WorldWideScience

Sample records for compounds esr-endor studies

  1. Strong resistance of Arabidopsis thaliana and Raphanus sativus seeds for ionizing radiation as studied by ESR, ENDOR, ESE spectroscopy and germination measurement: Effect of long-lived and super-long-lived radicals

    Science.gov (United States)

    Kumagai, Jun; Katoh, Hiromi; Kumada, Takayuki; Tanaka, Atsushi; Tano, Shigemitsu; Miyazaki, Tetsuo

    2000-01-01

    Resistance of seeds for ionizing radiation effects on Arabidopsis thaliana and Raphanus sativus seeds were investigated by ESR, ENDOR, ESE spectroscopy and germination measurement. Two types of free radicals, such as long-lived (LL) and super-long-lived (SL) radicals, were produced by the γ-irradiation in the seeds. More than 90% of the 1 kGy-irradiated-seeds can germinate probably by decreasing the LL radicals by absorbing water. 10 kGy-irradiated-seeds cannot germinate at all probably due to the existence of significant amounts of the SL radicals even after absorbing water.

  2. Strong resistance of Arabidopsis thaliana and Raphanus sativus seeds for ionizing radiation as studied by ESR, ENDOR, ESE spectroscopy and germination measurement: Effect of long-lived and super-long-lived radicals

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Jun E-mail: kumagai@apchem.nagoya-u.ac.jp; Katoh, Hiromi; Kumada, Takayuki; Tanaka, Atsushi; Tano, Shigemitsu; Miyazaki, Tetsuo

    2000-01-01

    Resistance of seeds for ionizing radiation effects on Arabidopsis thaliana and Raphanus sativus seeds were investigated by ESR, ENDOR, ESE spectroscopy and germination measurement. Two types of free radicals, such as long-lived (LL) and super-long-lived (SL) radicals, were produced by the {gamma}-irradiation in the seeds. More than 90% of the 1 kGy-irradiated-seeds can germinate probably by decreasing the LL radicals by absorbing water. 10 kGy-irradiated-seeds cannot germinate at all probably due to the existence of significant amounts of the SL radicals even after absorbing water. (author)

  3. Studying the Propensity of Compounds to Supersaturate

    DEFF Research Database (Denmark)

    Palmelund, Henrik; Madsen, Cecilie Maria; Plum, Jakob;

    2016-01-01

    Supersaturating drug delivery systems can enhance the oral bioavailability of poorly soluble drug compounds. Supersaturation of such compounds has been studied in many different ways; however, a more standardized method is required. The rationale of choosing suitable concentrations of supersatura......Supersaturating drug delivery systems can enhance the oral bioavailability of poorly soluble drug compounds. Supersaturation of such compounds has been studied in many different ways; however, a more standardized method is required. The rationale of choosing suitable concentrations...... of supersaturation to study has previously been very inconsistent. This makes comparisons between studies and compounds difficult, as the propensity of compounds to supersaturate varies greatly. This study presents a standardized method to study the supersaturation of drug compounds. The method allows, both......, for a ranking of compounds according to their supersaturation propensity and the effectiveness of precipitation inhibitors. The time-concentration profile of supersaturation and precipitation was studied in situ for 4 different concentrations for 6 model compounds (albendazole, aprepitant, danazol, felodipine...

  4. Expatriate Compound Living: An Ethnographic Field Study

    DEFF Research Database (Denmark)

    Lauring, Jakob; Selmer, Jan

    2009-01-01

    ethnographic field-work methodology, including interviews and participant observation during a period of three months, this exploratory study investigated 16 Danish business expatriates of a large Danish corporation and their families living in the same compound in Saudi Arabia. They shared their spare time...... and the expatriates had the same working hours in the same subsidiary. Results show that a Danish national group was established and maintained. This in-group dominated life in the compound and at work it may have contributed to the perceptual bias and discriminatory behaviour demonstrated by the Danish expatriates......In certain countries, closed expatriate compounds have developed.  They serve to provide resident expatriates and accompanying family members with a comfortable and safe environment. Unfortunately, not much is known about compound life since associated empirical research is scarce. Through...

  5. Study on Compound Effect of Bonded Magnets

    Institute of Scientific and Technical Information of China (English)

    Chang Ying; Ma Nuo; Yu xiaojun; Li Wei; Liu Changsheng; Lian Fazeng

    2004-01-01

    The compound effect of Nd2Fe14B/Fe3B-Ferrite bonded magnets was studied.The result shows that the value ofβjHC obviously decreases with the ferrite content increasing.In addition, a functional relation between magnetic properties and ferrite content was clearly revealed by the physical relation in the magnetic powders.

  6. Study on resistance coefficient in compound channels

    Institute of Scientific and Technical Information of China (English)

    Kejun Yang; Shuyou Cao; Xingnian Liu; Ron Marshall

    2005-01-01

    This paper presents a further study of the Manning and Darcy-Weisbach resistance coefficients, as they play a significant role in assessing the cross-sectional mean velocity, conveyance capacity and determining the lateral distribution of depth mean velocity and local boundary shear stress in compound channels. The relationships between the local, zonal and overall resistance coefficients, and a wide range of geometries and different roughness between the main channel and the flood plain are established by analyzing a vast amount of experimental data from a British Science and Engineering Research Council Flood Channel Facility (SERC-FCF). And the experimental results also show that the overall Darcy-Weisbach resistance coefficient for a compound channel is the function of Reynolds number, but the function relationship is different from that for a single channel. By comparing and analyzing the conventional methods with the experimental data to predict composite roughness in compound channels, it is found that these methods are not suitable for compound channels. Moreover, the reason why the conventional methods cannot assess correctly the conveyance capacity of com pound channels is also analyzed in this paper.

  7. Quantum chemical studies of estrogenic compounds

    Science.gov (United States)

    Quantum chemical methods are potent tools to provide information on the chemical structure and electronic properties of organic molecules. Modern computational chemistry methods have provided a great deal of insight into the binding of estrogenic compounds to estrogenic receptors (ER), an important ...

  8. Expatriate Compound Living: An Ethnographic Field Study

    DEFF Research Database (Denmark)

    Lauring, Jakob; Selmer, Jan

    2009-01-01

    and the expatriates had the same working hours in the same subsidiary. Results show that a Danish national group was established and maintained. This in-group dominated life in the compound and at work it may have contributed to the perceptual bias and discriminatory behaviour demonstrated by the Danish expatriates...... in their management of the foreign national employees. Implications of these findings are discussed in detail....

  9. Study on austenitic nitrocarburizing without compound layer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, X. [Univ. of Petroleum, Dongying, Shandong (China); Kong, C.; Qiao, Y. [Shandong Polytechnic Univ., Jinan, Shandong (China)

    1995-12-31

    This paper presents an advanced austenitic nitrocarburizing process. Medium-carbon steel was used in austenitic nitrocarburizing with methanol/ammonia atmospheres. A particular hardened case without compound layer was obtained at 680 C processing temperature and a moderate nitrogen potential level and for steel 45 nitrocarburized, there is a fine-grain region beneath the austenite case. The forming and developing mechanism of the fine-grain region was analyzed and the microhardness profiles of the layer before and after ageing were determined. Having the advantages of shorter processing time and a superior hardened case, this treatment is expected to supersede the conventional ferritic nitrocarburizing process in many wear resistance applications.

  10. Syntheses and studies of organosilicon compounds

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Ren [Iowa State Univ., Ames, IA (United States)

    1999-02-12

    The syntheses of polycarbosilanes and polysilanes as silicon carbide ceramic precursors have been active research areas in the Barton Research Group. In this thesis, the work is focused on the preparation of polycarbosilanes and polysilanes as stoichiometric silicon carbide precursor polymers. The syntheses of the precursor polymers are discussed and the conversions of these precursors to silicon carbide via pyrolysis are reported. The XRD pattern and elemental analyses of the resulting silicon carbide ceramics are presented. Silicon monoxide is an important intermediate in the production of silicon metal. The existence of silicon monoxide in gap phase has been widely accepted. In the second part of this thesis, the generation of gaseous silicon monoxide in four different reactors and the reactions of gaseous silicon monoxide towards organic compounds are discussed.

  11. Structural studies of naturally occurring toxicogenic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Springer, J. P.

    1977-10-01

    The paralytic shellfish poison (PSP), saxitoxin, is a neurotoxin isolated from Alaska butter clams (Saxidomus giganteus), mussels (Mytilus californianus) and axenic cultures of the dinoflagellate Gonyaulax catenella. The structure of saxitoxin has been determined through the use of single crystal X-ray diffraction. It possesses a unique tricyclic arrangement of atoms containing two guanidinium moieties and also a hydrated ketone. The relative stereochemistry is presented as well as the absolute configuration. The chemical constitution of a tremorgenic metabolite, paxilline, isolated from extracts of the fungus Penicillium paxilli Bainier has been determined. Paxilline represents a previously unreported class of natural compounds formed by the combination of tryptophan and mevalonate subunits. The complete stereostructure of two other fungal metabolites, paspaline and paspalicine, closely related to paxilline but isolated from Claviceps paspali Stammes have also been determined and are presented. The stereochemistries of paxilline, paspaline and paspalicine are identical at corresponding chiral centers.

  12. [Studies on chemical compounds of Chlorella sorokiniana].

    Science.gov (United States)

    Zhang, Ling; Liu, Ping-huai; Wu, Jiao-na; Yang, Guo-fu; Suo, Yang-yang; Luo, Ning; Chen, Chen

    2015-04-01

    Chemical constituents of Chlorella sorokiniana were isolated and purified by repeated column chromatographies, over silicagel and Sephadex LH-20. Their structures were identified on the basis of physicochemical properties and spectroscopic data analysis. Five compounds were obtained from the petroleum ether extract of Chlorella sorokiniana, and their structures were identified as (22E, 24R)-5alpha, 3beta-epidioxiergosta-6, 22-dien-3beta-ol(1),(24S)-ergosta-7-en-3beta-ol(2), loliolide(3), stigmasta-7,22-dien-3beta,5alpha,6alpha-triol(4), and 3beta-hydroxy-5alpha,6alpha-epoxy-7-megastigmen-9-one(5). The main liposoluble fractions from Chlorella sorokiniana maiuly contain fatty acids, alkyl acids and olefine acids. Components 1-5 were isolated from the genus Chlorella for the first time.

  13. Experimental and theoretical studies of manganite and magnetite compounds Transition oxide compounds

    CERN Document Server

    Srinitiwarawong, C

    2002-01-01

    In the recent years interest in the transition oxide compounds has renewed among researchers in the field of condensed matter physics. This thesis presents the studies of the two families of the transition oxides, the manganite and magnetite compounds. Manganite has regained the interest since the discovery of the large magnetoresistance around its Curie temperature in 1990s. Magnetite on the other hand is the oldest magnetic material known to man however some of its physical properties are still controversial. The experimental works address some basic properties of these compounds when fabricated in the form of thin films. These include the resistivity measurements and magnetic measurements as well as the Hall effect. The various models of transport mechanism have been compared. The magnetic field and the temperature dependence of magnetoresistance have also been studied. Simple devices such as an artificial grain boundary and bilayers thin film have been investigated. The second part of this thesis concentr...

  14. An acoustic study of accentuation in Estonian Swedish compounds

    OpenAIRE

    Schötz, Susanne; Asu, Eva Liina

    2013-01-01

    This study, addressing the analysis of pitch patterns in Estonian Swedish compounds, enables us to draw some preliminary conclusions about the characteristics of accentuation in this little studied regional variety of Swedish. The analysis in the first part of the paper was inspired by the classification of Edvin Lagman (1979) who on the basis of auditory analysis distinguished between four accent types for Estonian Swedish compounds. Using the same materials, the present acoustic study broad...

  15. 31P NMR Study on Some Phosphorus-Containing Compounds

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    31P NMR has become a widely applied spectroscopic probe of the structure of phosphorus-containing compounds. Meanwhile, the application of 31P NMR has been rapidly expanded to biochemistry and medicinal chemistry of phosphorus-containing compounds because the growing importance of the phosphorus compounds is now widely realized. We report here the results of 31P NMR study on some phosphorus-containing compounds, namely, O-alkyl O-4-nitrophenyl methyl phosphonates with different alkyl chain-length (MePO-n), 4-nitrophenyl alkylphenylphosphinates with different alkyl chain-length (PhP-n), diethyl phosphono- acetonitrile anion and diethyl phosphite anion . Our results indicate that 31P NMR can not only be applied to not only the study of the hydrolytic reactions of MePO-8 and PhP-8 but also be applied to the study of the presence of the anions of diethylphosphonoacetonitrile and diethyl phosphite in nucleophilic reactions.

  16. Study of nonvolatile degradation compounds produced by radiosterilization of cefotaxime

    Science.gov (United States)

    Barbarin, N.; Tilquin, B.

    2001-01-01

    The effects of radiosterilization on the purity profile of cefotaxime were evaluated by a liquid chromatography-diode array method. Numerous new radiolytic compounds were detected in very small amount. They were quantified and it appeared that none was present above the level of 0.1% of the main compound and the total amount was only of 0.72%. Despite the low quantities present, some radiolytic compounds had UV spectra which could justify the apparition of a yellow coloration detected after irradiation. Others had UV spectra similar to that of cefotaxime, suggesting similarity in the molecular structures. Finally, some mechanisms of formation were proposed for four radiolytic compounds which were identified by mass spectrometry in a former study.

  17. Study of nonvolatile degradation compounds produced by radiosterilization of cefotaxime

    Energy Technology Data Exchange (ETDEWEB)

    Barbarin, N.; Tilquin, B. E-mail: tilquin@cham.ucl.ac.be

    2001-07-01

    The effects of radiosterilization on the purity profile of cefotaxime were evaluated by a liquid chromatography-diode array method. Numerous new radiolytic compounds were detected in very small amount. They were quantified and it appeared that none was present above the level of 0.1% of the main compound and the total amount was only of 0.72%. Despite the low quantities present, some radiolytic compounds had UV spectra which could justify the apparition of a yellow coloration detected after irradiation. Others had UV spectra similar to that of cefotaxime, suggesting similarity in the molecular structures. Finally, some mechanisms of formation were proposed for four radiolytic compounds which were identified by mass spectrometry in a former study. (author)

  18. Study of volatile compounds from the radiosterilization of solid cephalosporins

    Energy Technology Data Exchange (ETDEWEB)

    Barbarin, N.; Crucq, A.S.; Tilquin, B. [Universite Catholique de Louvain (UCL), Louvain-la-Neuve (Belgium)

    1996-12-01

    The use of {gamma}-rays is a promising method to sterilize thermosensitive drugs. Although radiosterilization does not modify drugs activity, this mode of sterilization produces new radiolytic products. This study is devoted to the analysis of volatile compounds which may induce a modification of odour. The volatile compounds produced by radiolysis of cefotaxime, cefuroxime and ceftazidime, three cephalosporins, were analyzed by gas chromatography with a headspace sampling. They were detected and identified by mass and infrared spectrometry. An explanation of their origin is proposed. (Author).

  19. New Approach for Fractioning Metal Compounds Studies in Soils

    Science.gov (United States)

    Minkina, Tatiana; Motuzova, Galina; Mandzhieva, Saglara; Bauer, Tatiana; Burachevskaya, Marina; Sushkova, Svetlana; Nevidomskaya, Dina; Kalinitchenko, Valeriy

    2016-04-01

    A combined approach for fractioning metal compounds in soils on the basis of sequential (Tessier, 1979) and parallel extractions (1 N NH4Ac, pH 8; 1% EDTA in NH4Ac; and 1N HCl) is proposed. Metal compounds in sequential and parallel extracts are grouped according to the strength of their bonds with soil components. A given group includes metal compounds with similar strengths of bonds and, hence, with similar migration capacities. The groups of firmly and loosely bound metal compounds can be distinguished. This approach has been used to assess the group composition of Zn, Cu, and Pb compounds in an ordinary chernozem and its changes upon the soil contamination with metals. Contamination of an ordinary chernozem from Rostov oblast with heavy metals caused a disturbance of the natural ratios between the metal compounds. In the natural soil, firmly bound metals predominate (88-95%of the total content), which is mainly caused by the fixation of metals in lattices of silicate minerals (56-83%of the total content). The mobility of the metals in the natural soil is low (5-12%) and is mainly related to metal compounds loosely bound with the soil carbonates. Upon the soil contamination with metals (application rates of 100-300 mg/kg), the content of all the metal compounds increases, but the ratio between them shifts towards a higher portion of the potentially mobile metal compounds (up to 30-40% of the bulk contents of the metals). Organic substances and non-silicate Fe, Al, and Mn minerals become the main carriers of the firmly and loosely bound metals. The strengths of their bonds with Cu, Pb, and Zn differ. Lead in the studied chernozems is mainly fixed in a loosely bound form with organic matter, whereas copper and zinc are fixed both by the organic matter and by the non-silicate Fe, Al, and Mn compounds. Firm fixation of the applied Cu and Pb is mainly ensured by the soil organic matter and non-silicate minerals, whereas firm fixation of Zn is mainly due to non

  20. Decomposition mechanisms of trinitroalkyl compounds: a theoretical study from aliphatic to aromatic nitro compounds.

    Science.gov (United States)

    Fayet, Guillaume; Rotureau, Patricia; Minisini, Benoit

    2014-04-14

    The chemical mechanisms involved in the decomposition of trinitroethyl compounds were studied for both aliphatic and aromatic derivatives using density functional theory calculations. At first, in the case of 1,1,1-trinitrobutane, used as a reference molecule, two primary channels were highlighted among the five investigated ones: the breaking of the C-N bond and the HONO elimination. Then, the influence of various structural parameters was studied for these two reactions by changing the length of the carbon chain, adding substituents or double bonds along the carbon chain. If some slight changes in activation energies were observed for most of these features, no modification of the competition between the two investigated reactions was highlighted and the breaking of the C-N bond remained the favoured mechanism. At last, the reactions involving the trinitroalkyl fragments were highlighted to be more competitive than reactions involving nitro groups linked to aromatic cycles in two aromatic systems (4-(1,1,1-trinitrobutyl)-nitrobenzene and 2-(1,1,1-trinitrobutyl)-nitrobenzene). This showed that aromatic nitro compounds with trinitroalkyl derivatives decompose from their alkyl part and may be considered more likely as aliphatic than as aromatic regarding the initiation of their decomposition process.

