mol −1 by an isoperibol solution–reaction calorimeter.

Reactivity of selenium-containing compounds with myeloperoxidase-derived chlorinating oxidants

DEFF Research Database (Denmark)

Carroll, Luke; Pattison, David I.; Fu, Shanlin

2015-01-01

and N-chloramines, causes damage to host tissue. Low molecular mass thiol compounds, including glutathione (GSH) and methionine (Met), have demonstrated efficacy in scavenging MPO-derived oxidants, which prevents oxidative damage in vitro and ex vivo. Selenium species typically have greater reactivity...... compounds (selenomethionine, methylselenocysteine, 1,4-anhydro-4-seleno-L-talitol, 1,5-anhydro-5-selenogulitol) studied. In general, selenomethionine was the most reactive with N-chloramines (k2 0.8-3.4×10(3)M(-1) s(-1)) with 1,5-anhydro-5-selenogulitol and 1,4-anhydro-4-seleno-L-talitol (k2 1.1-6.8×10(2)M......(-1) s(-1)) showing lower reactivity. This resulted in the formation of the respective selenoxides as the primary oxidation products. The selenium compounds demonstrated greater ability to remove protein N-chloramines compared to the analogous sulfur compounds. These reactions may have implications...

Zebrafish-Based Discovery of Antiseizure Compounds from the Red Sea: Pseurotin A2 and Azaspirofuran A.

Science.gov (United States)

Copmans, Daniëlle; Rateb, Mostafa; Tabudravu, Jioji N; Pérez-Bonilla, Mercedes; Dirkx, Nina; Vallorani, Riccardo; Diaz, Caridad; Pérez Del Palacio, José; Smith, Alan J; Ebel, Rainer; Reyes, Fernando; Jaspars, Marcel; de Witte, Peter A M

2018-04-19

In search for novel antiseizure drugs (ASDs), the European FP7-funded PharmaSea project used zebrafish embryos and larvae as a drug discovery platform to screen marine natural products to identify promising antiseizure hits in vivo for further development. Within the framework of this project, seven known heterospirocyclic γ-lactams, namely, pseurotin A, pseurotin A 2 , pseurotin F1, 11- O-methylpseurotin A, pseurotin D, azaspirofuran A, and azaspirofuran B, were isolated from the bioactive marine fungus Aspergillus fumigatus, and their antiseizure activity was evaluated in the larval zebrafish pentylenetetrazole (PTZ) seizure model. Pseurotin A 2 and azaspirofuran A were identified as antiseizure hits, while their close chemical analogues were inactive. Besides, electrophysiological analysis from the zebrafish midbrain demonstrated that pseurotin A 2 and azaspirofuran A also ameliorate PTZ-induced epileptiform discharges. Next, to determine whether these findings translate to mammalians, both compounds were analyzed in the mouse 6 Hz (44 mA) psychomotor seizure model. They lowered the seizure duration dose-dependently, thereby confirming their antiseizure properties and suggesting activity against drug-resistant seizures. Finally, in a thorough ADMET assessment, pseurotin A 2 and azaspirofuran A were found to be drug-like. Based on the prominent antiseizure activity in both species and the drug-likeness, we propose pseurotin A 2 and azaspirofuran A as lead compounds that are worth further investigation for the treatment of epileptic seizures. This study not only provides the first evidence of antiseizure activity of pseurotins and azaspirofurans, but also demonstrates the value of the zebrafish model in (marine) natural product drug discovery in general, and for ASD discovery in particular.

Mechanochemical synthesis of organic compounds and composites with their participation

Energy Technology Data Exchange (ETDEWEB)

Lyakhov, Nikolai Z; Grigorieva, Tatiana F; Barinova, Antonina P; Vorsina, I A [Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

2010-05-13

The results of experimental studies in the mechanochemical synthesis of organic compounds and composites with their participation published over the last 15 years are described systematically. The key reactions of organic compounds are considered: synthesis of the salts of organic acids, acylation, substitution, dehalogenation, esterification, hydrometallation and other reactions. Primary attention is devoted to systems and compounds that cannot be obtained by traditional chemistry methods.

Polyoxometalate-based Catalysts for Toxic Compound Decontamination and Solar Energy Conversion

Science.gov (United States)

Guo, Weiwei

Polyoxometalates (POMs) have been attracting interest from researchers in the fields of Inorganic Chemistry, Physical Chemistry, Biomolecular Chemistry, etc. Their unique structures and properties render them versatile and facilitate applications in medicine, magnetism, electrochemistry, photochemistry and catalysis. In particular, toxic compound (chemical warfare agents (CWAs) and toxic industrial compounds (TICs)) decontamination and solar energy conversion by POM-based materials have becoming promising and important research areas that deserve much attention. The focus of this thesis is to explore the structural features of POMs, to develop POM-based materials and to investigate their applications in toxic compound decontamination and solar energy conversion. The first part of this thesis gives a general introduction on the history, structures, properties and applications of POMs. The second part reports the synthesis, structures, and reactivity of different types of POMs in the destruction of TICs and CWAs. Three tetra-n-butylammonium (TBA) salts of polyvanadotungstates, [n-Bu4N]6[ PW9V3], [n-Bu4N] 5H2PW8V4O40 (PW 8V4), [n-Bu4N]4H 5PW6V6O40· 20H2O (PW6V6) are discussed in detail. These vanadium-substituted Keggin type POMs show effective activity for the aerobic oxidation of formaldehyde (a major TIC and human-environment carcingen) to formic acid under ambient conditions. Moreover, two types of POMs have also been developed for the removal of CWAs and/or their simulants. Specifically, a layered manganese(IV)-containing heteropolyvanadate with a 1:14 Stoichiometry, K4Li2[MnV14O40]˙21H2 O has been prepared. Its catalytic activity for oxidative removal of 2-chloroethyl ethyl sulfide (a mustard simulant) is discussed. The second type of POM developed for decontamination of CWAs and their simulants is the new one-dimensional polymeric polyniobate (P-PONb), K12[Ti 2O2][GeNb12O40]˙19H2O (KGeNb). The complex has been applied to the decontamination of a wide range

From energy-rich phosphate compounds to warfare agents: A review on the chemistry of organic phosphate compounds

Directory of Open Access Journals (Sweden)