  1. Synthesis, structural and fungicidal studies of hydrazone based coordination compounds.

    Science.gov (United States)

    Sharma, Amit Kumar; Chandra, Sulekh

    2013-02-15

    The coordination compounds of the Co(II), Ni(II) and Cu(II) metal ions derived from imine based ligand, benzil bis(carbohydarzone) were structurally and pharmaceutically studied. The compounds have the general stoichiometry [M(L)]X(2) and [Co(L)X(2)], where M=Ni(II) and Cu(II), and X=NO(3)(-) and Cl(-) ions. The analytical techniques like elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, UV/Visible, NMR, ESI mass and EPR were used to study the compounds. The key IR bands, i.e., amide I, amide II and amide III stretching vibrations accounts for the tetradentate metal binding nature of the ligand. The electronic and EPR spectral results suggest the square planar Ni(II) and Cu(II) complexes (g(iso)=2.11-2.22) and tetragonal geometry Co(II) complexes (g(iso)=2.10-2.17). To explore the compounds in the biological field, they were examined against the opportunistic pathogens, i.e., Alternaria brassicae, Aspergillus niger and Fusarium oxysporum. The partial covalent character of metal-ligand bond is supported by the orbital reduction factor k (0.62-0.92) and nephalauxetic parameter β (0.55-0.57).

  2. Energetics of hydrogen bonding in proteins: a model compound study.

    OpenAIRE

    1996-01-01

    Differences in the energetics of amide-amide and amide-hydroxyl hydrogen bonds in proteins have been explored from the effect of hydroxyl groups on the structure and dissolution energetics of a series of crystalline cyclic dipeptides. The calorimetrically determined energetics are interpreted in light of the crystal structures of the studied compounds. Our results indicate that the amide-amide and amide-hydroxyl hydrogen bonds both provide considerable enthalpic stability, but that the amide-...

  3. Insilico studies of organosulfur-functional active compounds in garlic.

    Science.gov (United States)

    Singh, Yogendra P; Singh, Ram A

    2010-01-01

    Garlic has been used medicinally since antiquity because of its antimicrobial activity, anticancer activity, antioxidant activity, ability to reduce cardiovascular diseases, improving immune functions, and antidiabetic activities and also in reducing cardiovascular diseases and improving immune functions. Recent studies identify that the wide variety of medicinal functions are attributed to the sulfur compounds present in garlic. Epidemiological observations and laboratory studies in animal models have also showed anticarcinogenic potential of organosulfur compounds of garlic. In this study, in silico analysis of organosulfur compounds is reported using the methods of theoretical chemistry to elucidate the molecular properties of garlic as it is more time and cost efficient, reduces the number of wet experiments, and offers the possibility of replacing some animal tests with suitable in silico models. The analysis of molecular descriptors defined by Lipinski has been done. The solubility of drug in water has been determined as it is of useful importance in the process of drug discovery from molecular design to pharmaceutical formulation and biopharmacy. All toxicities associated with candidate drug have been calculated. P-Glycoprotein expressed in normal tissues as a cause of drug pharmacokinetics and pharmacodynamics has been examined. Drug-plasma protein binding and volume of distribution have also been calculated. To avoid rejection of drugs, it is becoming more important to determine pK(a), absorption, polar surface area, and other physiochemical properties associated with a drug, before synthetic work is undertaken. The present in silico study is aimed at examining these compounds of garlic to evaluate its possible efficacy and toxicity under conditions of actual use in humans.

  4. Antibacterial activities, DFT and QSAR studies of quinazolinone compounds

    Directory of Open Access Journals (Sweden)

    A. G. Al-Sehemi

    2016-08-01

    Full Text Available The quinazolinone compounds (1 and 2 in this work were examined for their in vitro antibacterial activities against gram-positive (Staphylococcus aureus and gram-negative bacteria (Klebsiella pneumonia, Proteus bacilli and Shigella flexneri. Compared to the reference antibiotic chloramphenicol, these compounds showed high antibacterial activities against studied strains with inhibition zones observation. The ground state geometries have been optimized by using density functional theory (DFT at B3LYP/6-31G* level of theory. The absorption spectra have been calculated by using time dependent density functional theory (TDDFT with and without solvent. The effect of different functionals (B3LYP, MPW1PW91, and PBE1PBE on the absorption wavelengths has been studied. The ionization potential (IP, electron affinity (EA, energy gap (Egap, electronegativity (χ, hardness (η, electrophilicity (ω, softness (S and electrophilicity index (ωi were computed and discussed. The nonlinear optical (NLO properties vary by changing the theory (DFT to HF or functional (B3LYP to CAM-B3LYP. The physicochemical parameters have been studied by quantitative structure–activity relationship (QSAR. The computed properties of investigated compounds have been compared with the Chloramphenicol as well as available experimental data.

  5. Study on Effect of Compounding Sulfurized Isobutylene with Thioester

    Institute of Scientific and Technical Information of China (English)

    Li Hongjun; Qiu Yansheng

    2002-01-01

    Oxygen is introduced into the sulfurized isobutylene by compounding the sulfurized isobutylene with thioester. This paper studies the synergistic effect of commingling the sulfurized isobutylene with thioester during testing in the four-ball machine and the high-speed Timken machine. Tests in the four-ball machine and the high-speed Timken machine have revealed an improvement in EP performance of sulfurized isobutylene in admixture with thioester. The interfacial tension test and electrochemical analysis of anodic polarization have discovered increase of adsorptive force of the additive package on metal surface following compounding sulfurized isobutylene with thioester. The XPS and AES analyses indicate to the formation of FeS, Fe203 and FeSO4 on the metal surface. The sulfurized film formed by the additive package on the metal surface is thicker than that formed by simple sulfurized isobutylene.

  6. Quantum chemical studies of photochromic properties of benzoxazine compound

    Energy Technology Data Exchange (ETDEWEB)

    Toliautas, Stepas, E-mail: stepas.toliautas@ff.stud.vu.lt [Department of Theoretical Physics, Vilnius University, Sauletekio 9-III, LT-10222 Vilnius (Lithuania); Sulskus, Juozas, E-mail: juozas.sulskus@ff.vu.lt [Department of Theoretical Physics, Vilnius University, Sauletekio 9-III, LT-10222 Vilnius (Lithuania); Valkunas, Leonas, E-mail: leonas.valkunas@ff.vu.lt [Department of Theoretical Physics, Vilnius University, Sauletekio 9-III, LT-10222 Vilnius (Lithuania); Institute of Physics, Center for Physical Sciences and Technology, Savanoriu 231, LT-02300 Vilnius (Lithuania); Vengris, Mikas, E-mail: mikas.vengris@ff.vu.lt [Department of Quantum Electronics, Vilnius University, Sauletekio 9-III, LT-10222 Vilnius (Lithuania)

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Photochromic indolo-benzoxazine compound is studied. Black-Right-Pointing-Pointer Advanced LC-TDDFT and GMC-QDPT methods are used for excited state calculations. Black-Right-Pointing-Pointer Oxazine ring opens upon UV light excitation. Black-Right-Pointing-Pointer Fragments of the compound assume structures similar to the ions of separate molecules. Black-Right-Pointing-Pointer Multiple pathways of the photo-induced reaction are expected. -- Abstract: Molecular electronic structure of ground and excited states of a photochromic indolo[2,1-b][1,3]benzoxazine compound incorporating closed-ring system, which opens upon UV light excitation, was studied using various quantum chemical methods. Three local minima of the ground electronic state potential energy surface and related transition states were identified along the path of rotation of 4-nitrophenol group. Additionally, three local minima of the excited electronic states were located. The evaluated transition energy barriers between local ground-state minima nearest to the initial structure of the investigated molecule are less than 2 k{sub B}T, making open structures likely to revert to the initial structure by thermalization. Results obtained using ab initio GMC-QDPT method were explored and compared to the widely used TD-DFT and semi-empiric ZINDO methods.

  7. Study of Coumarin-Resveratrol Hybrids as Potent Antioxidant Compounds

    Directory of Open Access Journals (Sweden)

    Maria J. Matos

    2015-02-01

    Full Text Available In the present work we synthesized a selected series of hydroxylated 3-phenylcoumarins 5–8, with the aim of evaluating in detail their antioxidant properties. From an in depth study of the antioxidant capacity data (ORAC-FL, ESR, CV and ROS inhibition it was concluded that these derivatives are very good antioxidants, with very interesting profiles in all the performed assays. The study of the effect of the number and position of the hydroxyl groups on the antioxidant activity was the principal aim of this study. In particular, 7-hydroxy-3-(3'-hydroxyphenylcoumarin (8 proved to be the most active and effective antioxidant of the selected series in four of the performed assays (ORAC-FL = 11.8, capacity of scavenging hydroxyl radicals = 54%, Trolox index = 2.33 and AI30 index = 0.18. However, the presence of two hydroxyl groups on this molecule did not increase greatly the activity profile. Theoretical evaluation of ADME properties of all the derivatives was also carried out. All the compounds can act as potential candidates for preventing or minimizing the free radical overproduction in oxidative-stress related diseases. These preliminary findings encourage us to perform a future structural optimization of this family of compounds.

  8. Quantum Mechanical Studies of the Early Actinide Compounds

    Science.gov (United States)

    Obodo, Kingsley Onyebuchi

    This study involves the investigation of the early actinide systems using ab initio techniques based on density functional theory (DFT). It was motivated by: (i) the incomplete description of these systems using conventional DFT because they are strongly correlated, (ii) the usefulness of these systems in nuclear energy generation, (iii) the complexity that arises in experimentally studying these systems due to their inherent radioactive nature and (iv) their limited availability. The results obtained from this study are divided into two broad sections. The first comprises chapters 3 and 4 while the second comprises chapters 5 and 6. Thorium based compounds are studied in chapters 3 and 4. In the first section, the Hubbard U parameter is not necessary to accurately describe the electronic, elastic and mechanical properties of these systems. In the second, the inclusion of the Hubbard U parameter is shown to be paramount for the accurate description of most compounds considered. Chapter 3 presents the electronic, structural and bonding character of thorium based nitrides. We obtained the result that Th2N2 NH, which is crystallographically equivalent to metallic Th2N 3, is insulating. Chapter 4 demonstrates that the formation of a meta-stable thorium-titanium based alloy is plausible and also further information on bonding, electronic and elastic properties of the determined meta-stable alloy is provided. This has provided important new knowledge about these bulk systems. In Chapter 5 the DFT + U based study on Pa and its oxides is presented. The electronic, structural and bonding character of these systems was studied. We found that PaO2 is a Mott-Hubbard insulator with an indirect band gap of 3.48 eV within the generalized gradient approximation GGA + U. Chapter 6 discusses various actinide nitrides. We explored the electronic properties, elastic properties, lattice dynamics and the energetics of the various compounds using GGA + U. Also, we investigated the effect

  9. A preliminary study of periodontitis and vascular calcification compound model

    Institute of Scientific and Technical Information of China (English)

    MENGYun; DENGJing; PanKe-qing

    2015-01-01

    Objective This experiment is desired to establish a compound model of chronic periodontitis and vascular calcification,so as to study the relation of periodontal and vascular calcification.Methods Forty male Wistar rats were randomly divided into:control group(group C),periodontitis group(group CP),vascular calcification group(group VDN),compound group (group CP+VDN).Every groups accepted the corresponding manages to establish the animal model.Eight weeks later,al the rats were sacrificed and the fol owing items were observed:inflam-matory factor in serum were tested,Hematoxylin-eosin staining(HE)staining of vascular tissue were taken to test.Results Through detection of periodontal tissue,serum and vascular tissue,an-imal models were successful.Histopathologic observation revealed:obvious inflammation of periodontal tissue was obversed in group CP and CP+VDN.The red Mineralized nodules deposition in group VDN and CP+VDN were higher than in group C and CP(P<0.05)by HE staining,and that in group CP+VDN was significantly higher than in group VDN(P<0.05);Animals in group CP+VDN showed higher level of IL-1 in serum than that in group CP,VDN and C.Conclusion This study has demonstrated that periodontitis have some promoting ef ect on vascular cal-cification.

  10. Study a compound orthorhombic lattice pattern in dielectric barrier discharge

    Science.gov (United States)

    Wang, Hao; Dong, Lifang; Gao, Xing; Liu, Weibo; Wei, Lingyan; Pan, Yuyang

    2016-12-01

    The compound orthorhombic lattice pattern which is composed of the bright spot and the dim spot is observed for the first time in a dielectric barrier discharge system. It is found that the dim spot is located at the gravity center of the surrounding three bright spots. The discharge bifurcates from a square lattice, hexagon pattern to compound orthorhombic lattice pattern and finally changes to an irregular pattern. The phase diagram of the pattern types as a function of the applied voltage and the argon concentration is given. The spatio-temporal dynamics of the pattern is studied by the time correlation measurement and the high speed video camera images. Results show that the dim spot is formed by both volume discharge and surface discharge induced by the bright spot. The differences of plasma parameters between the bright spots and the dim spots obtained by optical emission spectroscopy verify that the dim spot is formed by both volume discharge and surface discharge. To better understand the mechanism of firing of the dim spots for the same conditions as in the first phase diagram, the phase diagram of the mechanism of firing of the dim spots as a function of the gas pressure and the argon concentration is given. The simulation of the electric fields of wall charges accumulated by bright spots further verifies that the bright spot has an effect on the formation of dim spot.

  11. Study on Antibiotic compounds from Pseudomonas aeruginosa NO4 Strain

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ji Young; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2011-05-15

    As important human and veterinary medicines, antibiotics are being produced and consumed in large quantities around the world. For example, more than 50 million pounds (22,000 tons) of antibiotics are produced in the U.S. each year and annual production in Germany is about 2,000 tons. Antibiotics are low molecular weight microbial metabolites that at low concentrations inhibit the growth of other microorganisms. Resistant bacteria may also spread and become broader infection-control problems, not only within health care institutions, but in communities as well. Clinically important bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). MRSA is a common cause of infection among hospitalized patients. Pseudomonas aeruginosa is a major cause of opportunistic infections among immunocompromised individuals. The spread of this organism in health care settings is often difficult to control due to the presence of multiple intrinsic and acquired mechanisms of antimicrobial resistance. In this study, we isolated novel bacterium which had strong antagonistic activity and separated antibiotic compounds from Pseudomonas sp., and analyzed characteristics and molecular weight of the antibiotic compound

  12. High pressure optical studies of crystalline anils and related compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hockert, E.N.; Drickamer, H.G.

    1977-12-01

    High pressure optical studies have been made on a series of crystalline therochromic and photochromic anils and model compounds. Measurements include absorption and emission peak locations and the integrated intensities of various absorption peaks including the uv peak and visible peaks introduced thermally or by irradiation at various temperatures and pressures. Emission yields were also obtained. For the thermochromic compounds there was a large increase in the equilibrium yield of the thermally induced peak with pressure (piezochromism), corresponding to a volume decrease of approx.1.2 cc/mole for 5-bromosalicylidene aniline (5BrSA). The emission peak shifts to lower energy and decreases in intensity primarily because of increased rate of the radiationless conversion. For salicylidene aniline and related photochromic crystals the rate of photochromic conversion varied with both pressure and temperature in a manner which depends on the size of the energy barriers to the forward and reverse processes. The emission yield increases with pressure at low pressure, goes through a maximum, and decreases at high pressure. At low pressure the dominant feature is increase in occupation of the emitting state while at high pressure the increased rate of the radiationless process governs. For 2- (O-hydroxyphenyl) benzoxazole (OHBO) (see Fig. 1), where a keto--enol rearrangement is most probable, the changes in absorption and emission intensity can be related to the same diagram used for the anils. This diagram also describes the behavior of benzilidene aniline (BA), where only a cis--trans isomerization is possible.

  13. A Study of Compound Solar Eruption in NOAA AR11429

    Science.gov (United States)

    Zhang, Jie; Dhakal, Suman Kumar

    2017-08-01

    We analyze and report a compound eruption process associated with an M8.4 flare occurred on March 10, 2012 in NOAA AR 11429. In the main phase of the flare, there were two major peaks in GOES X-ray at ~17:20 UT and ~ 17:40 UT respectively. We found that the two flare peaks, separated by about 20 minutes, corresponded to two individual erupting magnetic flux bundles from the same active region and along the same magnetic polarity inversion line. The erupting features were seen as a hot channel-like structure of a temperature of ~ 10 MK in coronal images obtained from SDO AIA 131 A passband. We believe that each erupting feature is originated from an individual magnetic flux bundle. Prior to the onset of the eruption, the magnetic structure of the source region likely contains a double decker configuration, i.e., a coherent flux bundle lies above another coherent flux bundle. The upper bundle became unstable and started to erupt. Shortly after, the lower bundle started to accelerate and merged with the upper bundle, forming a single CME as seen in coronagraph images. This study demonstrates that complex magnetic configuration could form in the corona and result in a compound solar eruption that involves energy release in different magnetic structures. We will discuss the physical processes that inter-connect multiple magnetic structure in an active region.

  14. Compound sawtooth study in ohmically heated TFTR plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, H.; McGuire, K.; Colchin, D.; Efthimion, P.C.; Fredrickson, E.; Hill, K.; Kiraly, J.; Pare, V.; Taylor, G.; Sauthoff, N.

    1985-09-01

    Compound sawtooth activity has been observed in ohmically heated, high current, high density TFTR plasmas. Commonly called ''double sawteeth,'' such sequences consist of a repetitive series of subordinate relaxations followed by a main relaxation with a different inversion radius. The period of such compound sawteeth can be as long as 100 msec. In other cases, however, no compound sawteeth or bursts of them can be observed in discharges with essentially the same parameters.

  15. Study on compound ultra-precision alignment technique

    Institute of Scientific and Technical Information of China (English)

    Zhang Jinlong; Yang Ankang; Liu Jingnan; Yoshiyuki Uchida

    2007-01-01

    A nano-displacement measurement system with duo-gratings is analyzed by using optics theory, a mathematic model for the system is established, and the characteristic of laser Moiré signals is studied through CAD simulation. To improve signal sensitivity and positioning accuracy, two methods of precision positioning are brought forward: differential Moiré positioning method and modified Moiré positioning method. A compound control system for precision positioning is set up by combining these 2 Moiré alignment methods, in which the modified Moiré alignment technique is used for coarse alignment and the differential Moiré alignment technique is used for fine alignment, and the system obtains positioning accuracy of ±10 nm in ±500 μm positioning range with shot response time.