Luciano Albino Giusti

2008-12-01

Full Text Available The chemistry of the phosphorus-oxygen bond is widely used in biological systems in many processes, such as energy transduction and the storage, transmission and expression of genetic information, which are essential to living beings in relation to a wide variety of functions. Compounds containing this bond have been designed for many purposes, ranging from agricultural defense systems, in order to increase food production, to nerve agents, for complaining use in warfare. In this review, features related to the chemistry of organic phosphate compounds are discussed, with particular emphasis on the role of phosphate compounds in biochemical events and in nerve agents. To this aim, the energy-rich phosphate compounds are focused, particularly the mode of their use as energy currency in cells. Historical and recent studies carried out by research groups have tried to elucidate the mechanism of action of enzymes responsible for energy transduction through the use of biochemical studies, enzyme models, and artificial enzymes. Finally, recent studies on the detoxification of nerve agents based on phosphorous esters are presented, and on the utilization of chromogenic and fluorogenic chemosensors for the detection of these phosphate species.

Developmental toxicity of thyroid-active compounds in a zebrafish embryotoxicity test

NARCIS (Netherlands)

Jomaa, B.; Hermsen, S.A.B.; Kessels, M.Y.; Berg, van den J.H.J.; Peijenburg, A.C.M.; Aarts, J.M.M.J.G.; Piersma, A.H.; Rietjens, I.

2014-01-01

Zebrafish embryos were exposed to concentration ranges of selected thyroid-active model compounds in order to assess the applicability of zebrafish-based developmental scoring systems within an alternative testing strategy to detect the developmental toxicity of thyroid-active compounds. Model

Cyanobacteria as a Source for Novel Anti-Leukemic Compounds.

Science.gov (United States)

Humisto, Anu; Herfindal, Lars; Jokela, Jouni; Karkman, Antti; Bjørnstad, Ronja; Choudhury, Romi R; Sivonen, Kaarina

2016-01-01

Cyanobacteria are an inspiring source of bioactive secondary metabolites. These bioactive agents are a diverse group of compounds which are varying in their bioactive targets, the mechanisms of action, and chemical structures. Cyanobacteria from various environments, especially marine benthic cyanobacteria, are found to be rich sources for the search for novel bioactive compounds. Several compounds with anticancer activities have been discovered from cyanobacteria and some of these have succeeded to enter the clinical trials. Varying anticancer agents are needed to overcome increasing challenges in cancer treatments. Different search methods are used to reveal anticancer compounds from natural products, but cell based methods are the most common. Cyanobacterial bioactive compounds as agents against acute myeloid leukemia are not well studied. Here we examined our new results combined with previous studies of anti-leukemic compounds from cyanobacteria with emphasis to reveal common features in strains producing such activity. We report that cyanobacteria harbor specific anti-leukemic compounds since several studied strains induced apoptosis against AML cells but were inactive against non-malignant cells like hepatocytes. We noted that particularly benthic strains from the Baltic Sea, such as Anabaena sp., were especially potential AML apoptosis inducers. Taken together, this review and re-analysis of data demonstrates the power of maintaining large culture collections for the search for novel bioactivities, and also how anti-AML activity in cyanobacteria can be revealed by relatively simple and low-cost assays.

A Non-lethal water-based removal-reapplication technique for behavioral analysis of cuticular compounds of ants.

Science.gov (United States)

Roux, Olivier; Martin, Jean-Michel; Ghomsi, Nathan Tene; Dejean, Alain

2009-08-01

Interspecific relationships among insects are often mediated by chemical cues, including non-volatile cuticular compounds. Most of these compounds are hydrocarbons that necessitate the use of solvents for their extraction, identification, and manipulation during behavioral assays. The toxicity of these solvents often precludes the removal and reapplication of hydrocarbons from and to live insects. As a consequence, dummies often are used in behavioral assays, but their passivity can bias the behavior of the responding insects. To overcome these limitations, we propose a method where cuticular compounds are extracted from live ants by placing them into glass vials half-filled with tepid water (ca. 34 degrees C) and vigorously shaking the vials to form an emulsion whose supernatant can be analyzed and/or reapplied to other ants. We demonstrate that cuticular compounds can be extracted from workers of the red fire ant, Solenopsis saevissima, and reapplied to the cuticle of workers from a sympatric species, Camponotus blandus (both Hymenoptera: Formicidae), while keeping the ants alive. Gas chromatographic-mass spectrometric analysis and behavioral assays were used to confirm the successful transfer of the behaviorally active compounds.

Antiphase Fermi-surface modulations accompanying displacement excitation in a parent compound of iron-based superconductors

Science.gov (United States)

Okazaki, Kozo; Suzuki, Hakuto; Suzuki, Takeshi; Yamamoto, Takashi; Someya, Takashi; Ogawa, Yu; Okada, Masaru; Fujisawa, Masami; Kanai, Teruto; Ishii, Nobuhisa; Itatani, Jiro; Nakajima, Masamichi; Eisaki, Hiroshi; Fujimori, Atsushi; Shin, Shik

2018-03-01

We investigate the transient electronic structure of BaFe2As2 , a parent compound of iron-based superconductors, by time- and angle-resolved photoemission spectroscopy. In order to probe the entire Brillouin zone, we utilize extreme ultraviolet photons and observe photoemission intensity oscillation with the frequency of the A1 g phonon which is antiphase between the zone-centered hole Fermi surfaces (FSs) and zone-cornered electron FSs. We attribute the antiphase behavior to the warping in one of the zone-centered hole FSs accompanying the displacement of the pnictogen height and find that this displacement is the same direction as that induced by substitution of P for As, where superconductivity is induced by a structural modification without carrier doping in this system.

Projection-type X-ray microscope based on a spherical compound refractive X-ray lens

OpenAIRE

Dudchik, Yu. I.; Gary, C. K.; Park, H.; Pantell, R. H.; Piestrup, M. A.

2007-01-01

New projection- type X-ray microscope with a compound refractive lens as the optical element is presented. The microscope consists of an X-ray source that is 1-2 mm in diameter, compound X-ray lens and X-ray camera that are placed in-line to satisfy the lens formula. The lens forms an image of the X-ray source at camera sensitive plate. An object is placed between the X-ray source and the lens as close as possible to the source, and the camera shows a shadow image of the object. Spatial resol...