  16. Physiological and Histopathological studies on Bisphenol-A compound as

    Directory of Open Access Journals (Sweden)

    Eman G.E.Helal *; Mohamed M.M. Badawi **; Maha G. Soliman *; Nadia A. Abdel-Kawi *; Hewaida A. E. Fadel ***; Nashwa M. G. Abozaid

    2013-01-01

    Full Text Available Back ground: Xenoestrogens are compounds like estrogens in effect but not in structure which are mimicking the action of endogenous estrogen and activate estrogen receptor. Xenoestrogens are chemically distinct industrial products potentially able to disrupt the endocrine system by mimicking the action of endogenous steroid hormones. Among such compounds, the ubiquitous environmental contaminants bisphenol-A (BPA may promote adverse effects in humans triggering estrogenic signals in target tissues. Bisphenol- A is widely used in food and drinks packaging. Aim of the work: The present study is carrying out to evaluate the effect of bisphenol-A on sexual hormonal pattern in male albino rats. Material and Methods: 64adult male Sprague – Dawley rats (100-120 g were divided to four groups (16 rats/group.Group (1: control group without any treatment. Group(2: positive control group was injected subcutaneously (s.c with sesame oil daily. Group (3: received BPA daily with low dose (10 mg/kg/day s.c. Group (4: received BPA daily with high dose (30 mg/kg/day s.c. The experiment durated 30 days, half rats of each group were sacrificed after 15 days of treatment and the other half of groups after 30 days. The blood was collected, serum was separated and used for estimation of (hormonal levels, prolactin, gonadotrophin and testosterone and some biochemical parameters (liver enzymes, kidney function, protein and lipid profile. Testis, liver and kidney were taken for the histopathological examination. Results: Biochemical results showed significant elevation in prolactin and FSH levels and significant reduction in LH and testosterone levels in all groups compared to the control group. Increased serum enzymes (ASAT, ALAT& ALP levels with increased concentration of urea and creatinine were detected in all the treated groups compared to the control group. Decline in protein profile and elevation in the concentration of lipid profile, while HDL was decreased in

  17. Study on apatite compounds; Apataitokei kagobutsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-28

    To clarify the material properties of apatite compounds, the synthesis method, and the evaluation of physical properties of material and elementary technology were investigated. For the study on synthesis and crystal growth, a method of precipitating calcium phosphate on the surface of metal was investigated by means of relatively mild electrolytic method using liquid phase system. A new molding method of Ca defective apatite was established. Composite similar to vital bone was prepared by means of a new low-temperature sintering. For the study on chemical properties, from the model experiments, it was found that the self-organizing phenomenon, which is observed in the composite of apatite and collagen, happened between the organic single molecular film and crystal of apatite. For the study on evaluation of physical properties and elementary technology, the surface and interface of ceramics such as apatite were investigated by means of spectroscopy, the electronic state was analyzed by the quantum chemical calculation, and the crystalline structure was analyzed using X-ray equipment. 270 refs., 102 figs., 10 tabs.

  18. Mechanistic Study of Oxygen Atom Transfer Catalyzed by Rhenium Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Xiaopeng Shan

    2003-08-05

    Two ionic and one neutral methyl(oxo)rhenium(V) compounds were synthesized and structurally characterized. They were compared in reactivity towards the ligands triphenylphosphane, pyridines, pyridine N-oxides. Assistance from Broensted bases was found on ligand displacement of ionic rhenium compounds as well as nucleophile assistance on oxidation of all compounds. From the kinetic data, crystal structures, and an analysis of the intermediates, a structural formula of PicH{sup +}3{sup -} and mechanisms of ligand displacement and oxidation were proposed.

  19. Study on the Reaction of Benzimidazolium Salt with Amine Compounds

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The addition-hydrolysis reaction of benzimidazolium salt with some mono- andbifunctional amine nucleophiles is reported, and a novel method of biomimetic synthesis forformamides and heterocycle compounds is provided.

  20. studies on transition metal complexes of herbicidal compounds. ii

    African Journals Online (AJOL)

    a

    II: TRANSITION METAL COMPLEXES OF DERIVATIZED 2-CHLORO-4- ... Several compounds of this class like atrazine, simazine, prometryn, aziprotryn, etc. .... dissolve in water and most of the common polar organic solvents. ... coordination.

  1. Theoretical Study on the High Energy Density Compound Hexanitrohexaazatricyclotetradecanedifuroxan

    Institute of Scientific and Technical Information of China (English)

    QIU Ling; XIAO He-Ming; ZHU Wei-Hua; JU Xue-Hai; GONG Xue-Dong

    2006-01-01

    Density functional theory (DFT) has been employed to study the molecular geometries, electronic structures,infrared (IR) spectra, and thermodynamic properties of the high energy density compound hexanitrohexaazatricyclotetradecanedifuroxan (HHTTD) at the B3LYP/6-31G** level of theory. The calculated results showthattherearefourconformationalisomers (a, β, γ and δ) for HHTTD, and the relative stabilities of four conformers were assessed based on the calculated total energies and the energy-gaps between the frontier molecular orbitals. The computed harmonic vibrational frequencies are in reasonable agreement with the available experimental data. Thermodynamic properties derived from the IR spectra on the basis of statistical thermodynamic principles are linearly correlated with the temperature. Detonation performances were evaluated by using the Kamlet-Jacobsequationsbasedonthecalculated densities and heats of formation. It was found that four HHTTD isomers with the predicted densities of ca. 2 g·cm-3, detonation velocities near 10 km·s-1, and detonation pressures over 45 Gpa, may be novel potential candidates of high energy density materials (HEDM). These results may provide basic information for the molecular designof HEDM.

  2. Theoretical study of ionization potentials of N-heterocyclic compounds

    Directory of Open Access Journals (Sweden)

    Liudmyla K. Sviatenko

    2014-12-01

    Full Text Available The ability to predict the redox properties is an important tool for study electron transfer processes occurring in the gas-phase (atmospheric chemistry or in the condensed phase (electrochemistry, biochemistry. MPWB1K/6-31+G(d and MPWB1K/tzvp theoretical models were found to provide reasonable accuracy of the prediction of ionization potentials for mono- and polycyclic azacompounds. The root mean square errors of the methods are 0.19 and 0.20, respectively. While the mean absolute deviation for both methods is the same and equals to 0.15 eV. These theoretical models were applied to predict ionization potentials for compounds not evaluated experimentally. Influence of substitutes and a number of nitrogen atoms on value of ionization potential was analyzed. Methyl-, and phenyl- groups, and fused benzo cycle decrease ionization potentials of N-heterocycles. Increase of amount of nitrogen atoms in five-membered cycles leads to significant enlargement of ionization potentials.

  3. Low-temperature NMR studies of Ce-Al compounds

    Energy Technology Data Exchange (ETDEWEB)

    Gavilano, J.L. (Laboratorium fuer Festkoerperphysik, ETH-Hoenggerberg, CH-8093 Zuerich (Switzerland)); Hunziker, J. (Laboratorium fuer Festkoerperphysik, ETH-Hoenggerberg, CH-8093 Zuerich (Switzerland)); Vonlanthen, P. (Laboratorium fuer Festkoerperphysik, ETH-Hoenggerberg, CH-8093 Zuerich (Switzerland)); Ott, H.R. (Laboratorium fuer Festkoerperphysik, ETH-Hoenggerberg, CH-8093 Zuerich (Switzerland))

    1994-04-01

    Ce-Al compounds display a variety of unconventional magnetic properties at low temperatures. This is particularly well demonstrated by the results of our low-frequency NMR studies on CeAl[sub 2], CeAl[sub 3] and Ce[sub 3]Al[sub 11]. Although CeAl[sub 2] orders antiferromagnetically below 3.4 K, the temperature dependence of the spin-lattice relaxation rate follows a Korringa law below 1 K. For CeAl[sub 3], we observe an increase of the line width below 0.9 K, but no indication of a phase transition is discernible from the temperature dependence of the spin-lattice relaxation rate. Ce[sub 3]Al[sub 11] is ferromagnetic below 6.2 K, but develops an antiferromagnetic and modulated structure below 3.3 K. A field of the order of 3 kG, however, appears to stabilize the ferromagnetic phase. Our spectroscopic data are important in view of some of the unusual thermal properties of these materials. ((orig.))

  4. Mechanistic Study of the Acid Degradation of Lignin Model Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Sturgeon, M.; Kim, S.; Chmely, S. C.; Foust, T. D.; Beckham, G. T.

    2012-01-01

    Lignin is a major constituent of biomass, which remains underutilized in selective biomass conversion strategies to renewable fuels and chemicals. Here we are interested in understanding the mechanisms related to the acid deconstruction of lignin with a combined theoretical and experimental approach. Two model dimers with a b-O-4 aryl ether linkage (2-phenoxy-1-phenethanol and 2-phenoxy-1-phenyl-1,3 propanediol) and model dimmers with an a-O-4 aryl ether linkage were synthesized and deconstructed in H2SO4. The major products of the acidolysis of the b-O-4 compounds consisted of phenol and two aldehydes, phenylacetaldehyde and benzaldehyde. Quantum mechanical calculations were employed to elucidate possible deconstruction mechanisms with transition state theory. To confirm proposed mechanisms several possible intermediates were studied under similar acidolysis conditions. Although the resonance time for cleavage was on the order several hours, we have shown that the cleavage of the aryl ether linkage affords phenol and aldehydes. We would next like to utilize our mechanism of aryl ether cleavage in actual lignin.

  5. Bridging Language and Culture: A Cognitive Approach to the Study of Chinese Compounds.

    Science.gov (United States)

    Liu, Jennifer

    1992-01-01

    Culturally specific compounds in Chinese could be more effectively studied from a cognitive approach, using the underlying idealized cognitive models defined by Lakoff. It is argued that the formation of Chinese compounds are systematically guided by idealized cognitive models and compounds are semantically compositional. (seven references) (LB)

  6. Studies on the amide compounds ofMirabilis. Jalapa. L

    Institute of Scientific and Technical Information of China (English)

    SHEN; XuWei

    2001-01-01

    Mirabilis himalaica(Edgew.)Heinerl Var. Chinensis Heimerl belonging to the genus Mirabilis are used in chinese medicine as a remedy for various diseases[1].Its chemical constituents,however, have not been reported so far. we have carried out a detailed chemical investigatigation of the seeds and have isolated two new amides along with three known compounds.  The known compounds were identified by comparing their spectral data with those of authentic samples or with those reported in literature as daucosterol[2], bsitoserol[2], boeravinone E[3], in the present note, the structural elucidation of two new amides is reported.  ……

  7. Studies on the amide compounds ofMirabilis. Jalapa. L

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Mirabilis himalaica(Edgew.)Heinerl Var. Chinensis Heimerl belonging to the genus Mirabilis are used in chinese medicine as a remedy for various diseases[1].Its chemical constituents,however, have not been reported so far. we have carried out a detailed chemical investigatigation of the seeds and have isolated two new amides along with three known compounds. The known compounds were identified by comparing their spectral data with those of authentic samples or with those reported in literature as daucosterol[2], bsitoserol[2], boeravinone E[3], in the present note, the structural elucidation of two new amides is reported.

  8. STUDIES ON THE SENSITIZATION OF ANIMALS WITH SIMPLE CHEMICAL COMPOUNDS

    Science.gov (United States)

    Landsteiner, K.; Di Somma, A. A.

    1940-01-01

    Sensitization of guinea pigs to picric acid was obtained by application of oil solutions to the skin, preferably on inflamed sites or by treatment with a compound of picric acid with n-butyl-p-aminobenzoate. The lesions obtained in sensitive animals on superficial administration bore resemblance to human eczema. It seems probable that picric acid sensitization is an instance where a substance does not sensitize directly but after conversion into a more reactive compound, a principle which should be of wider application to instances where the original substance does not readily form conjugates. PMID:19871030

  9. Moessbauer spectroscopic study on inorganic compounds. Pt. 2

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Masashi; Kitazawa, Takafumi; Nanba, Hiroshi; Yoshinaga, Tomohiro; Nakajima, Norio; Sumisawa, Yasuhiro; Takeda, Masuo [Toho Univ., Funabashi, Chiba (Japan). Faculty of Science; Sawahata, Hiroyuki; Ito, Yasuo

    1998-01-01

    {sup 166}Er and {sup 127}I Moessbauer spectra were observed. {sup 166}Er Moessbauer spectrum of Er metal and 9 compounds were measured by {sup 166}Ho/Y{sub 0.6}Ho{sub 0.4}H{sub 2} source at 12K and the parameters such as e{sup 2}qQ(mm s{sup -1}), Heff(T) and {tau}(ns) were determined. The relaxation time of ErCl{sub 3}{center_dot}6H{sub 2}O was 0.7ns, long, but that of ErCl{sub 3} was 10 ps, short time. {sup 127}I Moessbauer spectrum of PhI(O{sub 2}CR){sub 2} (R=CH{sub 3}, CHF{sub 2}, CH{sub 2}Cl, CHCl{sub 2}, CCl{sub 3}, CH{sub 2}Br, CHBr{sub 2} and CBr{sub 3}) were observed and compared with that of R`{sub 3}Sb(O{sub 2}CR){sub 2} was similar to that of PhI(O{sub 2}CR){sub 2}. The correlation coefficient between e{sup 2}qQ({sup 127}I) and Mulliken population of carboxylic hydrogen atom of R{sub 2}CO{sub 2}H was -0.87. The relation between the hypervalent bond of O-I-O and that of O-Sb-0 was shown by the equation: e{sup 2}qQ({sup 121}Sb)/mm s{sup -1} = -47.2 + 1.32 e{sup 2}qQ({sup 127}I)/mm s{sup -1}. Hypervalent iodine complex such as (PhI(py){sub 2}){sup 2+} salt and E-Sb-I (E=O, I, N and C) were studied, too. (S.Y.)

  10. NMR study of magnetic fluctuations in 115 actinide compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kambe, S. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan)]. E-mail: kambe.shinsaku@jaea.go.jp; Sakai, H. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Tokunaga, Y. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Kato, H. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Fujimoto, T. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Walstedt, R.E. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Ikeda, S. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Matsuda, T.D. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Haga, Y. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki 319-1195 (Japan); Aoki, D. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Homma, Y. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Shiokawa, Y. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Onuki, Y. [Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

    2007-03-15

    We report NMR measurements in isostructural compounds (HoCoGa{sub 5}: 115 type) AnTGa{sub 5} (An: U, Np and Pu, T: Fe, Co and Pt) with different ground states (paramagnet, antiferromagnet and superconductor) using single crystal samples. The electrical field gradient at the Ga and Co sites are similar in all compounds, indicating that the charge distribution around these sites is determined mainly by intra-atomic orbitals. In contrast, the hyperfine coupling constants at the Ga and Co sites depend on the compounds considerably. Since the hyperfine coupling at the ligand sites is a transferred hyperfine coupling due to hybridization between 5f and ligand orbitals, it is natural that the hyperfine coupling constant depends on the 5f electronic states. Spin-lattice relaxation rates (1/T{sub 1}) in the paramagnetic state show more drastic differences between the compounds. In the antiferromagnets UPtGa{sub 5}, NpFeGa{sub 5} and NpCoGa{sub 5}, 1/T{sub 1}T shows a Curie-Weiss behavior at high temperatures, indicating a strong localized character. By contrast, in the paramagnet UFeGa{sub 5}1/T{sub 1}T is small and almost independent of T, indicating an ordinary metallic state with weak exchange enhancement. Finally, in the superconductor PuRhGa{sub 5} the magnitude of 1/T{sub 1}T lies between those of the antiferromagnets and the paramagnet.

  11. Chemical studies on the nonlinear optics of coordina- tion compounds

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The exploration of molecule-based nonlinear optical (NLO) materials at the molecular level is one of the novel areas developed recently from the viewpoint of chemistry. This review summarizes some of our recent researches on new NLO materials based on coordination compounds, which may have potential applications in optical devices.

  12. Diffusion in intermetallic compounds studied using short-lived radioisotopes

    CERN Multimedia

    Diffusion – the long range movement of atoms – plays an important role in materials processing and in determining suitable applications for materials. Conventional radiotracer methods for measuring diffusion can determine readily how distributions of radioactive probe atoms in samples evolve under varying experimental conditions. It is possible to obtain limited information about atomic jump rates and pathways from these measurements; however, it is desirable to make more direct observations of the atomic jumps by using experimental methods that are sensitive to atomic scale processes. One such method is time-differential perturbed $\\gamma$–$\\gamma$-angular correlation spectroscopy (PAC). Two series of PAC experiments using $^{111m}$Cd are proposed to contribute to fundamental understanding of diffusion in intermetallic compounds. The goal of the first is to determine the dominant vacancy species in several Li$_{2}$-structured compounds and see if the previously observed change in diffusion mechanism th...

  13. Theoretical Study of Some Nitrososulfamide Compounds with Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Madi Fatiha

    2004-09-01

    Full Text Available The lowest-energy conformations of four 2-chloroethylnitrososulfamides were determined using the MM+ molecular mechanics method as implemented in Hyperchem 6.0. Some of the calculated structural parameters, angles and bonds lengths were compared with the crystal structure data of N-nitroso-N-(2-chloroethyl-N’-sulfamoyl- proline. Using MM+, AM1 and PM3 the anti conformation was predicted to be more stable than the syn conformation in each of these compounds. With these methods we found that the relative energy of the transition state (TS was considerably higher, but with the ab initio method using RHF with minimal basic function STO-3G we found that the syn conformation is predicted to be slightly more stable. The determination of some atomic charges of a selection of atoms on the syn, anti and TS structures of the various compounds provided some details about the nature of the transition state.

  14. Dielectric relaxation and birefringence study of 7.O5O.7 dimeric liquid crystal compound

    Science.gov (United States)

    Bhattacharjee, Debanjan; Paul-Choudhury, Sandip; Alapati, Parameswara Rao; Bhattacharjee, Ayon

    2016-05-01

    Measurement of dielectric relaxation and birefringence phenomenon of dimeric liquid crystal compound with the dependence of temperature was reported in this paper. Homogeneous (HG) and homeotropic (HT) alignment of the cell are introduced to investigate the dielectric relaxation, activation energy and birefringence. Cole-Cole plots analyzed the dielectric relaxation of the dimeric compound. The observed Cole-Cole plots were semi-circular, and the relaxation mechanism obeys the non-Debye type of relaxation behaviour. Slater's perturbation equations have been used to analysis the activation energy of the compound. The birefringence of the compound has positively anisotropy and thin prism mechanism was used to study the anisotropy of the compound.

  15. Theoretical Study of the Compound Parabolic Trough Solar Collector

    Directory of Open Access Journals (Sweden)

    Dr. Subhi S. Mahammed

    2012-06-01

    Full Text Available Theoretical design of compound parabolic trough solar collector (CPC without tracking is presented in this work. The thermal efficiency is obtained by using FORTRAN 90 program. The thermal efficiency is between (60-67% at mass flow rate between (0.02-0.03 kg/s at concentration ratio of (3.8 without need to tracking system.The total and diffused radiation is calculated for Tikrit city by using theoretical equations. Good agreement between present work and the previous work.

  16. Study on quality control method for compound Shanzha Granules

    Institute of Scientific and Technical Information of China (English)

    付延伟; 程艳芹

    2015-01-01

    Objective:To establish the quality standard of Compound Shanzha Granules. Methods:Crataegi Fructus and Cassiae Semen were identified by TLC. The contents of Autrantio- obtusin and Chrysophanol in Cassiae Semen were determined by HPLC. Results:The relevant spots on TLC plates were clear by the blank reference. The contents showed good linearitis in the range of 0.0357~0.3570μg for Autrantio- obtusin and 0.0520~0.5200μg for Chrysophanol.Conclusions:The method are simple, accurate and reproducible.

  17. Study on Photocatalytic Degradation of Endocrine Disrupting Compound

    Science.gov (United States)

    Pralhad Parihar, Bhagwan; Gupta, Smita; Chakraborty, Mousumi

    2017-07-01

    Propylparaben (PP) is catagorized as endocrine disrupting compounds and is found to be present in urban wastewater comparatively at high concentrations. In the present work, propylparaben was degraded photo-catalytically by optimizing different process parameters such as initial concentration of propylparaben (25mgL-1 to 100 mgL-1), pH of the feed phase and concentration of photocatalyst TiO2 (50 mgL-1 to 200 mgL-1). Finally PP degraded and converted to CO2 and H2O and the degradation was found to follow the first order kinetics.

  18. 14N NQR study of nicotinamide and related compounds.

    Science.gov (United States)

    Seliger, J; Zagar, V

    2008-01-01

    14N nuclear quadrupole resonance (NQR) frequencies have been measured in picolinamide, nicotinamide, isonicotinamide, 2,6-pyridine dicarboxamide, and acetamide by double resonance. The 14N NQR spectra in picolinamide, nicotinamide, isonicotinamide, and 2,6-pyridine dicarboxamide show the presence of two distinct nitrogen positions: the ring position with the quadrupole coupling constant about 4,5 MHz and the amide position with the quadrupole coupling constant about 2.6 MHz. The NQR data are related to the structure of the investigated compounds and to the N--H...O hydrogen bonds.

  19. Studies on the antioxidant activities of some new chromone compounds.

    Science.gov (United States)

    Kładna, Aleksandra; Berczyński, Paweł; Piechowska, Teresa; Kruk, Irena; Aboul-Enein, Hassan Y; Ceylan-Unlusoy, Meltem; Verspohl, Eugen J; Ertan, Rahmiye

    2014-11-01

    Recent reviews evidence that the naturally occurring compounds containing the chromone skeleton exhibit antiradical activities, providing protection against oxidative stress. The antioxidant activities of 13 new synthesized chromonyl-2,4-thiazolidinediones, chromonyl-2,4-imidazolidinediones and chromonyl-2-thioxoimidzolidine-4-ones were evaluated using in vitro antioxidant assays, including superoxide anion radical (O2(-•)), hydroxyl radical (HO(•)), 2,2-diphenyl-1-picryl-hydrazyl free radical (DPPH(•)) scavenging capacity and total antioxidant capacity ferric ion reducing activity. Superoxide anion radical was produced using potassium superoxide/18-crown-6-ether dissolved in dimethylsulfoxide, and the Fenton-like reaction (Fe(II) + H2O2) was a generator of hydroxyl radicals. Chemiluminescence, spectrophotometry, electron paramagnetic resonance (EPR) and 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as the spin trap were the measurement techniques. The results showed that the majority of the chromone derivatives tested showed a strong scavenging effect towards free radicals, similar to the chemiluminescence reaction with superoxide anion radical with a high activity, inhibition of the DMPO-OOH radical EPR signal (24-58%), the DMPO-OH radical EPR signal (4-75%) and DPPH radical EPR signal (6-100%) at 1 mmol/L. Several of the examined compounds exhibited the high reduction potentials. The results obtained show that the new synthesized chromone derivatives may directly scavenger reactive oxygen species and thus may play a protective role against oxidative damage. Copyright © 2014 John Wiley & Sons, Ltd.

  20. First Principles Study of Al-Li Intermetallic Compounds

    Science.gov (United States)

    Yu, Hai-li; Duan, Xiao-hui; Ma, Yong-jun; Zeng, Min

    2012-12-01

    The structural properties, heats of formation, elastic properties, and electronic structures of four compositions of binary Al-Li intermetallics, Al3Li, AlLi, Al2Li3, and Al4Li9, are analyzed in detail by using density functional theory. The calculated formation heats indicate a strong chemical interaction between Al and Li for all the Al-Li intermetallics. In particular, in the Li-rich Al-Li compounds, the thermodynamic stability of intermetallics linearly decreases with increasing concentration of Li. According to the computational single crystal elastic constants, all the four Al-Li intermetallic compounds considered here are mechanically stable. The polycrystalline elastic modulus and Poisson's ratio have been deduced by using Voigt, Reuss, and Hill approximations, and the calculated ratios of bulk modulus to shear modulus indicate that the four compositions of binary Al-Li intermetallics are brittle materials. With the increase of Li concentration, the bulk modulus of Al-Li intermetallics decreases in a linear manner.

  1. Study on the Characteristic Organic Compounds in Red Tide by Factor Analysis Method

    Institute of Scientific and Technical Information of China (English)

    赵明桥; 李攻科; 张展霞

    2004-01-01

    Factor analysis is used to study the organic compounds that have high degree of correlation with biomass in algal blooming. Based on this correlation, they are named characteristic organic compounds. The compounds found are sequalene (SQU), cedrol (CED), 2, 5-cyclohexadiene-1, 4-dione, 2, 6-bis(1, 1-dimthylethyl )(PBQ), phenol, 2, 6-bis (1, 1-dimethylethy-4-methyl) (BHT), 3-t-butyl-4-hydroxyanisole ( BHA ), 1, 2-benzenedicarboxylie acid, bis-( 2-methyl propyl ) ester (DIBP), dibutyl phthalate (DNBP), respectively. Monitoring the variations of concentration of these characteristic organic compounds in seawater may provide scientific basis for studying and forecasting red tides.

  2. Study of indoor air pollution by carbonyl compounds

    Energy Technology Data Exchange (ETDEWEB)

    Grimaldi, F.; Botti, P.; Bouthiba, M.; Gouezo, F.; Viala, A. [Faculte de Medecine, 13 - Marseille (France)

    1996-01-01

    Carbonyl compounds reach indoor occasionally high air concentrations. They must be taken into attentive considerations, particularly because of their irritative and possibly carcinogenic effects. They were sampled in air through dinitro-2,4- phenylhydrazinc (DNPH)-Silica cartridges. The 2,4-dinitrophenylhydrazones formed were then eluted with acetonitrile and determined by high-performance liquid chromatography. The used method is selective and gives a linear reproducible and sensitive response. The obtained results (for formaldehyde, acetaldehyde, acetone, acrolein, crotonaldehyde, butyraldehyde, benzaldehyde, isovaleraldehyde, o-tolualdehyde) inside teaching and other premises showed that it is necessary to avoid the stopping up, to ensure an efficient ventilation and to eliminate, at less to restrict a possible release, by using appropriate building and coating material and furniture. (authors). 14 refs., 2 figs., 5 tabs.

  3. Studies on the mode of action of lathyrogenic compounds.

    Science.gov (United States)

    LEVENE, C I

    1962-08-01

    The lathyrogenic effect of INAH in the chick embryo may be measured by the increase in the extractibility of collagen from the bones with 1 M NaCl. Incubation of these bones in vitro with carbonyl compounds diminishes the amount of extractible collagen; with D-L-glyceraldehyde the reversal of the INAH effect is complete. This reversal effect is dependent on the time and temperature of incubation and on the quantity of D-L-glyceraldehyde, but is independent of the pH of the incubating medium, the optical form of the glyceraldehyde, or the metabolism of the cells; this suggests that it depends on a simple chemical combination. D-L-glyceraldehyde also reverses completely the extractibility of collagen from the bones of embryos rendered lathyrogenic with BAPN, semicarbazide, and hydrazine hydrate. The hypothesis has been advanced "that lathyrogenic agents act by blocking carbonyl groups on the collagen molecule, thus preventing cross-linking essential to normal maturation; normal maturation may be restored by the addition of carbonyl groups which act by competing either for the lathyrogen or for functional sites on the collagen molecule." In support of this hypothesis, it has been shown that purified lathyritic guinea pig collagen takes up lesser amounts of 2,4-dinitrophenylhydrazine-a compound which combines with carbonyl groups-than does normal collagen; it has been shown that lathyritic collagen still possesses the ability to form segment-long-spacing (SLS) collagen, but that these fibres are much thinner than normal; this is due perhaps to blockade of groups essential for lateral cross-linking of the tropocollagen unit. It has also been shown that normal, purified guinea pig collagen which has been pretreated with INAH, takes up lesser amounts of 2,4-dinitrophenylhydrazine and forms much thinner SLS fibres than the untreated controls.

  4. Studies on the stability of iodine compounds in iodized salt.

    Science.gov (United States)

    KELLY, F C

    1953-01-01

    Contributions made by five groups of investigators to the knowledge of the stability of different iodine compounds in salt, and of the extent of the losses of iodine which may occur when iodized salt is exposed to different conditions of storage and use, are discussed by the author.STABILITY OF THE IODINE COMPONENT IN IODIZED SALT IS DETERMINED BY: (1) moisture content of the salt and humidity of the atmosphere; (2) light, heat, and other meteorological factors; (3) impurities in the salt; (4) acidity or alkalinity of the mixture; and (5) the form in which iodine is present.When potassium iodide or sodium iodide is used as the iodizing agent, the iodide content of the salt will remain constant and its distribution will remain uniform for many months if the salt is packed dry in a container with an impervious lining and kept dry, preferably in a cool place and away from strong light. When these conditions cannot be met, it is desirable to iodize salt with potassium iodate. Under adverse conditions of moisture, heat, and sunlight, the iodine content of salt iodized with potassium iodate remains relatively constant.

  5. Use of Moessbauer spectroscopy to study reaction products of polyphenols and iron compounds

    Energy Technology Data Exchange (ETDEWEB)

    Gust, J. (Building Research Inst., Warsaw (Poland)); Suwalski, J. (Atomic Energy Inst., Otwock-Swierk (Poland))

    1994-05-01

    Moessbauer spectroscopy was used to study parameters of the reaction products of iron compounds (Fe[sup III]) and polyphenols with hydroxyl (OH) groups in ortho positions. Polyphenols used in the reaction were catechol, pyrogallol, gallic acid, and oak tannin. The Fe-containing compounds were hydrated ferric sulfate (Fe[sub 2][SO[sub 4

  6. [Study of water-soluble compounds from fungus garden of Odontotermes formosanus].

    Science.gov (United States)

    Xue, Dejun; Zhou, Hui; Zhang, Min; Xie, Kang; Zhang, Yong

    2005-10-01

    To study water-soluble compounds from fungus garden of Odontotermes formosanus. The chemical constituents of fungus garden were analyzed and identified by GC-MS. 28 compounds were separated and 11 chemical constituents were identified. The main constituents in water-solubles from fungus garden of Odontotermes formosanus are palmitic acid, linolei acid and oleic aid.

  7. Interaction of aromatic compounds with Photobacterium leiognathi luciferase: fluorescence anisotropy study

    NARCIS (Netherlands)

    Kudryasheva, N.S.; Nemtseva, E.V.; Visser, A.J.W.G.; Hoek, van A.

    2003-01-01

    The time-resolved and steady-state fluorescence techniques were employed to elucidate possible interactions of four aromatic compounds (anthracene, POPOP, MSB and 1,4-naphthalendiol) with bacterial luciferase. Fluorescence spectra and fluorescence anisotropy decays of these compounds were studied in

  8. Study on Compound Salvia Pellet in Treating Hypertensive Cerebral Hemorrhage

    Institute of Scientific and Technical Information of China (English)

    徐雄鹰; 陈霄峰

    2004-01-01

    Objective: To assess the efficacy and safety of compound Salvia pellet (CSP) in treating hypertensive cerebral hemorrhage (HCH). Methods: Control group (n= 116) was given HCH conventional therapy, and the treated group (n=118) given the same conventional therapy plus CSP 10 pills through sublingual sucking/6 hrs, the efficacy was compared. Results= (1) The 3rd day after admission CT monitoring showed both the volume of hematoma and hematoma plus edema in the treated group were smaller than those in the control group, the difference was significant (P<0.05); comparison between 14th day and 28th day after admission showed that the difference was significant (P<0.01). (2) The 14th day, 28th day and 3months after admission, regarding the Chinese stroke scale (CSS), activity of daily living (ADL) andmodified Barthol index (BI), the treated group was better than that of control group, the difference was significant (P<0.01). (3) The incidence of brain-heart syndrome reduced as time went by in both groups, but that of the treated group lowered more than that of control group, the difference being.significant (P<0.05, or P<0.01). Conclusion= CSP in treating HCH patients could cease the expansion of cerebral hematoma in the early phase, and accelerate the absorption of cerebral hematoma, improve the cerebral blood flow, alleviate cerebral edema, lower the disability, and elevate the quality of life. Besides, CSP also could prevent and treat brain-heart syndrome. CSP is cheap, convenient in administration, effective and safe.

  9. Study of local correlations of magnetic and multiferroic compounds

    CERN Multimedia

    Alves, E J

    We propose to study magnetic and multiferroic strongly correlated electron materials using radioactive nuclear probe techniques, at ISOLDE . Following the strategy of a previous project, IS390, our aim is to provide local and element selective information on some of the mechanisms that rule structural, charge and orbital correlations, electronic and magnetic interactions and the coupling of the associated degrees of freedom. The main technique used is Perturbed Angular Correlations (PAC), which allows combined magnetic and electric hyperfine studies. This study is complemented by the use of conventional characterisation techniques, and the investigation of relevant macroscopic properties.

  10. Compound headedness in the mental lexicon: an event-related potential study.

    Science.gov (United States)

    Arcara, Giorgio; Marelli, Marco; Buodo, Giulia; Mondini, Sara

    2014-01-01

    Compound words in Romance languages may have the head either in the initial or in the final position. In the present event-related potential (ERP) study, we address the hypothesis that Italian compounds are processed differently according to their head position and that this is mostly due to the perceived change in the canonical order of syntactic elements. Compound stimuli (head-initial, head-final, or exocentric) were visually displayed in two presentation modes, as whole words or separated into their constituents, in the context of a lexical decision task. Behavioural results showed an increased split cost in head-final and exocentric compounds as compared to head-initial compounds. ERP results showed an enhanced left anterior negativity (LAN) for head-final and exocentric compounds as compared to head-initial compounds, regardless of the presentation mode. Results suggest that the analogy with syntactic order may influence the internal structure of a compound and, as a consequence, its processing, but other characteristics (such as the grammatical properties of constituents) may affect the processing itself.

  11. Distinct morphological processing of recently learned compound words: An ERP study.

    Science.gov (United States)

    Kaczer, Laura; Timmer, Kalinka; Bavassi, Luz; Schiller, Niels O

    2015-12-10

    Our vocabulary is, at least in principle, infinite. We can create new words combining existing ones in meaningful ways to form new linguistic expressions. The present study investigated the morphological processing of novel compound words in overt speech production. Native speakers of Dutch learned a series of new compounds (e.g. appelgezicht, 'apple-face') that were later used as primes in a morphological priming task. In this protocol, primes were compound words morphologically related to a target's picture name (e.g. appelgezicht was used for a picture of an apple, Dutch appel). The novel primes were compared with corresponding familiar compounds sharing a free morpheme (e.g. appelmoes, 'applesauce') and with unrelated compounds. Participants were required to read aloud words and to name pictures in a long-lag design. Behavioral and event-related potentials (ERPs) data were collected in two sessions, separated by 48h. Clear facilitation of picture naming latencies was obtained when pictures were paired with morphological related words. Notably, our results show that novel compounds have a stronger priming effect than familiar compounds in both sessions, which is expressed in a marked reduction in target naming latencies and a decrease in the N400 amplitude. These results suggest that participants focused more on the separate constituents when reading novel primes than in the case of existing compounds.

  12. Synthesis, characterization, investigation of biological activity and theoretical studies of hydrazone compounds containing choloroacetyl group

    Science.gov (United States)

    Cukurovali, Alaaddin; Yilmaz, Engin

    2014-10-01

    In this study, three new hydrazide-hydrazone derivative compounds which contain choloroacetyl group have been synthesized and characterized. In the characterization, spectral techniques such as IR, 1H NMR, 13C NMR and UV-Vis spectroscopy techniques were used. Antibacterial effects of the synthesized compounds were investigated against Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853. In the theoretical calculations Gaussian 09 software was used with the DFT/6-311+(d,p) basis set. Experimental X-ray analysis of compounds has not been studied. Theoretical bond lengths of synthesized compounds were compared with experimental bond lengths of a similar compound. Theoretical and experimental bond lengths are in good agreement with R2: 0.896, 0.899 and 0.900 for compounds 1, 2, and 3, respectively. For antibacterial activity, the most effective one was found to be N‧-(4-bromobenzylidene)-2-chloro-N-(4-(3-methyl-3-phenylcyclobutyl)-thiazol-2-yl) acetohydrazide against P.aeroginaosa ATTC 27853, among the studied compounds.