Mining collections of compounds with Screening Assistant 2.

Science.gov (United States)

Guilloux, Vincent Le; Arrault, Alban; Colliandre, Lionel; Bourg, Stéphane; Vayer, Philippe; Morin-Allory, Luc

2012-08-31

High-throughput screening assays have become the starting point of many drug discovery programs for large pharmaceutical companies as well as academic organisations. Despite the increasing throughput of screening technologies, the almost infinite chemical space remains out of reach, calling for tools dedicated to the analysis and selection of the compound collections intended to be screened. We present Screening Assistant 2 (SA2), an open-source JAVA software dedicated to the storage and analysis of small to very large chemical libraries. SA2 stores unique molecules in a MySQL database, and encapsulates several chemoinformatics methods, among which: providers management, interactive visualisation, scaffold analysis, diverse subset creation, descriptors calculation, sub-structure / SMART search, similarity search and filtering. We illustrate the use of SA2 by analysing the composition of a database of 15 million compounds collected from 73 providers, in terms of scaffolds, frameworks, and undesired properties as defined by recently proposed HTS SMARTS filters. We also show how the software can be used to create diverse libraries based on existing ones. Screening Assistant 2 is a user-friendly, open-source software that can be used to manage collections of compounds and perform simple to advanced chemoinformatics analyses. Its modular design and growing documentation facilitate the addition of new functionalities, calling for contributions from the community. The software can be downloaded at http://sa2.sourceforge.net/.

The single crystal structure determination of Ln{sub 6}MnSb{sub 15} (Ln=La, Ce), Ln{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} (x∝0.5), and Ln{sub 6}ZnSb{sub 15} (Ln=La-Pr)

Energy Technology Data Exchange (ETDEWEB)

Benavides, Katherine A.; McCandless, Gregory T.; Chan, Julia Y. [Texas Univ., Dallas, Richardson, TX (United States). Dept. of Chemistry and Biochemistry

2017-09-01

Single crystals of Ln{sub 6}MnSb{sub 15} (Ln=La, Ce), Ln{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} (x∝0.5), and Ln{sub 6}ZnSb{sub 15} (Ln=La-Pr) have been successfully grown and the compounds adopt the orthorhombic Ln{sub 6}MnSb{sub 15} structure type (space group Immm), with a∝4.3 Aa, b∝15 Aa, and c∝19 Aa. This structure is comprised of antimony nets and antimony ribbons which exhibit positional disorder at connecting points between antimony substructures, in addition to two partially occupied transition metal sites. The unit cell volumes of the La analogs displayed a systematic decrease upon Zn substitution. However, for the Ce{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} and Pr{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} (x∝0.5), the volumes deviate from linearity as observed in the parent compounds.

USING H.264/AVC-INTRA FOR DCT BASED SEGMENTATION DRIVEN COMPOUND IMAGE COMPRESSION

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S. Ebenezer Juliet

2011-08-01

Full Text Available This paper presents a one pass block classification algorithm for efficient coding of compound images which consists of multimedia elements like text, graphics and natural images. The objective is to minimize the loss of visual quality of text during compression by separating text information which needs high special resolution than the pictures and background. It segments computer screen images into text/graphics and picture/background classes based on DCT energy in each 4x4 block, and then compresses both text/graphics pixels and picture/background blocks by H.264/AVC with variable quantization parameter. Experimental results show that the single H.264/AVC-INTRA coder with variable quantization outperforms single coders such as JPEG, JPEG-2000 for compound images. Also the proposed method improves the PSNR value significantly than standard JPEG, JPEG-2000 and while keeping competitive compression ratios.

Synthesis and anti-lung cancer activity of a novel arsenomolybdate compound

Science.gov (United States)

Zhu, Tian-Tian; Wang, Juan; Chen, Song-Hu

2017-12-01

The new compound based on Wells-Dawson-type arsenomolybdate: [{Cu10(pz)11Cl4}{As2IIIAs2VMo6VMo12VIO62}]·H2O (1) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction analysis, X-ray powder diffraction (XRPD), XPS spectroscopy and thermogravimetric analysis (TG). Compound 1 is consisted of two As caps Wells-dawson-type arsenomolybdate and {Cu10(py)11} complexes by chloride bridge. In addition, the antitumor effects of the title compound 1 were studied on three human lung cancer cells (A549, SK-LU-1 and SW1573). The results showed that compared with the positive reference drug carboplatin, compound 1 displayed efficient antitumor activity.

A process for producing lignin and volatile compounds from hydrolysis liquor.

Science.gov (United States)

Khazraie, Tooran; Zhang, Yiqian; Tarasov, Dmitry; Gao, Weijue; Price, Jacquelyn; DeMartini, Nikolai; Hupa, Leena; Fatehi, Pedram

2017-01-01

Hot water hydrolysis process is commercially applied for treating wood chips prior to pulping or wood pellet production, while it produces hydrolysis liquor as a by-product. Since the hydrolysis liquor is dilute, the production of value-added materials from it would be challenging. In this study, acidification was proposed as a viable method to extract (1) furfural and acetic acid from hot water hydrolysis liquor and (2) lignin compounds from the liquor. The thermal properties of the precipitates made from the acidification of hydrolysis liquor confirmed the volatile characteristics of precipitates. Membrane dialysis was effective in removing inorganic salts associated with lignin compounds. The purified lignin compounds had a glass transition temperature (Tg) of 180-190 °C, and were thermally stable. The results confirmed that lignin compounds present in hot water hydrolysis liquor had different characteristics. The acidification of hydrolysis liquor primarily removed the volatile compounds from hydrolysis liquor. Based on these results, a process for producing purified lignin and precipitates of volatile compounds was proposed.

Termite Resistance of MDF Panels Treated with Various Boron Compounds

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Sedat Ondaral

2009-06-01

Full Text Available In this study, the effects of various boron compounds on the termite resistance of MDF panels were evaluated. Either borax (BX, boric acid (BA, zinc borate (ZB, or sodium perborate tetrahydrate (SPT were added to urea-formaldehyde (UF resin at target contents of 1%, 1.5%, 2% and 2.5% based on dry fiber weight. The panels were then manufactured using 12% urea-formaldehyde resin and 1% NH4Cl. MDF samples from the panels were tested against the subterranean termites, Coptotermes formosanus Shiraki. Laboratory termite resistance tests showed that all samples containing boron compounds had greater resistance against termite attack compared to untreated MDF samples. At the second and third weeks of exposure, nearly 100% termite mortalities were recorded in all boron compound treated samples. The highest termite mortalities were determined in the samples with either BA or BX. Also, it was found that SPT showed notable performance on the termite mortality. As chemical loadings increased, termite mortalities increased, and at the same time the weight losses of the samples decreased.

Marine Fungi: A Source of Potential Anticancer Compounds

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Sunil K. Deshmukh

2018-01-01

Full Text Available Metabolites from marine fungi have hogged the limelight in drug discovery because of their promise as therapeutic agents. A number of metabolites related to marine fungi have been discovered from various sources which are known to possess a range of activities as antibacterial, antiviral and anticancer agents. Although, over a thousand marine fungi based metabolites have already been reported, none of them have reached the market yet which could partly be related to non-comprehensive screening approaches and lack of sustained lead optimization. The origin of these marine fungal metabolites is varied as their habitats have been reported from various sources such as sponge, algae, mangrove derived fungi, and fungi from bottom sediments. The importance of these natural compounds is based on their cytotoxicity and related activities that emanate from the diversity in their chemical structures and functional groups present on them. This review covers the majority of anticancer compounds isolated from marine fungi during 2012–2016 against specific cancer cell lines.

Bond-based linear indices in QSAR: computational discovery of novel anti-trichomonal compounds

Science.gov (United States)

Marrero-Ponce, Yovani; Meneses-Marcel, Alfredo; Rivera-Borroto, Oscar M.; García-Domenech, Ramón; De Julián-Ortiz, Jesus Vicente; Montero, Alina; Escario, José Antonio; Barrio, Alicia Gómez; Pereira, David Montero; Nogal, Juan José; Grau, Ricardo; Torrens, Francisco; Vogel, Christian; Arán, Vicente J.

2008-08-01

Trichomonas vaginalis ( Tv) is the causative agent of the most common, non-viral, sexually transmitted disease in women and men worldwide. Since 1959, metronidazole (MTZ) has been the drug of choice in the systemic treatment of trichomoniasis. However, resistance to MTZ in some patients and the great cost associated with the development of new trichomonacidals make necessary the development of computational methods that shorten the drug discovery pipeline. Toward this end, bond-based linear indices, new TOMOCOMD-CARDD molecular descriptors, and linear discriminant analysis were used to discover novel trichomonacidal chemicals. The obtained models, using non-stochastic and stochastic indices, are able to classify correctly 89.01% (87.50%) and 82.42% (84.38%) of the chemicals in the training (test) sets, respectively. These results validate the models for their use in the ligand-based virtual screening. In addition, they show large Matthews' correlation coefficients ( C) of 0.78 (0.71) and 0.65 (0.65) for the training (test) sets, correspondingly. The result of predictions on the 10% full-out cross-validation test also evidences the robustness of the obtained models. Later, both models are applied to the virtual screening of 12 compounds already proved against Tv. As a result, they correctly classify 10 out of 12 (83.33%) and 9 out of 12 (75.00%) of the chemicals, respectively; which is the most important criterion for validating the models. Besides, these classification functions are applied to a library of seven chemicals in order to find novel antitrichomonal agents. These compounds are synthesized and tested for in vitro activity against Tv. As a result, experimental observations approached to theoretical predictions, since it was obtained a correct classification of 85.71% (6 out of 7) of the chemicals. Moreover, out of the seven compounds that are screened, synthesized and biologically assayed, six compounds (VA7-34, VA7-35, VA7-37, VA7-38, VA7-68, VA7-70) show

MnFe(PGe) compounds: Preparation, structural evolution, and magnetocaloric effects

International Nuclear Information System (INIS)

Yue Ming; Zhang Hong-Guo; Zhang Jiu-Xing; Liu Dan-Min

2015-01-01

The interdependences of preparation conditions, magnetic and crystal structures, and magnetocaloric effects (MCE) of the MnFePGe-based compounds are reviewed. Based upon those findings, a new method for the evaluation of the MCE in these compounds, based on differential scanning calorimetry (DSC), is proposed. The MnFePGe-based compounds are a group of magnetic refrigerants with giant magnetocaloric effect (GMCE), and as such, have drawn tremendous attention, especially due to their many advantages for practical applications. Structural evolution and phase transformation in the compounds as functions of temperature, pressure, and magnetic field are reported. Influences of preparation conditions upon the homogeneity of the compounds’ chemical composition and microstructure, both of which play a key role in the MCE and thermal hysteresis of the compounds, are introduced. Lastly, the origin of the “virgin effect” in the MnFePGe-based compounds is discussed. (paper)

New procedure for the examination of the degradation of volatile organonitrogen compounds during the treatment of industrial effluents.

Science.gov (United States)

Boczkaj, Grzegorz; Makoś, Patrycja; Fernandes, Andre; Przyjazny, Andrzej

2017-03-01

We present a new procedure for the determination of 32 volatile organonitrogen compounds in samples of industrial effluents with a complex matrix. The procedure, based on dispersive liquid-liquid microextraction followed by gas chromatography with nitrogen-phosphorus and mass spectrometric detection, was optimized and validated. Optimization of the extraction included the type of extraction and disperser solvent, disperser solvent volume, pH, salting out effect, extraction, and centrifugation time. The procedure based on nitrogen-phosphorus detection was found to be superior, having lower limits of detection (0.0067-2.29 μg/mL) and quantitation as well as a wider linear range. The developed procedure was applied to the determination of content of volatile organonitrogen compounds in samples of raw effluents from the production of bitumens in which 13 compounds were identified at concentrations ranging from 0.15 to 10.86 μg/mL and in samples of effluents treated by various chemical methods. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Peduncular Cystic Compound Odontoma on the Posterior Wall of the Maxillary Sinus

Energy Technology Data Exchange (ETDEWEB)

Kang, Byung Chul [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Chonam National University, Kwangju (Korea, Republic of)