  13. The Systematic Study of the Organotransition Metal Compounds.

    Science.gov (United States)

    Carriedo, Gabino A.

    1990-01-01

    Discussed is an extension of the conventional method for studying the organometallic chemistry of transition metals that may be useful to show how the various existing types of low-valence complexes can be constructed. This method allows students to design new types of complexes that may still be nonexistent. (CW)

  14. STUDY ON THE EVOLUTION OF MYOGLOBIN COMPOUNDS AFTER SLAUGHTER

    Directory of Open Access Journals (Sweden)

    Iuliana Manea

    2010-01-01

    Full Text Available The evolution of the molecular system involved in the color of the meat during the muscle rigor and agening wasanalyzed comparative in different kind of muscles from pork and beef meat collected from animals of different ages andspecies. This work hints to study the influence of some agents on pigments content in meat, during the muscle rigor andageing. Along this paper hinted to prove the importance of some parameters such as: the species, the age and the typeof muscle and the color of the meat. For study it has been used meat of two species (porcines and bovines and treetypes of muscle (trapez cervical, obliquus extern and longissimus dorsi. To highlight the influence of the age and thebreed of the animal on the color of its meat, the pigments concentration was calculated. It has been determined that thefull aged bovines’meat tissue has an increased content of pigments.

  15. STUDY ON THE EVOLUTION OF MYOGLOBIN COMPOUNDS AFTER SLAUGHTER

    OpenAIRE

    Iuliana Manea; Laur Constantin Manea

    2010-01-01

    The evolution of the molecular system involved in the color of the meat during the muscle rigor and agening wasanalyzed comparative in different kind of muscles from pork and beef meat collected from animals of different ages andspecies. This work hints to study the influence of some agents on pigments content in meat, during the muscle rigor andageing. Along this paper hinted to prove the importance of some parameters such as: the species, the age and the typeof muscle and the color of the m...

  16. Core-shell particles as model compound for studying fouling

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Nielsen, Troels Bach; Andersen, Morten Boel Overgaard;

    2008-01-01

    Synthetic colloidal particles with hard cores and soft, water-swollen shells were used to study cake formation during ultrafiltration. The total cake resistance was lowest for particles with thick shells, which indicates that interparticular forces between particles (steric hindrance...... and electrostatic repulsion) influenced cake formation. At low pressure the specific cake resistance could be predicted from the Kozeny-Carman equation. At higher pressures, the resistance increased due to cake compression. Both cake formation and compression were reversible. For particles with thick shells...... the permeate flux could be enhanced by lowering the pressure. Hence, the amount of water-swollen material influences both cake thickness and resistance....

  17. Study on electrochemical characteristics of steel in molten sodium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Aoto, Kazumi [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center

    2003-06-01

    Electrochemical characteristics of steel corrosion in molten sodium oxides were studied. No report exists about such electrochemical experiments in the melt because this molten salt is very corrosive and sodium easily corrodes gold used as a reference electrode by forming eutectics. In this study, proper protection using zirconia for the equipment part exposed to the corrosive atmosphere and the acceleration of scanning rate of the electric potential led to realization of the measurement of corrosion potential and polarization curves of steel in molten sodium oxides. Electrochemical characteristics measured agreed with the features of two types of corrosion derived from previous works such as the immersed corrosion test. Those are consistent with the fact that 'Molten salt type corrosion' occurs in the melt with higher oxygen potential and 'Na-Fe double oxidation type corrosion' occurs in the basic melt. The estimated corrosion rate for the corrosion based on the corrosion current density almost agrees with the prediction by each proposed equation. (author)

  18. Sediment Transport Study in Haeundae Beach using Radioisotope Labelled Compound

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Seop; Kim, Jong Bum; Jung, Sung Hee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Lee, Jong Sup [Pukyong National Univ., Busan (Korea, Republic of)

    2005-07-01

    Haeundae beach is one of the most famous resorts in Korea and plays an important role as a special tourism district. However, the length and width of the beach are being reduced continuously, which would have bad influence on the regional economy and be the financial burden to the local authority considering that a large amount of budget is spent in the beach nourishment annually. Hence, it is necessary to understand the dynamic behavior of sediments in the coast for the systematic preservation plan of coastal environment. Lately a monitoring system using radioactive isotope as tracers is considered as a novel technique in understanding the dynamic transport of sediments. The objective of this study is to investigate the possible variations in sedimentary distribution and quantify the characteristics of sediments using radiotracer.

  19. Comparative Study of Volatile Compounds from Genus Ocimum

    Directory of Open Access Journals (Sweden)

    S. R. Vani

    2009-01-01

    Full Text Available There are distinct varieties of basil types in the genus Ocimum which makes them very special. Genus Ocimum is widespread over Asia, Africa and Central & Southern America. All basils are member of the Lamiaceae family. The colors of the leaves vary from bright green to purple-green and sometimes almost black. Fresh basil leaves have a strong and characteristic aroma, not comparable to any other spice, although there is a hint of clove traceable. Ocimum Sanctum, also addressed as Ocimum Tenuiflorum is a sacred plant in the Hindu culture and known as Tulasi in Tamil or Holy Basil in English. Meanwhile Ocimum Basilicum, known as Common or Sweet Basil has very dark green leaves. The genus Ocimum is cultivated for its remarkable essential oil which exhibits many usages such as in medicinal application, herbs, culinary, perfume for herbal toiletries, aromatherapy treatment and as flavoring agent. Due to varying essential oil profiles even within the same species, plants may often be classified as a different species as a result of different scents. In the present study, volatile constituents of Ocimum Sanctum and Ocimum Basilicum were extracted using various solvents and their chemical constituents were identified and quantified by using GC-MS in optimized conditions. The profiles of extract from both species were compared in an effort to investigate effects of seasonal variation on their chemical compositions. The predominant species in Ocimum Sanctum and Ocimum Basilicum was found to be methyl eugenol and methyl chavicol, respectively, during different months of analysis.

  20. An in silico study on antidiabetic activity of bioactive compounds in Euphorbia thymifolia Linn.

    Science.gov (United States)

    Nguyen Vo, T Hoang; Tran, Ngan; Nguyen, Dat; Le, Ly

    2016-01-01

    Herbal medicines have become strongly preferred treatment to reduce the negative impacts of diabetes mellitus (DM) and its severe complications due to lesser side effects and low cost. Recently, strong anti-hyperglycemic effect of Euphorbia thymifolia Linn. (E. thymifolia) on mice models has reported but the action mechanism of its bioactive compounds has remained unknown. This study aimed to evaluate molecular interactions existing between various bioactive compounds in E. thymifolia and targeted proteins related to Type 2 DM. This process involved the molecular docking of 3D structures of those substances into 4 targeted proteins: 11-β hydroxysteroid dehydrogenase type 1, glutamine: fructose-6-phosphate amidotransferase, protein-tyrosine phosphatase 1B and mono-ADP-ribosyltransferase sirtuin-6. In the next step, LigandScout was applied to evaluate the bonds formed between 20 ligands and the binding sites of each targeted proteins. The results identified seven bioactive compounds with high binding affinity (bioactive compounds, in silico approach is performed.

  1. Relationship between electronic properties and drug activity of seven quinoxaline compounds: A DFT study

    Science.gov (United States)

    Behzadi, Hadi; Roonasi, Payman; Assle taghipour, Khatoon; van der Spoel, David; Manzetti, Sergio

    2015-07-01

    The quantum chemical calculations at the DFT/B3LYP level of theory were carried out on seven quinoxaline compounds, which have been synthesized as anti-Mycobacterium tuberculosis agents. Three conformers were optimized for each compound and the lowest energy structure was found and used in further calculations. The electronic properties including EHOMO, ELUMO and related parameters as well as electron density around oxygen and nitrogen atoms were calculated for each compound. The relationship between the calculated electronic parameters and biological activity of the studied compounds were investigated. Six similar quinoxaline derivatives with possible more drug activity were suggested based on the calculated electronic descriptors. A mechanism was proposed and discussed based on the calculated electronic parameters and bond dissociation energies.

  2. Study of compounds emitted during thermo-oxidative decomposition of polyester fabrics

    Directory of Open Access Journals (Sweden)

    Dzięcioł Małgorzata

    2016-03-01

    Full Text Available Compounds emitted during thermo-oxidative decomposition of three commercial polyester fabrics for indoor outfit and decorations (upholstery, curtains were studied. The experiments were carried out in a flow tubular furnace at 600°C in an air atmosphere. During decomposition process the complex mixtures of volatile and solid compounds were emitted. The main volatile products were carbon oxides, benzene, acetaldehyde, vinyl benzoate and acetophe-none. The emitted solid compounds consisted mainly of aromatic carboxylic acids and its derivatives, among which the greatest part took terephthalic acid, monovinyl terephthalate and benzoic acid. The small amounts of polycyclic aromatic hydrocarbons were also emitted. The emission profiles of the tested polyester fabrics were similar. The presence of toxic compounds indicates the possibility of serious hazard for people during fire.

  3. DOCKING STUDIES OF CURCUMIN AS A POTENTIAL LEAD COMPOUND TO DEVELOP NOVEL DIPEPTYDYL PEPTIDASE-4 INHIBITORS

    Directory of Open Access Journals (Sweden)

    Enade Perdana Istyastono

    2010-06-01

    Full Text Available Interaction of curcumin to dipeptydyl peptidase-4 (DPP-4 has been studied by employing docking method using Molecular Operating Environment (MOE and AutoDock as the docking software applications. Although MOE can sample more conformational spaces that represent the original interaction poses than AutoDock, both softwares serve as valid and acceptable docking applications to study the interactions of small compound to DPP-4. The calculated free energy of binding (DGbinding results from MOE and AutoDock shows that curcumin is needed to be optimized to reach similar or better DGbinding compare to the reference compound. Curcumin can be considered as a good lead compound in the development of new DPP-4 inhibitor. The results of these studies can serve as an initial effort of the further study.     Keywords: curcumin, docking, molecular operating environment (MOE, AutoDock, dipeptydyl peptidase-4 (DPP-4

  4. A structural and vibrational study of the chromyl chlorosulfate, fluorosulfate, and nitrate compounds

    CERN Document Server

    Brandán, Silvia A

    2014-01-01

    A Structural and Vibrational Study of the Chromyl Chlorosulfate, Fluorosulfate and Nitrate Compounds presents important studies related to the structural and vibrational properties on the chromyl compounds based on Ab-initio calculations. The synthesis and the study of such properties are of chemical importance because the stereo-chemistries and reactivities of these compounds are strongly dependent on the coordination modes that adopt the different ligands linked to the chromyl group. In this book, the geometries of all stable structures in gas phase for chromyl chlorosulfate, fluorosulfate, and nitrate are optimized by using Density functional Theory (DFT). Then, the complete assignments of all observed bands in the infrared and Raman spectra are performed combining DFT calculations with Pulay´s Scaled Quantum Mechanics Force Field (SQMFF) methodology and taking into account the type of coordination adopted by the chlorosulfate, fluorosulfate and nitrate ligands as monodentate and bidentate. Moreover, the ...

  5. Biomimetic studies of wood decay: Simulating the effect of low molecular weight compounds and fungal enzymes

    DEFF Research Database (Denmark)

    Hastrup, Anne Christine Steenkjær; Howell, Caitlin; Jellison, Jody

    The effect of FeCl3 (Fe3+), hydrogen peroxide (H2O2), a low molecular weight compound (2,3- Dihydroxybenzoic acid), and oxalic acid on wood were tested in a study designed to mimic wood degradation by brown rot fungi. Previous studies suggest that these components are involved in the early stages...

  6. Quantitative RHEED Studies of MBE Growth of 3-5 Compounds

    Science.gov (United States)

    1991-06-03

    4/30/91 4. TITLE AND SUBTITLE Quantitative RHEED Studies of MBE Growth of III-V Compounds 6. AUTHOR(S) Ben G. Streetman S. FUNDING NUMBERS...Sto e39- 𔄂 :«8 -:J 2-89) Quantitative RHEED Studies of MBE Growth of III-V Compounds Final Report June 3, 1991 U.S. Army Research Office...Most Important Results The thrust of the research has been to develop better control of MBE growth using enhanced RHEED measurements and to use the

  7. [Studies on the marker compounds for standardization of traditional Chinese medicine "polyporus sclerotium ([symbol: see text])"].

    Science.gov (United States)

    Yuan, Dan; Yamamoto, Kei-ichi; Bi, Kaishun; Zhang, Ping; Liu, Fang; Kano, Yoshihiro

    2003-02-01

    Natural products have been used for healthcare and pharmacotherapy. Because difficulties in quality control affect their production, processing, and marketing, it is necessary to establish adequate marker compounds for their effective application. Ergosta-4,6,8(14),22-tetraen-3-one(I) was studied in the screening of the marker compounds for the standardization of Polyporus Sclerotium ([symbol: see text]), which has the advantage of easy qualitative and quantitative analysis because of its fluorescence. Its applicability in the standardization of Polyporus Sclerotium is discussed based on comparative studies of 30 crude samples of Polyporus Sclerotium and some other fungi herbs using TLC and HPLC analysis with I it as the marker compound, as well as its chemical synthesis.

  8. Determination of some phenolic compounds in Crocus sativus L. corms and its antioxidant activities study

    Directory of Open Access Journals (Sweden)

    N Esmaeili

    2011-01-01

    Full Text Available It is well known that phenolic compounds are constituents of many plants. In this study, the total phenolics content in Crocus sativus L. corms in dormancy and waking stages were determined by the Folin-Ciocalteu method. Analysis was carried out by gas chromatography-mass spectrometry (GC-MS after silylation by N-methyl-N-trimethylsilyl trifluroacetamide (MSTFA + %1 trimethyl iodosilane (TMIS. Numerous compounds were detected and 11 compounds were identified. The highest phenolics content in waking corms was observed for gentisic acid (5.693 ± 0.057 μg/g and the lowest for gallic acid (0.416 ± 0.006 μg/g; also these two phenolic compounds are the highest (0.929 ± 0.015 μg/g and lowest (0.017 ± 0.001 μg/g phenolics in dormant corms, respectively. The results from quantization and GC-MS analysis showed a high concentration of phenolic compounds in waking corms than the dormant stage. Furthermore, the radical scavenging activities of saffron corms were studied by 1,1-diphenyl-2-pycrylhydrazyl (DPPH test and EC 50 values were determined about 2055 ppm and 8274 ppm for waking and dormant corms, respectively.

  9. Preparation, characterization and photoluminescent studies of Cr and Nd co-doped Ce:YAG compounds

    Energy Technology Data Exchange (ETDEWEB)

    Naik, S.R. [Department of Chemistry, Goa University, Goa 403206 (India); Shripathi, T. [UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore 452017 (India); Salker, A.V., E-mail: sal_arun@rediffmail.com [Department of Chemistry, Goa University, Goa 403206 (India)

    2015-05-15

    Sol–gel autocombustion as an efficient method in the preparation of monophasic Cr and Nd co-doped Ce:YAG compounds has been demonstrated. A reduction in the formation temperature to 1000 °C as compared to the classical ceramic method has been effectively shown. Monophasic formation of the compounds has been confirmed from the X-ray diffraction study which is equally supported by the Raman spectroscopy. The TEM analysis confirms the formation of submicron sized particles (around 100 nm) which are equally supported by SEM micrographs revealing the granular morphology for the compounds. Photoluminescence (excitation) studies carried out for the compounds at 468, 341 and 685 nm display excellent emission intensity for the compounds with similar emission pattern pointing towards a common emission centre in all the three cases. Decrease in Ce{sup 3+} emission intensity for the Cr and Nd co-doped Ce:YAG is observed. Energy transfer mechanism is suggested for the lowering of emission intensity confirming the activity of Ce{sup 3+} as a sensitizer. - Highlights: • Nd and Cr co-doped Ce:YAG are prepared by the sol–gel autocombustion. • Monophasic preparation proves the method to be efficient. • Formation of particles around 100 nm is confirmed from TEM. • Singly doped Ce:YAG exhibits maximum emission intensity. • Energy transfer between ions in excited state is in co-doped samples.

  10. Topological properties of phosphorene-like monolayer group V semiconductor compounds: a first-principles study

    CERN Document Server

    Yu, Weiyang; Niu, Chun-Yao; Li, Chong; Cho, Jun-Hyung; Jia, Yu

    2015-01-01

    To broaden the scope of layered group V semiconductors, we propose a class of phosphorenelike monolayer group V semiconductor compounds, such as PN, AsP, SbP and BiP with black-phosphorus-like alpha-phase and blue-phosphorus-like beta-phase, respectively. Using first-principles density functional theory calculations, we study yet unrealized structural phases of these compounds. We find the black-phosphorus-like alpha-phase to be almost equally stable as the blue-phosphorus-like beta-phase. alpha-phase compounds display a direct band gap, while beta-phase compounds display an indirect band gap. Both alpha-phase and beta-phase monolayers depends sensitively on the in-layer strain, as is studied with alpha- and beta- AsP and BiP. Further more, We find that alpha-BiP presents an intriguing topological state when gained a compress from -8% to -10%, offering an unprecedented tunability in structural and electronic properties of BiP compound.