1998-08-15

A cystic compound odontoma in the maxillary sinus occurred in a 13-years-old boy, who had missing right upper third molar without having the history of extraction of the wisdom tooth. He complained nasal stuffiness, headache, and pain on the affected face, resembling any sign and symptoms of the maxillary sinus problems. The cysteic compound, sized 2 x 1.5 cm in diameter was pedunculated and attached on the posterior wall of the right maxillary sinus and above the antral floor. The location of the compound odontoma in the maxillary sinus was confirmed after panoramic, waters, spiral tomographic, CT examinations and surgical exploration. Irs location was on the medical, posterior, superior to the normal position of the maxillary third molar or the maxillary dental arch. The cystic odontoma in the maxillary sinus made the patient have the sings and symptoms of maxillary sinusitis. The cystic compound odontoma might be originated from the dental lamina of the missing upper right third molar. The 'V principle' of the upper jaw growth and the pneumatization process of the maxillary sinus could explain why the compound odontoma had peduncular shape and the location of odontoma was on the medial, superior to the normal position of the maxillary dental arch.

The insoluble carbonaceous material of CM chondrites: A possible source of discrete organic compounds under hydrothermal conditions

Science.gov (United States)

Yabuta, Hikaru; Williams, Lynda B.; Cody, George D.; Alexander, Conel M. O. D.; Pizzarello, Sandra

2007-08-01

We report on the molecular analyses of the water- and solvent-soluble organic compounds released from the insoluble organic material (IOM) of the Murray meteorite upon treatment with weight-equivalent amounts of water and under conditions of elevated temperature and pressure. A varied suite of compounds was identified by gas chromatography-mass spectrometry (GC-MS). C3-C17 alkyl dicarboxylic acids and N- and O-containing hydroaromatic and aromatic compounds were found in the water extracts. The solvent extracts contained N-, O-, and S-containing aromatic compounds, a large number of their isomers and homologs, and a series of polycyclic aromatic hydrocarbons (PAHs) of up to five rings, together with noncondensed aromatic species such as substituted benzenes, biphenyl, and terphenyls as well as their substituted homologs, and hydrated PAHs. Isotopic analyses showed that residue IOMs after hydrothermal treatment had lower deuterium and 15N content than the untreated material (ΔD = -833‰ and Δ15N = -24.1) but did not differ from it in 13C composition. The effect of the hydrothermolytic release was recorded in significant differences between the NMR spectra of untreated and residue IOM. A possible relation to common precursors for the dicarboxylic acids found in the IOM and bulk extracts is discussed.

The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors

Directory of Open Access Journals (Sweden)

Faith M. Akwi

2016-09-01

Full Text Available In this paper, a micro-fluidic optimized process for the continuous flow synthesis of azo compounds is presented. The continuous flow synthesis of Sudan II azo dye was used as a model reaction for the study. At found optimal azo coupling reaction temperature and pH an investigation of the optimum flow rates of the reactants for the diazotization and azo coupling reactions in Little Things Factory-MS microreactors was performed. A conversion of 98% was achieved in approximately 2.4 minutes and a small library of azo compounds was thus generated under these reaction conditions from couplers with aminated or hydroxylated aromatic systems. The scaled up synthesis of these compounds in PTFE tubing (i.d. 1.5 mm was also investigated, where good reaction conversions ranging between 66–91% were attained.

From crystal to compound: structure-based antimalarial drug discovery.

Science.gov (United States)

Drinkwater, Nyssa; McGowan, Sheena

2014-08-01

Despite a century of control and eradication campaigns, malaria remains one of the world's most devastating diseases. Our once-powerful therapeutic weapons are losing the war against the Plasmodium parasite, whose ability to rapidly develop and spread drug resistance hamper past and present malaria-control efforts. Finding new and effective treatments for malaria is now a top global health priority, fuelling an increase in funding and promoting open-source collaborations between researchers and pharmaceutical consortia around the world. The result of this is rapid advances in drug discovery approaches and technologies, with three major methods for antimalarial drug development emerging: (i) chemistry-based, (ii) target-based, and (iii) cell-based. Common to all three of these approaches is the unique ability of structural biology to inform and accelerate drug development. Where possible, SBDD (structure-based drug discovery) is a foundation for antimalarial drug development programmes, and has been invaluable to the development of a number of current pre-clinical and clinical candidates. However, as we expand our understanding of the malarial life cycle and mechanisms of resistance development, SBDD as a field must continue to evolve in order to develop compounds that adhere to the ideal characteristics for novel antimalarial therapeutics and to avoid high attrition rates pre- and post-clinic. In the present review, we aim to examine the contribution that SBDD has made to current antimalarial drug development efforts, covering hit discovery to lead optimization and prevention of parasite resistance. Finally, the potential for structural biology, particularly high-throughput structural genomics programmes, to identify future targets for drug discovery are discussed.

Stochastic Interest Model Based on Compound Poisson Process and Applications in Actuarial Science

OpenAIRE

Li, Shilong; Yin, Chuancun; Zhao, Xia; Dai, Hongshuai

2017-01-01

Considering stochastic behavior of interest rates in financial market, we construct a new class of interest models based on compound Poisson process. Different from the references, this paper describes the randomness of interest rates by modeling the force of interest with Poisson random jumps directly. To solve the problem in calculation of accumulated interest force function, one important integral technique is employed. And a conception called the critical value is introduced to investigat...

Rapid Deposition of Oxidized Biogenic Compounds to a Temperate Forest

Science.gov (United States)

Nguyen, Tran B.; Crounse, John D.; Teng, Alex P.; St. Clair, Jason M.; Paulot, Fabien; Wolfe, Glenn M.; Wennberg, Paul O.