  11. Recent progress of soft X-ray photoelectron spectroscopy studies of uranium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Fujimori, Shin-ichi; Takeda, Yukiharu; Okane, Tetsuo; Saitoh, Yuji [Condensed Matter Science Divisions, Japan Atomic Energy Agency, Sayo, Hyogo (Japan); Fujimori, Atsushi [Condensed Matter Science Divisions, Japan Atomic Energy Agency, Sayo, Hyogo (Japan); Department of Physics, University of Tokyo, Hongo, Tokyo 113-0033 (Japan); Yamagami, Hiroshi [Condensed Matter Science Divisions, Japan Atomic Energy Agency, Sayo, Hyogo (Japan); Department of Physics, Faculty of Science, Kyoto Sangyo University, Kyoto 603-8555 (Japan); Yamamoto, Etsuji; Haga, Yoshinori [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Ōnuki, Yoshichika [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Faculty of Science, University of the Ryukyus, Nishihara, Okinawa 903-0213 (Japan)

    2016-04-15

    Recent progresses in the soft X-ray photoelectron spectroscopy (PES) studies (hν ≳ 100 eV) for uranium compounds are briefly reviewed. The soft X-ray PES has enhanced sensitivities for the bulk U 5f electronic structure, which is essential to understand the unique physical properties of uranium compounds. In particular, the recent remarkable improvement in energy resolutions from an order of 1 eV to 100 meV made it possible to observe fine structures in U 5f density of states. Furthermore, soft X-ray ARPES becomes available due to the increase of photon flux at beamlines in third generation synchrotron radiation facilities.The technique made it possible to observe bulk band structures and Fermi surfaces of uranium compounds and therefore, the results can be directly compared with theoretical models such as band-structure calculations. The core-level spectra of uranium compounds show a systematic behavior depending on their electronic structures, suggesting that they can be utilized to determine basic physical parameters such as the U 5f-ligand hybridizations or Comlomb interaction between U 5f electrons. It is shown that soft X-ray PES provides unique opportunities to understand the electronic structures of uranium compounds.

  12. In vitro gastrointestinal digestion study of pomegranate juice phenolic compounds, anthocyanins, and vitamin C.

    Science.gov (United States)

    Pérez-Vicente, Antonio; Gil-Izquierdo, Angel; García-Viguera, Cristina

    2002-04-10

    Pomegranate is an important source of bioactive compounds, such as anthocyanins, other phenolic compounds, and ascorbic acid. In the present work an in vitro availability method has been used to assay the influence of the physiological conditions in the stomach and small intestine. This method enables the study of the release of anthocyanins, vitamin C, and total phenols from the pomegranate juice and their transformations during gastrointestinal digestion. Results have shown that pomegranate phenolic compounds are available during the digestion in a quite high amount (29%). Nevertheless, due to pH, anthocyanins are largely transformed into non-red forms and/or degraded (97%), and similar results are obtained for vitamin C (>95% degradation).

  13. A study of vehicles for dosing rodent whole embryo culture with non aqueous soluble compounds.

    Science.gov (United States)

    Augustine-Rauch, Karen A; Zhang, Qin; Kleinman, Mark; Lawton, Richard; Welsh, Michael J

    2004-05-01

    In rodent whole embryo culture (WEC), finding vehicles for non-aqueous-soluble compounds has been problematic due to developmental toxicity associated with many solvents. The purpose of this study was to identify alternative vehicles for insoluble compounds. In WEC, we evaluated carrier solutions containing bovine serum albumin (BSA) and glycerol as well as the solvents, formamide, dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and ethanol, for relative teratogenicity and delivery of the insoluble teratogen, all-trans retinoic acid (RA). At a concentration of glycerol carrier solutions were not teratogenic, although both inhibited robust formation of yolk sac vasculature. Both solutions delivered RA to the cultured rat embryos at higher doses. In summary, all four solvents/solutions may have utility as vehicles dependent upon the chemical properties of the compound to be solubilized.

  14. NMR studies of the conformation and motion of tetrahydrofuran in graphite intercalation compounds

    Energy Technology Data Exchange (ETDEWEB)

    Caplan, D. F. [Lawrence Berkeley Lab., CA (United States); California Univ., Berkeley, CA (United States). Dept. of Chemistry

    1991-11-01

    The behavior of tetrahydrofuran (THF) molecules intercalated in graphite layers in compounds Cs(THF){sub 1.3}C{sub 24} and K(THF){sub 2.5}C{sub 24} was studied by proton NMR. The graphite layers in these compounds impose a uniform ordering on the THF molecules, giving rise to sharp NMR spectra. Experimental and simulated proton NMR spectra were used to investigate geometry, orientation and conformation of intercalated THF, and to determine whether pseudorotation, a large amplitude low-frequency vibration observed in gaseous THF, can also occur in the constrained environment provided by the graphite intercalation compounds. Deuterium and multiple quantum proton NMR spectra were also simulated in order to determine if these techniques could further refine the proton NMR results.

  15. Theoretical studies on nonlinear optical properties of two newly synthesized compounds: EPVPC and OPVPC

    Institute of Scientific and Technical Information of China (English)

    孙元红; 赵珂; 王传奎; 罗毅; 延云兴; 陶绪堂; 蒋民华

    2005-01-01

    The nonlinear optical properties of two newly synthesized molecules 9-Ethyl-3-{2-[4-(2-Pyridin-4-yl-vinyl)-phenyl]-vinyl}-9H-carbazole (EPVPC) and 9-Octadecyl-3-{2-[4-(2-Pyridin-4-yl-vinyl)-phenyl]-vinyl}-9H-carbazole (OPVPC)have been studied with hybrid density functional theory (DFT/B3LYP). The generalized few-state model is employed to calculate the two-photon absorption cross sections of the compounds. The theoretical results are in good agreement with the available experimental measurements. It is found that the maximal two-photon absorption (TPA) cross sections of the compounds can be well described by a three-state model. The numerical simulation shows that both compounds have large two-photon absorption (TPA) cross sections and, furthermore, OPVPC displays a little stronger TPA activity than EPVPC in a lower frequency region.

  16. QSAR and SAR studies on the reduction of some aromatic nitro compounds by xanthine oxidase.

    Science.gov (United States)

    Thakur, Mamta; Thakur, Abhilash; Balasubramanian, Krishnan

    2006-01-01

    This work describes QSAR and SAR studies on the reduction of 27 aromatic nitro compounds by xanthine oxidase using both distance-based topological indices and quantum molecular descriptors along with indicator parameters. The application of a multiple linear regression analysis indicated that a combination of distance-based topological indices with the ad hoc molecular descriptors and the indicator parameters yielded a statistically significant model for the activity, log K (the reduction of aromatic nitro compounds by xanthine oxidase). The final selection of a potential aromatic nitro compound for the reduction by xanthine oxidase is made by quantum molecular modeling. We have found that, among the various parameters, the quantum Mulliken charge parameters on the fourth atom or para position relative to the nitro group correlated best with the activity.

  17. 2D-QSAR Studies on Pyrazole Compounds Containing Pyrimidine Amino

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The quantitative structure-activity relationship (QSAR) of 16 pyrazole compounds was studied by ab initio method at the HF/3-21G level using Guassian03 soft. The optimized structures together with some characteristic and electric parameters of the title compounds were obtained; some stereo-parameters were calculated by HyperChem software.Stepwise multiple regression method was adopted to establish bi- and tri-parametric models between biological activity and some parameters. The lager ΔE and logP, the higher biological activity; and the biological activity would be promoted with the smaller μ, QN and QPYRA. It provided a theory direction to synthesize some compounds with high activity.

  18. Clinical studies with oral lipid based formulations of poorly soluble compounds

    DEFF Research Database (Denmark)

    Fatouros, Dimitrios; Karpf, Ditte M; Nielsen, Flemming S

    2007-01-01

    of these properties on the in vivo performance of the formulation. Equally important is the effect of concurrent food intake on the bioavailability of poorly soluble compounds. The effect of food on the bioavailability of compounds formulated in lipid and surfactant based formulations is also reviewed.......This work is an attempt to give an overview of the clinical data available on lipid based formulations. Lipid and surfactant based formulations are recognized as a feasible approach to improve bioavailability of poorly soluble compounds. However not many clinical studies have been published so far....... Several drug products intended for oral administration have been marketed utilizing lipid and surfactant based formulations. Sandimmune((R)) and Sandimmune Neoral((R)) (cyclosporin A, Novartis), Norvir((R)) (ritonavir), and Fortovase((R)) (saquinavir) have been formulated in self-emulsifying drug delivery...

  19. Crystal Structure and Magnetic Studies of a New Nitronyl Nitroxide Compound

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Compound 1 was first synthesized and characterized. Its crystal structure and magnetic property were determined and investigated. Discussion about the molecule packing in crystal and the macroscopic magnetism was also presented, in combination with computing study of the spatial distribution over the molecule.

  20. Interactions of skin thickness and physicochemical properties of test compounds in percutaneous penetration studies

    NARCIS (Netherlands)

    Wilkinson, S.C.; Maas, W.J.M.; Nielsen, J.B.; Greaves, L.C.; Sandt, J.J.M. van de; Williams, F.M.

    2006-01-01

    Objectives: To determine the effect of skin thickness on the percutaneous penetration and distribution of test compounds with varying physicochemical properties using in vitro systems. Studies were carried out in accordance with OECD guidelines on skin absorption tests. Methods: Percutaneous penetra

  1. NMR and DFT Study of Co-C Bond Activation Mechanism in Vitamin B12 Compounds

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ This report focuses on a theoretical study of the cobalt-cabon bond activation mechanism in Vitamin B12, its coenzyme complexes, and model compounds such as cobalamins (Cbl), cobaloximes and cobalt porphyrins. In particular, emphasis is placed on the nucleotide loop and its role in the baseon and baseoff mechanism.

  2. Teaching Compound Words to a Spelling-Disabled Child via Smart Notebook Technology: ? Case Study Approach

    Science.gov (United States)

    Tsesmeli, Styliani N.; Tsirozi, Theologia

    2015-01-01

    The case-study aims to examine the effectiveness of training of morphological structure on the spelling of compounds by a spelling-disabled primary school student. The experimental design of the intervention was based on the word-pair paradigm and included a pre-test, a training program and a post-test (n = 50 pairs). The Training Program aimed to…

  3. Studies on Molecular Recongnition of (a)-Cyclodextrin with Diphenyl compounds

    Institute of Scientific and Technical Information of China (English)

    ZHANG You-ming; YAO Hong; WEI Tai-bao

    2004-01-01

    The cyclodextrins(CDs) are a class of cyclic oligosaccharides made up of six(a), seven(a)or more [a-(1,4)-linked] D-glucopyranose units, and shaped like truncated cones with primary and secondary hydroxyl groups crowning the narrower rim and wider rim respectively. As they have a hydrophobic cavity of appropriate dimension, they can bind with various guest moleculars, such as hydrocarbon, cyclohexane, aromatic compounds, to form inclusion complexes. The cyclodextins inclusion complexation has been considered an ideal model mimicking the enzyme-substrate interaction and a lot of effect has been devoted to it. In this paper, we report our investigation on the inclusion complexation behavior of a-cyclodextrin(a-CD) with diphenyl compounds in order to further explore the molecular recongnition mechanism of 2:1 inclusion complexation of a-CD with aromatic compounds.Figure 1: Possible structures of the inclusion compounds.The inclusion complexation behavior of a-CD with sym-diphenyl-urea, sym-diphenyl-thiourea and diphenyl kotone as respective guest moleclars was studied by ultraviolet spectrometric titrations.The absorption spectral changes observed for the compounds in the absence and presence of a-CD are used to draw the corresponding Benesi-Hildebrand plots and caculate the complex stability constant value (Ks) for the inclusion compounds.The 2:1 inclusion complexations show higher binding constants by cooperative binding of one guest molecular in the closely two hydrophobic cyclodextrin cavites as compared with 1:1 inclusion complexations.The highest value observed for sym-diphenyl-urea could be due to the formation of a hydrogen bond between the carbonyl group and the hydrogen in the hydroxyl group of CD and this is not possible with sym-tiphenyl-thiourea. The lowest value observed for diphenyl kotone indicate the hydrophobic interaction is one of the binding force of cyclodextrin inclusion complex.

  4. A new vibrational study of Acetazolamide compound based on normal coordinate analysis and DFT calculations

    Science.gov (United States)

    Brandán, S. A.; Eroğlu, E.; Ledesma, A. E.; Oltulu, O.; Yalçınkaya, O. B.

    2011-05-01

    We have studied the 5-acetamido-1,3,4-thiadiazole-2-sulphonamide compound and characterized it by infrared and Raman spectroscopy in the solid phase. The Density Functional Theory (DFT) method together with Pople's basis set show that two stable molecules for the compound have been theoretically determined in the gas phase, and that only the more stable conformation is present in the solid phase, as was experimentally observed. The harmonic vibrational wavenumbers for the optimized geometry were calculated at B3LYP/6-31G ∗ and B3LYP/6-311++G ∗∗ levels at the proximity of the isolated molecule. For a complete assignment of the vibrational spectra in the compound solid, DFT calculations were combined with Pulaýs Scaled Quantum Mechanics Force Field (SQMFF) methodology in order to fit the theoretical wavenumber values to the experimental ones. In this way, a complete assignment of all of the observed bands in the infrared spectrum for the compound was performed. The natural bond orbital (NBO) study reveals the characteristics of the electronic delocalization of the two structures, while the corresponding topological properties of electronic charge density are analysed by employing Bader's Atoms in the Molecules theory (AIM).

  5. In depth study of molybdenum silicon compound formation at buried interfaces

    Science.gov (United States)

    Zoethout, Erwin; Louis, Eric; Bijkerk, Fred

    2016-09-01

    Angle resolved x-ray photoelectron spectroscopy (ARXPS) has been employed to determine non-destructively the in-depth interface formation during thin film growth. Buried interfaces underneath the nanometer thick layers are probed by identifying the chemical shift of compound materials in photoelectron spectroscopy and using the angular response to quantify the compound amounts from the measured intensities. The thin interfaces in molybdenum-silicon multilayers grown at ambient temperature are investigated. This system is an example of an almost perfect 1D-system, where the interface region is only a small part of the individual layer thicknesses of 3 to 5 nm. Despite the low growth temperature, both the interfaces of this multilayer show layer thickness dependent interface formation. While the silicon-on-molybdenum interface shows a limited interface thickness of 0.4 nm of Mo5Si3, the molybdenum-on-silicon interface shows a more complex evolution. For this interface, the composition of the first 2.0 nm of deposited layer thickness is best described as a molybdenum-silicon compound layer with a molybdenum rich top and a MoSi2 bottom layer. After 2.5 nm of the deposited layer thickness, the molybdenum rich compound at the top has transformed into polycrystalline molybdenum on top of 1.8 nm MoSi2 at the interface. The formation of the 1.8 nm MoSi2 precedes the formation of polycrystalline molybdenum on top. Angle resolved x-ray photoelectron spectroscopy (ARXPS) is shown to be a good tool to study the interface phenomena beneath the nanometer thick top layers. In the case of Mo/Si multilayer mirrors, this ARXPS study shows that the compound formation at the interface accounts for the majority of the extreme ultraviolet reflectance loss.

  6. A study of suitability of some conventional chemical preservatives and natural antimicrobial compounds in allelopathic research

    Directory of Open Access Journals (Sweden)

    Plamen Marinov-Serafimov

    2015-12-01

    Full Text Available The impact of three conventional chemical preservatives (sodium benzoate, potassium sorbate and salicylic acid and a natural antimicrobial compound (thymol on germination, dynamics of growth and accumulation of fresh biomass (g per seedling of Lactuca sativa L., cultivar Great Lakes, was studied under laboratory conditions. The tested conventional chemical preservatives demonstrated strong inhibitory effects (GI 27.1-0.0% on germination and initial development of L. sativa, and they cannot be used in allelopathic studies in the laboratory. An addition of thymol at 0.5-1.0 ‰ concentration showed no inhibitory effect (GI varied 81.7-84.6% on germination and initial development of L. sativa. Thymol can therefore be used as a natural antimicrobial compound in allelopathic studies in the laboratory.

  7. A Comparative Study of Dihydroartemisinin Compounds in Treatment of Uncomplicated Falciparum Malaria in Kampong of Cambodia

    Institute of Scientific and Technical Information of China (English)

    SONG Jian-ping(宋建平); Duong Socheat; Suou Seila

    2003-01-01

    Objective: To compare the safety and efficacy of two compounds of dihydroartemisinin (DHA) Artekin and Artekin (T) in the treatment of uncomplicated falciparum malaria. Methods: The regimen of 8-tablet for 2 days of Artekin and Artekin (T) were applied to 100 patients with uncomplicated falciparum malaria, who were randomly divided into two groups. Each group contained 50 cases. The cure rate, the mean parasites clearance time, the mean fever clearance and side-effects were observed to assess the safety and efficacy of the compounds used. Results: The mean parasites clearance time was 31.7±9.0 hours in the Artekin group and 32.8±8.8 hours in Artekin (T) group respectively;the mean fever clearance time was 12.7±7.2 hours in Artekin group and 16.5±7.9 hours in Artekin (T) group; there were no recrudescence case in both groups within the 28 days of follow-up,the cure rates in Artekin group and Artekin (T) groups were 100%. It indicated that the tolerability of both compounds were very good, the side-effects such as nausea, abdominal pain were mild and self-limited. Conclusion: The study preliminarily indicated that the DHA and PQ compounds were of high efficacy, rapid acting and low toxicity. Artekin is very promising as a cheap, simple, effective treatment for multi-resistance malaria in Cambodia.

  8. The Evolution of River–Lake and Urban Compound Systems: A Case Study in Wuhan, China

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2015-12-01

    Full Text Available The process of urbanization takes up a lot of wetlands, profoundly changing the natural connection of surrounding river–lake systems, all the while causing serious damage to the environment of connected catchments. Urban systems and river–lake systems are not isolated and static, there is a relation between them which is constantly changing. Based on the idea of system research, the urban system is simplified into four subsystems: environment, infrastructure, social, and economic. These four components interact together, influencing the river–lake system to form a compound system. This paper aims to reflect the features and evolution laws of the compound system, by building a Collaborative Development Model to study the changing of the compound system in Wuhan, China over a 10-year period. The results show that by implementing the Donghu Lake Ecological River Network Engineering Project, the damaged river–lake system in Wuhan showed some improvement. However, in order to improve the sustainability of the compound system in Wuhan, the status of the river–lake system, social system and environment system, which are still comparatively substandard, should be constantly improved. The Collaborative Development Model could also be used in other cities and regions, to provide the basis for sustainable development.

  9. New guаnidin-containing compounds with biocidal active: synthesis and prospects of study

    Directory of Open Access Journals (Sweden)

    Nadejda Kyznecova

    2014-04-01

    Full Text Available Synthesized a new complex compound-ditsitratoborat guanidinium studied its composition, structure , physical and chemical properties using IR spectroscopy , thermal , X-ray diffraction and elemental analysis , conductivity , quantum-chemical modeling . Proven biocidal activity against Escherichia coli, Staphylo-coccus aureus, yeasts bioassay methods . On the basis of silicate (clay and the Trans-Baikal Territory materials synthesized coordination compound obtained organic-inorganic composites in various ways (using mechanical activation and ultrasonic vibrations , studied its properties. The present invention extends the range of antiseptic preparations , the resulting composite is promising a wide range of applications due to their sorption properties and biocidal activity : qualitative improvement of natural , domestic, wastewater , swimming pools, reservoirs , soil objects .

  10. Non-clinical toxicity studies on bioactive compounds within the framework of nutritional and health claims.

    Science.gov (United States)

    Gil, Ana Gloria; Arbillaga, Leire; López de Cerain, Adela

    2015-07-01

    The growing presence of products on the market with added value in terms of health makes essential their regulation and harmonization in critical aspects such as safety. The toxicology applied to the bioactive compounds should demonstrate the absence of toxic effects at doses advised for consumption, as well as evaluate the potential toxic effects in the assumption that the products are used in quantities superior to those recommended. The specific strategy should be defined case by case; therefore, prior to any toxicological development, it is essential to study all the information regarding the bioactive compounds (BACs) characterization, nutridynamics and nutrikinetics, that is available. In this guideline, a general strategy to be applied in the development of BACs is proposed. It includes a first in vitro phase to discard genotoxicity and endocrine effects and a second in vivo phase with different possibilities regarding the duration and the extension of the studies.

  11. THE COMPARISON OF BALANCE ABILITIES OF RECURVE, COMPOUND AND TRADITIONAL ARCHERY: A PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Deniz ŞİMŞEK

    2013-04-01

    Full Text Available Archery is described as a static sport requiring fine movement control, proper endurance and strength of the upper body and balance ability.The purpose of this study was to examine differences in balance abilities during Recurve, Compound and Traditional Turkish Archery. Fourteen archers (Group I: The Recurve Archery (RA: n=5, Group II: Compound Archery (CA: n=4, Group III: Traditional Archery (TA: n=5 participated voluntary in the study. An 9281EA BioKistler Force Plate system was used to obtain objective measurements in medio-lateral (Ay and anterio-posterior (Ax directions of the sway of COP during the trials.The RA group displayed a slower COP sway range when compared to the CA and TA groups. The findings of this research suggest that archer drawing weight may affect shooting performance, especially during the releasing phase due to a shift in body weight (COP.

  12. Compound nouns in spoken language production by speakers with aphasia compared to neurologically healthy speakers: an exploratory study.

    Science.gov (United States)

    Eiesland, Eli Anne; Lind, Marianne

    2012-03-01

    Compounds are words that are made up of at least two other words (lexemes), featuring lexical and syntactic characteristics and thus particularly interesting for the study of language processing. Most studies of compounds and language processing have been based on data from experimental single word production and comprehension tasks. To enhance the ecological validity of morphological processing research, data from other contexts, such as discourse production, need to be considered. This study investigates the production of nominal compounds in semi-spontaneous spoken texts by a group of speakers with fluent types of aphasia compared to a group of neurologically healthy speakers. The speakers with aphasia produce significantly fewer nominal compound types in their texts than the non-aphasic speakers, and the compounds they produce exhibit fewer different types of semantic relations than the compounds produced by the non-aphasic speakers. The results are discussed in relation to theories of language processing.

  13. Comparison of PIXE and SXRF for kinetic studies in cell pharmacology of platinum and gold compounds

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, F. (Faculte de Medecine de Creteil (France). Lab. de Biophysique Laboratoire d' Analyse par Activation Pierre-Sue - Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)); Chevallier, P. (Paris-6 Univ., 75 (France)); Tapiero, H. (Hopital Paul-Brousse, 94 - Villejuif (France)); Massiot, P.; Piccot, D. (Laboratoire d' Analyse par Activation Pierre-Sue - Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)); Galle, P. (Faculte de Medecine de Creteil (France). Lab. de Biophysique); Silvestro, L. (Turin Univ. (Italy). Facolta di Medicina); Arizti, P. (Universidad Pais Vasco, Leioa (Spain). Facultad de Medicina)

    1991-01-01

    The analytical conditions in PIXE and SXRF are studied in order to optimize the detection of platinum and gold compounds in the cell and in their subcellular fractions. Calibration curves, reproducibility and detection limits were obtained with both techniques and compared. The best detection limit was achieved with SXRF. Preliminary data on the cellular pharmacokinetics of cisplatinum and gold selective distribution in nuclei were obtained by the above techniques. (author).

  14. Carbon isotopic study of individual alcohol compounds in modern sediments from Nansha Islands sea area, China

    Institute of Scientific and Technical Information of China (English)

    段毅; 文启彬; 郑国东; 罗斌杰

    1997-01-01

    Carbon isotopic compositions of individual n-alkanols and sterols in modern sediments from the Nan-sha Islands sea area are measured after derivatization to trimethylsilyl ethers by the new isotopic analytical technique of GC/C/IRMS. The effects of the three added silyl carbon atoms in every alcohol molecule on these compound isotopic compositions and the characteristics of their carbon isotopic compositions are studied. Then their biological sources are discussed using their carbon isotopic compositions.

  15. Fundamental studies on dynamic wear behavior of SBR rubber compounds modified by SBR rubber powder

    OpenAIRE

    Euchler, Eric; Heinrich, Gert; Michael, Hannes; Gehde, Michael; Stocek, Radek; Kratina, Ondrej; Kipscholl, Reinhold; Bunzel, Jörg-Michael; Saal, Wolfgang

    2016-01-01

    The aim of this study is focused on the experimental investigation of dynamic wear behavior of carbon black filled rubber compounds comprising pristine styrene butadiene rubber (SBR) together with incorporated SBR ground rubber (rubber powder). We also analyzed and described quantitatively the service conditions of some dynamically loaded rubber products, which are liable to wear (e.g. conveyor belts, tires). Beside the well-known standard test method to characterize wear resistance at steady...

  16. Monte Carlo study for γ+N→π+N at a new compound target

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An inbuilt compound target composed of carbon and tungsten is designed,and optimized by realistic GEANT4 Monte Carlo simulation.Also,we do a Monte Carlo study for single-pion photoproduction at the target.The results are presented from the simulation of pion yield,angular distribution and spectrum (at θ1ab,θcm=41°).These efforts are important to the coming measurement of the differential cross section for γ+N→π+N.

  17. Monitoring system for the study of autotrophic biofilms in bioremediation of polyaromatic compounds

    Science.gov (United States)

    Alarie, Jean P.; Bruttig, A.; Miller, Gordon H.; Hill, Walter; Vo-Dinh, Tuan

    1999-02-01

    carcinogens in laboratory animal assays. The parent homocyclic species, which contain only carbon and hydrogen, are the familiar polyaromatic hydrocarbon (PAH) compounds. In addition to the PAH compounds, there are thousands of substituted compounds that could have various substituent groups, such as alkyl, amino, chloro, cyano, hydroxy, oxy, or thio groups. In this study we investigate anthracene and pyrene as PAH model systems. A portable fiberoptic instrument capable of real-time measurements has been developed for field screening these PAHs in surface water and natural algae systems. Our preliminary studies investigated the detection limits of anthracene and pyrene and the adsorption properties of two algae using fluorescence monitoring. An exposure study of the algae to 5 ppb anthracene was performed to investigate the ability of the algae to adsorb PAHs.

  18. Computational and experimental study of the interactions between ionic liquids and volatile organic compounds.

    Science.gov (United States)

    Gao, Tingting; Andino, Jean M; Alvarez-Idaboy, J Raul

    2010-09-07

    Computational chemistry calculations were performed to investigate the interactions of ionic liquids with different classes of volatile organic compounds (VOCs), including alcohols, aldehydes, ketones, alkanes, alkenes, alkynes and aromatic compounds. At least one VOC was studied to represent each class. Initially, 1-butyl-3-methylimindazolium chloride (abbreviated as C(4)mimCl) was used as the test ionic liquid compound. Calculated interaction lengths between atoms in the ionic liquid and the VOC tested as well as thermodynamic data suggest that C(4)mimCl preferentially interacts with alcohols as compared to other classes of volatile organic compounds. The interactions of methanol with different kinds of ionic liquids, specifically 1-butyl-3-methylimidazolium bromine (C(4)mimBr) and 1-butyl-3-methylimidazolium tetrafluoroborate (C(4)mimBF(4)) were also studied. In comparing C(4)mimCl, C(4)mimBr, and C(4)mimBF(4), the computational results suggest that C(4)mimCl is more likely to interact with methanol. Laboratory experiments were performed to provide further evidence for the interaction between C(4)mimCl and different classes of VOCs. Fourier transform infrared spectroscopy was used to probe the ionic liquid surface before and after exposure to the VOCs that were tested. New spectral features were detected after exposure of C(4)mimCl to various alcohols. The new features are characteristic of the alcohols tested. No new IR features were detected after exposure of the C(4)mimCl to the aldehyde, ketone, alkane, alkene, alkyne or aromatic compounds studied. In addition, after exposing the C(4)mimCl to a multi-component mixture of various classes of compounds (including an alcohol), the only new peaks that were detected were characteristic of the alcohol that was tested. These experimental results demonstrated that C(4)mimCl is selective to alcohols, even in complex mixtures. The findings in this work provide information for future gas-phase alcohol sensor design.

  19. Highly Oxidized Multifunctional Organic Compounds Observed in Tropospheric Particles: A Field and Laboratory Study.

    Science.gov (United States)

    Mutzel, Anke; Poulain, Laurent; Berndt, Torsten; Iinuma, Yoshiteru; Rodigast, Maria; Böge, Olaf; Richters, Stefanie; Spindler, Gerald; Sipilä, Mikko; Jokinen, Tuija; Kulmala, Markku; Herrmann, Hartmut

    2015-07-07

    Very recent studies have reported the existence of highly oxidized multifunctional organic compounds (HOMs) with O/C ratios greater than 0.7. Because of their low vapor pressure, these compounds are often referred as extremely low-volatile organic compounds (ELVOCs), and thus, they are able to contribute significantly to organic mass in tropospheric particles. While HOMs have been successfully detected in the gas phase, their fate after uptake into particles remains unclear to date. Hence, the present study was designed to detect HOMs and related oxidation products in the particle phase and, thus, to shed light on their fate after phase transfer. To this end, aerosol chamber investigations of α-pinene ozonolysis were conducted under near environmental precursor concentrations (2.4 ppb) in a continuous flow reactor. The chemical characterization shows three classes of particle constituents: (1) intact HOMs that contain a carbonyl group, (2) particle-phase decomposition products, and (3) highly oxidized organosulfates (suggested to be addressed as HOOS). Besides chamber studies, HOM formation was also investigated during a measurement campaign conducted in summer 2013 at the TROPOS research station Melpitz. During this field campaign, gas-phase HOM formation was found to be correlated with an increase in the oxidation state of the organic aerosol.

  20. Crystallographic, DFT and docking (cathepsin B) studies on an organotellurium(IV) compound

    Energy Technology Data Exchange (ETDEWEB)

    Caracelli, Ignez; Maganhi, Stella H. [Univ. Federal de Sao Carlos (Brazil). BioMat; Zukerman-Schpector, Julio; Sousa Madureira, Lucas [Univ. Federal de Sao Carlos (Brazil). Lab. de Cristalografia, Estereodinamica e Modelagem Molecular; Stefani, Helio A. [Sao Paulo Univ. (Brazil). Dept. de Farmacia; Guadagnin, Rafael C. [Univ. Federal de Sao Paulo, Diadema (Brazil). Inst. e Ciencias Mabientais, Quimicas e Farmaceuticas; Tiekink, Edward R.T. [Sunway Univ., Selangor Darul Ehsan (Malaysia). Centre for Crystalline Materials

    2016-08-01

    Some biologically active organotellurium compounds exhibit inhibitory potency against cathepsin B. In this study, an alkyl derivative, viz. [CH{sub 3}(CH{sub 2}){sub 2}C(I)=C(H)](nBu)TeI{sub 2}, 1, has been structurally characterised by X-ray crystallography and shown to be coordinated within a C{sub 2}I{sub 2} donor set. When the stereochemically active lone pair of electrons is taken into account, a distorted trigonal bipyramidal geometry results with the iodide atoms in axial positions. Both intra- and inter-molecular Te..I interactions are also noted. If all interactions are considered, the coordination geometry is based on a Ψ-pentagonal bipyramidal geometry. An unusual feature of the structure is the curving of the functionalised C{sub 5} chain. This feature has been explored by DFT methods and shown to arise as a result of close C-H..I interactions. A docking study (cathepsin B) was performed to understand the inhibition mechanism and to compare the new results with previous observations. Notably, 1 has the same pose exhibited by analogous biologically active compounds with aryl groups. Thus, the present study suggests that (alkyl){sub 2}TeX{sub 2} compounds should also be evaluated for biological activity.

  1. A study of volatile compounds in the breath of children with type 1 diabetes

    CERN Document Server

    Stevens, S; Wei, C; Greenwood, R; Hamilton-Shield, J; Costello, B de Lacy; Ratcliffe, N; Probert, C

    2013-01-01

    A pilot study of exhaled volatile compounds and their correlation with blood glucose levels in eight children with type 1 diabetes is reported. Five paired blood and breath samples were obtained from each child over a 6 hour period. The blood glucose concentration ranged from 41.4 to 435.6 mg/dL. Breath samples were collected in Tedlar bags and immediately evacuated through thermal desorption tubes packed with Carbopack B and C. The VOCs were later recovered by thermal desorption and analysed using gas chromatography mass spectrometry. The study identified 74 volatile compounds present in at least 10% of the patient samples. Of these 74 volatiles 36 were found in all patient samples tested. Further analysis of the 36 compounds found that none showed significant overall correlation with blood glucose levels. Isoprene showed a weak negative correlation with blood glucose levels. Acetone was found to have no correlation with blood glucose levels for the patients studied. Some patients showed significant individu...

  2. A study revealing the key aroma compounds of steamed bread made by Chinese traditional sourdough.

    Science.gov (United States)

    Zhang, Guo-Hua; Wu, Tao; Sadiq, Faizan A; Yang, Huan-Yi; Liu, Tong-Jie; Ruan, Hui; He, Guo-Qing

    Aroma of Chinese steamed bread (CSB) is one of the important parameters that determines the overall quality attributes and consumer acceptance. However, the aroma profile of CSB still remains poorly understood, mainly because of relying on only a single method for aroma extraction in previous studies. Therefore, the objective of this study was to determine the volatile aroma compounds of five different samples of CSB using three different aroma extraction methods, namely solid-phase microextraction (SPME), simultaneous distillation-extraction (SDE), and purge and trap (P&T). All samples showed a unique aroma profile, which could be attributed to their unique microbial consortia. (E)-2-Nonenal and (E,E)-2,4-decadienal were the most prevalent aromatic compounds revealed by SDE, which have not been reported previously, while ethanol and acetic acid proved to be the most dominant compounds by both SPME and P&T. Our approach of combining three different aroma extraction methods provided better insights into the aroma profile of CSB, which had remained largely unknown in previous studies.

  3. A study revealing the key aroma compounds of steamed bread made by Chinese traditional sourdough*

    Science.gov (United States)

    Zhang, Guo-hua; Wu, Tao; Sadiq, Faizan A.; Yang, Huan-yi; Liu, Tong-jie; Ruan, Hui; He, Guo-qing

    2016-01-01

    Aroma of Chinese steamed bread (CSB) is one of the important parameters that determines the overall quality attributes and consumer acceptance. However, the aroma profile of CSB still remains poorly understood, mainly because of relying on only a single method for aroma extraction in previous studies. Therefore, the objective of this study was to determine the volatile aroma compounds of five different samples of CSB using three different aroma extraction methods, namely solid-phase microextraction (SPME), simultaneous distillation–extraction (SDE), and purge and trap (P&T). All samples showed a unique aroma profile, which could be attributed to their unique microbial consortia. (E)-2-Nonenal and (E,E)-2,4-decadienal were the most prevalent aromatic compounds revealed by SDE, which have not been reported previously, while ethanol and acetic acid proved to be the most dominant compounds by both SPME and P&T. Our approach of combining three different aroma extraction methods provided better insights into the aroma profile of CSB, which had remained largely unknown in previous studies. PMID:27704748

  4. Hydraphiles: A Rigorously Studied Class of Synthetic Channel Compounds with In Vivo Activity

    Directory of Open Access Journals (Sweden)

    Saeedeh Negin

    2013-01-01

    Full Text Available Hydraphiles are a class of synthetic ion channels that now have a twenty-year history of analysis and success. In early studies, these compounds were rigorously validated in a wide range of in vitro assays including liposomal ion flow detected by NMR or ion-selective electrodes, as well as biophysical experiments in planar bilayers. During the past decade, biological activity was observed for these compounds including toxicity to bacteria, yeast, and mammalian cells due to stress caused by the disruption of ion homeostasis. The channel mechanism was verified in cells using membrane polarity sensitive dyes, as well as patch clamping studies. This body of work has provided a solid foundation with which hydraphiles have recently demonstrated acute biological toxicity in the muscle tissue of living mice, as measured by whole animal fluorescence imaging and histological studies. Here we review the critical structure-activity relationships in the hydraphile family of compounds and the in vitro and in cellulo experiments that have validated their channel behavior. This report culminates with a description of recently reported efforts in which these molecules have demonstrated activity in living mice.

  5. A study on atomic diffusion behaviours in an Al-Mg compound casting process

    Science.gov (United States)

    Liu, Yongning; Chen, Yiqing; Yang, Chunhui

    2015-08-01

    Al and Mg alloys are main lightweight alloys of research interest and they both have superb material properties, i.e., low density and high specific strength, etc. Being different from Al alloys, the corrosion of Mg alloys is much more difficult to control. Therefore to combine merits of these two lightweight alloys as a composite-like structure is an ideal solution through using Al alloys as a protective layer for Mg alloys. Compound casting is a realistic technique to manufacture such a bi-metal structure. In this study, a compound casting technique is employed to fabricate bi-layered samples using Al and Mg and then the samples are analysed using electron probe micro-analyzer (EPMA) to determine diffusion behaviours between Al and Mg. The diffusion mechanism and behaviours between Al and Mg are studied numerically at atomic scale using molecular dynamics (MD) and parametric studies are conducted to find out influences of ambient temperature and pressure on the diffusion behaviours between Al and Mg. The results obtained clearly show the effectiveness of the compound casting process to increase the diffusion between Al and Mg and thus create the Al-base protection layer for Mg.