2015-01-01

We report fluxes and dry deposition velocities for 16 atmospheric compounds above a southeastern United States forest, including: hydrogen peroxide (H2O2), nitric acid (HNO3), hydrogen cyanide (HCN), hydroxymethyl hydroperoxide, peroxyacetic acid, organic hydroxy nitrates, and other multifunctional species derived from the oxidation of isoprene and monoterpenes. The data suggest that dry deposition is the dominant daytime sink for small, saturated oxygenates. Greater than 6 wt %C emitted as isoprene by the forest was returned by dry deposition of its oxidized products. Peroxides account for a large fraction of the oxidant flux, possibly eclipsing ozone in more pristine regions. The measured organic nitrates comprise a sizable portion (15%) of the oxidized nitrogen input into the canopy, with HNO3 making up the balance. We observe that water-soluble compounds (e.g., strong acids and hydroperoxides) deposit with low surface resistance whereas compounds with moderate solubility (e.g., organic nitrates and hydroxycarbonyls) or poor solubility (e.g., HCN) exhibited reduced uptake at the surface of plants. To first order, the relative deposition velocities of water-soluble compounds are constrained by their molecular diffusivity. From resistance modeling, we infer a substantial emission flux of formic acid at the canopy level (approx. 1 nmol m(exp.-2)·s(exp.-1)). GEOS-Chem, awidely used atmospheric chemical transport model, currently underestimates dry deposition for most molecules studied in this work. Reconciling GEOS-Chem deposition velocities with observations resulted in up to a 45% decrease in the simulated surface concentration of trace gases.

Studying the fate of non-volatile organic compounds in a commercial plasma air purifier

Energy Technology Data Exchange (ETDEWEB)

Schmid, Stefan [ETH Zürich, Department of Chemistry and Applied Biosciences, CH-8093 Zürich (Switzerland); Seiler, Cornelia; Gerecke, Andreas C. [Swiss Federal Laboratories for Material Science and Technology (EMPA), CH-8600 Dübendorf (Switzerland); Hächler, Herbert [University of Zürich, Institute for Food Safety and Hygiene, National Centre for Enteropathogenic Bacteria and Listeria (NENT), CH-8057 Zürich (Switzerland); Hilbi, Hubert [Ludwig-Maximilians-Universität München Max von Pettenkofer-Institut, D-80336 München (Germany); Frey, Joachim [University of Bern, Institute for Veterinary Bacteriology, CH-3001 Bern (Switzerland); Weidmann, Simon; Meier, Lukas; Berchtold, Christian [ETH Zürich, Department of Chemistry and Applied Biosciences, CH-8093 Zürich (Switzerland); Zenobi, Renato, E-mail: zenobi@org.chem.ethz.ch [ETH Zürich, Department of Chemistry and Applied Biosciences, CH-8093 Zürich (Switzerland)

2013-07-15

Highlights: • Degradation of environmental toxins, a protein, and bioparticles were studied. • A commercial air purifier based on a cold plasma was used. • Passage through the device reduced the concentration of the compounds/particles. • Deposition inside the plasma air purifier was the main removal process. -- Abstract: Degradation of non-volatile organic compounds–environmental toxins (methyltriclosane and phenanthrene), bovine serum albumin, as well as bioparticles (Legionella pneumophila, Bacillus subtilis, and Bacillus anthracis)–in a commercially available plasma air purifier based on a cold plasma was studied in detail, focusing on its efficiency and on the resulting degradation products. This system is capable of handling air flow velocities of up to 3.0 m s{sup −1} (3200 L min{sup −1}), much higher than other plasma-based reactors described in the literature, which generally are limited to air flow rates below 10 L min{sup −1}. Mass balance studies consistently indicated a reduction in concentration of the compounds/particles after passage through the plasma air purifier, 31% for phenanthrene, 17% for methyltriclosane, and 80% for bovine serum albumin. L. pneumophila did not survive passage through the plasma air purifier, and cell counts of aerosolized spores of B. subtilis and B. anthracis were reduced by 26- and 15-fold, depending on whether it was run at 10 Hz or 50 Hz, respectively. However rather than chemical degradation, deposition on the inner surfaces of the plasma air purifier occured. Our interpretation is that putative “degradation” efficiencies were largely due to electrostatic precipitation rather than to decomposition into smaller molecules.

Characterisation of selected volatile organic compounds in ...

African Journals Online (AJOL)

kshale

2013-05-15

May 15, 2013 ... have entered the commercial market, both in rural areas ... nation of volatile compounds include: gas chromate- graphy (GC) ... prior to the actual analysis, various extraction methods ..... traditional and industrial 'orujo' spirits.

Superconductivity in Ti3P-type compounds

International Nuclear Information System (INIS)

Wills, J.O.; Hein, R.A.; Waterstrat, R.M.

1978-01-01

A study of 12 intermetallic A 3 B compounds which crsytallize in the tetragonal Ti 3 P-type structure has revealed five new superconductors with transition temperatures below 1 K: Zr 3 Si, Zr 3 Ge, Zr 3 P, V 3 P, and Nb 3 Ge (extrapolated from the alloy series Nb-Ge-As). In addition, two compounds, Zr 3 Sb and Ta 3 Ge, having the Ni 3 P structure type are found to be superconducting below 1 K. Within the Ti 3 P-type compounds, those with the lighter ''B'' elements in a given column of the Periodic Table have the higher transition temperatures. Critical-magnetic-field and electrical-resistivity data are reported for the superconducting Ti 2 P-type compound Nb 3 P, which permit one to estimate the Ginzburg-Landau kappa parameter and the electronic-specific-heat coefficient γ. The kappa value of 8.4 indicates that this material is type II, and the γ value of 1.3 mJ/mole K 2 for Nb 3 P is probably related to its low transition temperature relative to many A15 compounds

Synthesis and luminescent properties of star-burst D-π-A compounds based on 1,3,5-triazine core and carbazole end-capped phenylene ethynylene arms

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zheng [Department of Applied Chemistry, Nanjing Tech University, Nanjing 210009 (China); Liu, Rui, E-mail: rui.liu@njtech.edu.cn [Department of Applied Chemistry, Nanjing Tech University, Nanjing 210009 (China); Zhu, Xiaolin [Department of Applied Chemistry, Nanjing Tech University, Nanjing 210009 (China); Li, Yuhao [Department of Chemistry, Fudan University, 220 Handan Road, Shanghai 200433 (China); Chang, Jin [Queensland University of Technology, 2 George St., Brisbane 4000 (Australia); Zhu, Hongjun, E-mail: zhuhjnjut@hotmail.com [Department of Applied Chemistry, Nanjing Tech University, Nanjing 210009 (China); Ma, Liangwei; Lv, Wangjie; Guo, Jun [Department of Applied Chemistry, Nanjing Tech University, Nanjing 210009 (China)

2014-12-15

Two new star-burst compounds based on 1,3,5-triazine core and carbazole end-capped phenylene ethynylene arms (1a and 1b) were synthesized and characterized. Their photophysical properties were investigated systematically via spectroscopic and theoretical methods. Both compounds exhibit strong {sup 1}π–π{sup ⁎} transitions in the UV region and intense {sup 1}π–π{sup ⁎}/intramolecular charge transfer ({sup 1}ICT) absorption bands in the UV–vis region. Introducing the carbazole end-capped phenylene ethynylene arm on the 1,3,5-triazine core causes a slight bathochromic shift and enhanced molar extinction coefficient of the {sup 1}π–π{sup ⁎}/{sup 1}ICT transition band. Both compounds are emissive in solution at room temperature and 77 K, which exhibit pronounced positive solvatochromic effect. The emitting state could be ascribed to {sup 1}ICT state in more polar solvent, and {sup 1}π–π{sup ⁎} state in low-polarity solvent. The high emission quantum yields (Φ{sub em}=0.90∼1.0) of 1a and 1b (in hexane and toluene) make them potential candidates as efficient light-emitting materials. The spectroscopic studies and theoretical calculations indicate that the photophysical properties of these compounds can be tuned by the carbazole end-capped phenylene ethynylene arm, which would also be useful for rational design of photofunctional materials. - Highlights: • Star-burst compounds based on 1,3,5-triazine core and carbazole end-capped phenylene ethynylene arms. • Photophysical properties of target compounds were investigated systematically via spectroscopic and theoretical methods. • The relatively high fluorescence quantum yields make them potential candidates as light-emitting materials.

Binding thermodynamics discriminates fragments from druglike compounds: a thermodynamic description of fragment-based drug discovery.

Science.gov (United States)

Williams, Glyn; Ferenczy, György G; Ulander, Johan; Keserű, György M

2017-04-01

Small is beautiful - reducing the size and complexity of chemical starting points for drug design allows better sampling of chemical space, reveals the most energetically important interactions within protein-binding sites and can lead to improvements in the physicochemical properties of the final drug. The impact of fragment-based drug discovery (FBDD) on recent drug discovery projects and our improved knowledge of the structural and thermodynamic details of ligand binding has prompted us to explore the relationships between ligand-binding thermodynamics and FBDD. Information on binding thermodynamics can give insights into the contributions to protein-ligand interactions and could therefore be used to prioritise compounds with a high degree of specificity in forming key interactions. Copyright © 2016 Elsevier Ltd. All rights reserved.

The behavior of intermetallic compounds at large plastic strains

International Nuclear Information System (INIS)

Gray, G.T.; Embury, J.D.

1993-01-01

This paper contains a summary of a broad study of intermetallics which includes the following materials, Ni 3 Al, Ti-48Al-1V, Ti-24Al-11Nb, Ti-48Al-2Cr-2Nb, and Ti-24.5 Al-10.5Nb-1.5Mo. Much effort has been devoted to the study of ordered materials at modes plastic strains and the problem of premature failure. However by utilizing stress states other than simple tension it is possible to study the deformation of intermetallic compounds up to large plastic strains and to consider the behavior of these materials in the regime where stresses approach the theoretical stress. The current work outlines studies of the work hardening rate of a number of titanium and nickel-based intermetallic compounds deformed in compression. Attention is given to the structural basis of the sustained work hardening. The large strain plasticity of these materials is summarized in a series of diagrams. Fracture in these materials in compression occurs via catastrophic shear at stresses of the order of E/80 (where E is the elastic modulus)

Structure and magnetic properties of Ba5Ce1.25Mn3.75O15, a new 10H-polytype in the Ba–Ce–Mn–O system

International Nuclear Information System (INIS)

Macías, Mario A.; Mentré, Olivier; Colis, Silviu; Cuello, Gabriel J.; Gauthier, Gilles H.

2013-01-01

Based on the peculiar magnetic properties that are observed in pseudo one-dimensional manganites, we decided to synthesize the new Ba 5 Ce 1.25 Mn 3.75 O 15 compound. The preparation was performed by solid state reaction in air at about 1350 °C, for which we found that the compound crystallizes in a hexagonal symmetry with space group P6 3 /mmc (No-194) and cell parameters a=b=5.7861(2) Å and c=23.902(1) Å. The structural description was correlated with neutron diffraction and bond valence calculations, confirming the presence of Ce 4+ and Mn 4+ segregated in the different crystallographic positions. Ba 5 Ce 1.25 Mn 3.75 O 15 displays evidence for strong AFM couplings already set at room temperature. The main arrangement of Mn 4+ in magnetically isolated tetramers of face-sharing octahedra is responsible for a metamagnetic-like transition around 50 K. - Graphical abstract: The new Ba 5 Ce 1.25 Mn 3.75 O 15 polytype shows strong AFM couplings in magnetically isolated [Ce 0.25 Mn 3.75 O 15 ] tetramers of face-sharing octahedral, resulting in a metamagnetic-like transition around 50 K. Highlights: ► Ba 5 Ce 1.25 Mn 3.75 O 15 , a new 10H polytype, has been prepared in the Ba–Ce–Mn–O system. ► The compound crystallizes in the P6 3 /mmc space group with (cchhh) 2 stacking sequence. ► [Ce 0.25 Mn 3.75 O 15 ] tetramers are separated by [CeO 6 ] octahedra in the structure. ► Instead of robust AFM ordering, a metamagnetic-like transition is found around 50 K.

Lithium insertion in the two crystallographic forms of the binary-phase Mo15Se19

International Nuclear Information System (INIS)

Tarascon, J.M.; Murphy, D.W.

1986-01-01

Compounds which can undergo topotactic insertion of lithium are of potential technological importance in secondary lithium batteries. In this paper we present the chemical and electrochemical insertion of lithium into the binary-phase Mo 15 Se 19 , which can exist in two crystallographic forms, denoted AA and BB, when prepared from In 3 Mo 15 Se 19 and In 2 Mo 15 Se 19 , respectively. We show that both forms can reversibly accommodate up to eight lithium atoms, yielding two new series of compounds of formula Li/sub x/Mo 15 Se 19 . This behavior is consistent with the electronic structure of the host material predicted from band-structure calculations. The room-temperature phase diagram of both Li/sub x/Mo 15 Se 19 systems as a function of x has been established using electrochemical test cells (based on Mo 15 Se 19 as the cathode), and in situ x-ray measurements as the cells discharge. Both Li/sub x/Mo 15 Se 19 systems contain three single-phase domains as a function of x: two hexagonal phases and an orthorhombic phase. The nature of the transitions between these single phases and the variation of the lattice parameters within a single-phase domain are reported. While the mechanism of intercalation of lithium is similar for both Mo 15 Se 19 forms, there is a drastic difference in Li intercalation behavior for the parent indium phases In''Mo 15 Se 19 and In 3 Mo 15 Se 19 . We found that In 2 Mo 15 Se 19 can reversibly incorporate 6.4 lithium atoms while In 3 Mo 15 Se 19 does not react. This behavior is explained on the basis of structural considerations

EXTRACTION OF PHENOLIC COMPOUNDS FROM PETAI LEAVES (PARKIA SPECIOSA HASSK. USING MICROWAVE AND ULTRASOUND ASSISTED METHODS

Directory of Open Access Journals (Sweden)

Buanasari Buanasari

2017-06-01

Full Text Available The antioxidant has an activity to neutralize free radical compound that the body needs to avoid damage cells and tissues. Phenolic is one of the compounds that have an antioxidant activity. The influences of ultrasonic-assisted extraction (UAE and microwave-assisted extraction (MAE conditions on phenolic compounds of Parkia speciosa Hassk. leaves were investigated. The effects of temperature (40°C, 50°C, 60°C and 70°C, time (10, 30 and 50 minutes and material-solvent ratio (1:10, 1:13, 1:15 were evaluated based on the yield, total phenolic content (TPC and antioxidant activity. The result showed that the highest yield (15.82% was obtained at 1:15 (w/w of material-solvent ratio, 50°C of temperature and 50 minutes of extraction time for MAE. The highest yield of UAE is 15.53% that sample was obtained at 1:13 (w/w of material-solvent ratio, 60°C of optimal temperature and 30 minutes extraction time. The highest IC50 of UAE method extract was 52.55 ppm, while the extract obtained using MAE method was 50.44 ppm. UAE is more stable at higher temperatures. Time and solvent which was used more efficient than MAE. Extract of petai leaves (Parkia speciosa Hassk. were very potential to be used as a source of natural antioxidants because they have IC50 values from 41.39 to 66.00 ppm. Its antioxidants capacity is ranged from strong to very strong capacity.

Electron and phonon properties of 25 A-15 superconductors obtained from heat capacity measurements

International Nuclear Information System (INIS)

Junod, A.

1982-01-01

We review 25 specific heat measurements performed in Geneva on binary and pseudo-binary A-15 compounds. The rather extended temperature range allows us to make reliable estimates of several moments of the phonon spectrum which are required in the theory of superconductivity. The Tsub(c) expression of Allen and Dynes can then be used consistently to estimate the microscopic parameters lambda, eta, Nsub(bs) (Esub(F)), etc. The broad range of values reviewed permits to establish significant correlations between the parameters in stoichiometric and ordered compounds. (orig.)

Synthesis and biological activity of sulfur compounds showing structural analogy with combretastatin A-4

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Santos, Edson dos A. dos; Prado, Paulo C.; Carvalho, Wanderley R. de; Lima, Ricardo V. de; Beatriz, Adilson; Lima, Denis P. de, E-mail: denis.lima@ufms.br [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Departamento de Quimica; Hamel, Ernest [Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute at Frederick, National Institutes of Health, Frederick, MD (United States); Dyba, Marzena A. [Basic Science Program , SAIC-Frederick, Inc., Structural Biophysics Laboratory National Cancer Institute, Frederick, MD (United States); Albuquerque, Sergio [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas

2013-09-01

We extended our previous exploration of sulfur bridges as bioisosteric replacements for atoms forming the bridge between the aromatic rings of combretastatin A-4. Employing coupling reactions between 5-iodo-1,2,3-trimethoxybenzene and substituted thiols, followed by oxidation to sulfones with m-CPBA, different locations for attaching the sulfur atom to ring A through the synthesis of nine compounds were examined. Antitubulin activity was performed with electrophoretically homogenous bovine brain tubulin, and activity occurred with the 1,2,3-trimethoxy-4-[(4-methoxyphenyl)thio]benzene (12), while the other compounds were inactive. The compounds were also tested for leishmanicidal activity using promastigote forms of Leishmania braziliensis (MHOM/BR175/M2904),and the greatest activity was observed with 1,2,3-trimethoxy-4-(phenylthio)benzene (10) and 1,2,3-trimethoxy-4-[(4-methoxyphenyl) sulfinyl]benzene (15). (author)

Accelerating Multiple Compound Comparison Using LINGO-Based Load-Balancing Strategies on Multi-GPUs

OpenAIRE

Lin, Chun-Yuan; Wang, Chung-Hung; Hung, Che-Lun; Lin, Yu-Shiang

2015-01-01

Compound comparison is an important task for the computational chemistry. By the comparison results, potential inhibitors can be found and then used for the pharmacy experiments. The time complexity of a pairwise compound comparison is O(n 2), where n is the maximal length of compounds. In general, the length of compounds is tens to hundreds, and the computation time is small. However, more and more compounds have been synthesized and extracted now, even more than tens of millions. Therefore,...

Semantic relations and compound transparency: A regression study in CARIN theory

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Pham Hien

2013-01-01

Full Text Available According to the CARIN theory of Gagné and Shoben (1997, conceptual relations play an important role in compound interpretation. This study develops three measures gauging the role of conceptual relations, and pits these measures against measures based on latent semantic analysis (Landauer & Dumais, 1997. The CARIN measures successfully predict response latencies in a familiarity categorization task, in a semantic transparency task, and in visual lexical decision. Of the measures based on latent semantic analysis, only a measure orthogonal to the conceptual relations, which instead gauges the extent to which the concepts for the compound’s head and the compound itself are discriminated, also reached significance. Results further indicate that in tasks requiring careful assessment of the meaning of the compound, general knowledge of conceptual relations plays a central role, whereas in the lexical decision task, attention shifts to co-activated meanings and the specifics of the conceptual relations realized in the compound’s modifier family.