  6. Phytochemical study of phenolic compounds of labrador tea (Lédum palústre L.

    Directory of Open Access Journals (Sweden)

    Валентина Петровна Гапоненко

    2015-11-01

    Full Text Available Aim. This work is devoted a phytochemical study of biologically active substances in herb of Labrador Tea (Lédum palústre L., as well as investigation of the possibility of complex use of raw materials in order to create on its basis new herbal medicines.Methods. The object of the study served as the herb Labrador Tea. Separation of isolated substances was performed by adsorption and partition chromatography on various adsorbents. The structure of the isolated compounds was determined based on physicochemical methods: paper (PC and the thin layer (TLC chromatography, UV, IR and NMR spectroscopy in comparison with the original valid standards of flavonoids. Acid hydrolys was used for the determination of the flavonoid aglycone composition. The content of total flavonoids was determined by differential spectrophotometry at a wavelength of 412 nm from the reaction with aluminum chloride based on the hyperoside-standard (Ukrainian scientific Pharmacopoeial center for quality of medicines (Pharmacopoeial center, Kharkоv.Results. During this study we found more than 40 of phenolic compounds and identified 31compounds. The phytochemical analysis showed the presence of flavonols (11 compounds, catechins (5. Hydroxycinnamic acids represented by caffeic, ferulic, chlorogenic acids. Besides that, it were found phenolic glycoside arbutin, coumarins - coumarin, umbelliferon, scopoletin, esculetin and esculin, tannins – metyl gallate, pyrogallol.Conclusions. The following biologically active substances were defined for the first time: flavonoids – 5-methyl-kaempferol, avicularin, polistahozid, quercitrin; coumarins – esculetin, esculin; as well as hydroxycinnamic acids – ferulic, chlorogenic, neochlorogenic of Labrador Tea. The obtained data justify the prospectivefor creation of new and effective herbal medicines from Labrador Tea

  7. Normal coordinate analysis and fungicidal activity study on anilazine and its related compound using spectroscopic techniques

    Science.gov (United States)

    Sheeja Mol, Gilbert Pushpam; Arul Dhas, Deva Dhas; Hubert Joe, Isaac; Balachandran, Sreedharan

    2016-06-01

    The FTIR and FT-Raman spectra of anilazine have been recorded in the range 400-4000 cm-1 and 50-3500 cm-1 respectively. The optimized geometrical parameters of the compound were calculated using B3LYP method with 6-311G(d,p) basis set. The distribution of the vibrational bands were carried out with the help of normal coordinate analysis (NCA). The 1H and 13C nuclear spectra have been recorded and chemical shifts of the molecule were also calculated using the gauge independent atomic orbital (GIAO) method. The UV-Visible spectrum of the compound was recorded in the region 190-900 nm and the electronic properties were determined by time-dependent DFT (TD-DFT) approach. Anilazine was screened for its antifungal activity. Molecular docking studies are conducted to predict its fungicidal activity.

  8. QSAR study on estrogenic activity of structurally diverse compounds using generalized regression neural network

    Institute of Scientific and Technical Information of China (English)

    JI Li; WANG XiaoDong; LUO Si; QIN Liang; YANG XvShu; LIU ShuShen; WANG LianSheng

    2008-01-01

    Computer-based quantitative structure-activity relationship (QSAR) model has been becoming a powerful tool in understanding the structural requirements for chemicals to bind the estrogen receptor (ER), designing drugs for human estrogen replacement therapy, and identifying potential estrogenic endocrine disruptors, in this study, a simple yet powerful neural network technique, generalized regression neural network (GRNN) was used to develop a QSAR model based on 131 structurally diverse estrogens (training set). Only nine descriptors calculated solely from the molecular structures of compounds selected by objective and subjective feature selections were used as inputs of the GRNN model. The predictive power of the built model was found to be comparable to that of the more traditional techniques but requiring significantly easy implementation and a shorter computation-time. The obtained result indicates that the proposed GRNN model is robust and satisfactory, and can provide a feasible and practical tool for the rapid screening of the estrogenic activity of organic compounds.

  9. Comparative study of laterite and bentonite based organoclays: implications of hydrophobic compounds remediation from aqueous solutions.

    Science.gov (United States)

    Nafees, Muhammad; Waseem, Amir; Khan, Abdur Rehman

    2013-01-01

    Four cost effective organoclays were synthesized, characterized, and studied for the sorption of hydrophobic compounds (edible oil/grease and hydrocarbon oil) from aqueous solutions. Organoclays were prepared by cation exchange reaction of lattice ions (present onto the surface of laterite and bentonite clay minerals) with two surfactants, hexadecyl trimethyl ammonium chloride (HDTMA-Cl) and tetradecyl trimethyl ammonium bromide (TDTMA-Br). Fourier transform infrared spectroscopy and scanning electron microscopy were used for the characterization of synthesized organoclays. It was found that the amount of surfactant loading and the nature of the surfactant molecules used in the syntheses of organoclay strongly affect the sorption capacity of the clay mineral. Further, it was found that both the laterite and bentonite based organoclays efficiently removed the edible and hydrocarbon oil content from lab prepared emulsions; however, the adsorption capacity of clay mineral was greatly influenced by the nature of hydrophobic compounds as well.

  10. Chemometric studies of chemical compounds in five cultivars of potatoes from Tenerife.

    Science.gov (United States)

    Casañas, Ricardo; González, Mónica; Rodríguez, Elena; Marrero, Antonio; Díaz, Carlos

    2002-03-27

    A statistical study of correlation and multivariate analysis on the chemical composition of five cultivars of potatoes harvested in Tenerife was carried out to establish the relationships between the chemical compounds and, therefore, to differentiate the samples according to traditional and recent importation potatoes, cultivars, and species/subspecies. A large number of significant correlations between the chemical compounds were found, which suggests biochemical relationships among them. After factor analysis, the dimension space was reduced from 24 variables to eight factors, accounting for 77.2% of the total variance. Starch, moisture, organic acids, and metals are the variables that make it possible to characterize the system without losing very much information. Total differentiation of potato samples according to the criteria species/subspecies and cultivars was obtained using discriminant analysis with all the variables. However, with only four variables (weight of tuber, starch, amylose, and glucose + fructose) it is possible to differentiate between the traditional and recent importation potatoes.

  11. Comparative Study of Laterite and Bentonite Based Organoclays: Implications of Hydrophobic Compounds Remediation from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Muhammad Nafees

    2013-01-01

    Full Text Available Four cost effective organoclays were synthesized, characterized, and studied for the sorption of hydrophobic compounds (edible oil/grease and hydrocarbon oil from aqueous solutions. Organoclays were prepared by cation exchange reaction of lattice ions (present onto the surface of laterite and bentonite clay minerals with two surfactants, hexadecyl trimethyl ammonium chloride (HDTMA-Cl and tetradecyl trimethyl ammonium bromide (TDTMA-Br. Fourier transform infrared spectroscopy and scanning electron microscopy were used for the characterization of synthesized organoclays. It was found that the amount of surfactant loading and the nature of the surfactant molecules used in the syntheses of organoclay strongly affect the sorption capacity of the clay mineral. Further, it was found that both the laterite and bentonite based organoclays efficiently removed the edible and hydrocarbon oil content from lab prepared emulsions; however, the adsorption capacity of clay mineral was greatly influenced by the nature of hydrophobic compounds as well.

  12. Study of Reaction of Curium Oxy-Compound Formation in Molten Chlorides

    Energy Technology Data Exchange (ETDEWEB)

    Osipenko, A.G.; Mayorshin, A.A.; Bychkov, A.V. [Dimitrovgrad-10, Ulyanovsk region, 433510 (Russian Federation)

    2008-07-01

    The method of potentiometric titration using oxygen sensors with solid electrolyte membrane was applied for the study of the interaction of curium cations with oxygen anions in the molten alkali metal chlorides in the temperature range of 450-850 C degrees depending on oxy-acidity of the environment. Assumptions were made concerning ion and phase composition of the obtained high-temperature compounds and chemical reactions taking place in the melts. This scheme assumes that as the basicity of the melt increases, initially the formation of soluble curium oxychlorides takes place in the melt (presumably CmO{sup -}) that is followed by formation of solid CmOCl and finally sesquioxide Cm{sub 2}O{sub 3}. Basic thermodynamic values were calculated for the resultant curium oxy-compounds.

  13. Chemical kinetic study of the oxidation of toluene and related cyclic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Mehl, M; Frassoldati, A; Fietzek, R; Faravelli, T; Pitz, W; Ranzi, E

    2009-10-01

    Chemical kinetic models of hydrocarbons found in transportation fuels are needed to simulate combustion in engines and to improve engine performance. The study of the combustion of practical fuels, however, has to deal with their complex compositions, which generally involve hundreds of compounds. To provide a simplified approach for practical fuels, surrogate fuels including few relevant components are used instead of including all components. Among those components, toluene, the simplest of the alkyl benzenes, is one of the most prevalent aromatic compounds in gasoline in the U.S. (up to 30%) and is a promising candidate for formulating gasoline surrogates. Unfortunately, even though the combustion of aromatics been studied for a long time, the oxidation processes relevant to this class of compounds are still matter of discussion. In this work, the combustion of toluene is systematically approached through the analysis of the kinetics of some important intermediates contained in its kinetic submechanism. After discussing the combustion chemistry of cyclopentadiene, benzene, phenol and, finally, of toluene, the model is validated against literature experimental data over a wide range of operating conditions.

  14. Model compounds of humic acid and oxovanadium cations. Potentiometric titration and EPR spectroscopy studies

    Directory of Open Access Journals (Sweden)

    Mercê Ana Lucia Ramalho

    1999-01-01

    Full Text Available The stability constants and the isotropic EPR parameters Ao (hyperfine splitting constant and g o (g value were obtained by potentiometric titrations and EPR spectroscopy, respectively, of 85%v/v aqueous solutions of model compounds of humic acids - salicylic acid (SALA - and both nitrohumic acids, a laboratory artifact - nitrosalicylic acids, 3-nitrosalicylic acid (3-NSA, 5-nitrosalicylic acid (5-NSA and 3,5-dinitrosalicylic acid (3,5-DNSA and oxovanadium cations. It was possible to record EPR spectra of those model compounds and the ion VO2+ (V(IV, and the stability constants were obtained from a solution of VO3+ (V(V, the values for the logarithms of the stability constants ranging from 12.77 ± 0.04 to 7.06 ± 0.05 for the species ML, and from 9.90 ±0.04 to 4.06 ± 0.05 for the species ML2 according to the decrease in the acidity of the carboxylic and the hydroxyl groups in the aromatic ring of the model compounds studied as the -NO2 substituents were added. Species distribution diagrams were also obtained for the equilibria studied. The EPR parameters showed that as the logarithm of the overall stability constants increase, g o values also increase, while Ao values show a tendency to decrease.

  15. Dioxin-like compounds and endometriosis: a study on Italian and Belgian women of reproductive age.

    Science.gov (United States)

    De Felip, Elena; Porpora, Maria Grazia; di Domenico, Alessandro; Ingelido, Anna Maria; Cardelli, Massimo; Cosmi, Ermelando V; Donnez, Jacques

    2004-04-21

    Compounds with dioxin-like toxicity are suspected to adversely affect human reproduction even at current background exposures. Endometriosis, a gynecological disorder often associated with infertility, has been hypothesized to be linked to dioxins and similar chemicals, a hypothesis supported by the outcome of experimental studies on animal models. Endometriosis severity and incidence in Belgium is one of the highest of the world: in this country, the general population exposure to dioxin-like compounds has been, on average, higher than in most industrialized countries. Here we show the results of a pilot case-control study carried out on 22 Italian and 18 Belgian women of reproductive age, with and without endometriosis. No significant differences were found in dioxin-like compound body burdens between cases and controls on a country basis, whereas the body burdens of the Italian women resulted to be significantly lower than that of the Belgian. In particular, total TEQs in Italian and Belgian women without endometriosis were respectively 18 and 45 pg WHO-TE/g lb.

  16. Comparative Ab-Initio Study of Substituted Norbornadiene-Quadricyclane Compounds for Solar Thermal Storage.

    Science.gov (United States)

    Kuisma, Mikael J; Lundin, Angelica M; Moth-Poulsen, Kasper; Hyldgaard, Per; Erhart, Paul

    2016-02-25

    Molecular photoswitches that are capable of storing solar energy, so-called molecular solar thermal storage systems, are interesting candidates for future renewable energy applications. In this context, substituted norbornadiene-quadricyclane systems have received renewed interest due to recent advances in their synthesis. The optical, thermodynamic, and kinetic properties of these systems can vary dramatically depending on the chosen substituents. The molecular design of optimal compounds therefore requires a detailed understanding of the effect of individual substituents as well as their interplay. Here, we model absorption spectra, potential energy storage, and thermal barriers for back-conversion of several substituted systems using both single-reference (density functional theory using PBE, B3LYP, CAM-B3LYP, M06, M06-2x, and M06-L functionals as well as MP2 calculations) and multireference methods (complete active space techniques). Already the diaryl substituted compound displays a strong red-shift compared to the unsubstituted system, which is shown to result from the extension of the conjugated π-system upon substitution. Using specific donor/acceptor groups gives rise to a further albeit relatively smaller red-shift. The calculated storage energy is found to be rather insensitive to the specific substituents, although solvent effects are likely to be important and require further study. The barrier for thermal back-conversion exhibits strong multireference character and as a result is noticeably correlated with the red-shift. Two possible reaction paths for the thermal back-conversion of diaryl substituted quadricyclane are identified and it is shown that among the compounds considered the path via the acceptor side is systematically favored. Finally, the present study establishes the basis for high-throughput screening of norbornadiene-quadricyclane compounds as it provides guidelines for the level of accuracy that can be expected for key properties from

  17. Studies on Synthesis and Biological Activities of Novel Triazole Compounds Containing 1,3-Dioxolane

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Nine title compounds were synthesized. Their strucures were identified by means of IR, EA, 1H NMR and MS. The results from the primary biological test show that all the compounds have some activitiies of fungicide and plant growth regulator. When R group is 2,4-Cl2C6H3, compound 2 or compound 4 shows better biological activities.

  18. Pharmaceutical compounds in shallow groundwater in non-agricultural areas of Minnesota: study design, methods, and data, 2013

    Science.gov (United States)

    Elliott, Sarah M.; Erickson, Melinda L.

    2014-01-01

    The U.S. Geological Survey, in cooperation with the Minnesota Pollution Control Agency, completed a study on the occurrence of pharmaceutical compounds and other contaminants of emerging concern in shallow groundwater in non-agricultural areas of Minnesota during 2013. This report describes the study design and methods for the study on the occurrence of pharmaceuticals and other contaminants of emerging concern, and presents the data collected on pharmaceutical compounds. Samples were analyzed by the U.S. Geological Survey National Water Quality Laboratory for 110 pharmaceutical compounds using research method 9017. Samples from 21 of 45 wells had detectable concentrations of at least one of the 110 compounds analyzed. One sample contained detectable concentrations of nine compounds, which was the most detected in a single sample. Fewer than five compounds were detected in most samples. Among all samples, 27 of the 110 compounds were detected in groundwater from at least one well. Desmethyldiltiazem and nicotine were the most frequently detected compounds, each detected in 5 of 46 environmental samples (one well was sampled twice so a total of 46 environmental samples were collected from 45 wells). Caffeine had the highest detectable concentration of all the compounds at 2,060 nanograms per liter.

  19. Determinants of serum concentrations of organochlorine compounds in Swedish pregnant women: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Cnattingius Sven

    2007-02-01

    Full Text Available Abstract Background We performed a cross-sectional study of associations between personal characteristics and lipid-adjusted serum concentrations of certain PCB congeners and chlorinated pesticides/metabolites among 323 pregnant primiparous women from Uppsala County (age 18–41 years sampled 1996–1999. Methods Extensive personal interviews and questionnaires about personal characteristics were performed both during and after pregnancy. Concentrations of organochlorine compounds in serum lipids in late pregnancy were analysed by gas chromatography. Associations between personal characteristics and serum levels of organochlorine compounds were analysed by multiple linear regression. Results Participation rate was 82% (325 of 395 women. Serum concentrations of PCB congeners IUPAC no. 28, 52, 101, 105 and 167, and o, p'-DDT and -DDE, p, p'-DDT and -DDD, oxychlordane, and γ- and α-HCH were in many cases below the limit of quantification (LOQ. No statistical analysis of associations with personal characteristics could be performed for these substances. Concentrations of PCB congeners IUPAC no. 118, 138, 153, 156 and 180, HCB, β-HCH, trans-nonachlor and p, p'-DDE increased with increased age and were highest in women sampled early during the 4 year study period. This shows that older women and women sampled early in the study had experienced the highest life-time exposure levels, probably mainly during childhood and adolescence. The importance of early exposures was supported by lower PCB concentrations and higher β-HCH and p, p'-DDE concentrations among women born in non-Nordic countries. Moreover, serum concentrations of certain PCBs and pesticide/metabolites were positively associated with consumption of fatty fish during adolescence, and concentrations of CB 156, CB 180 and p, p'-DDE increased significantly with number of months women had been breast-fed during infancy. Short-term changes in bodily constitution may, however, also influence

  20. Crystal structure of ABPO5 and optical study of Pr3+ embedded in these compounds

    Science.gov (United States)

    Ben Ali, A.; Antic-Fidancev, E.; Viana, B.; Aschehoug, P.; Taibi, M.; Aride, J.; Boukhari, A.

    2001-10-01

    The crystal structure of borophosphates ABPO5 (A = alkaline earth or Pb) was resolved on a polycrystalline sample using the Rietveld method. The x-ray diffraction patterns data show that ABPO5 crystallize in a centrosymmetric space group P3121 and their structure is related to the borogermanates REBGeO5 with a stillwellite-type structure. Pr3+ ion was used as a local structural probe to corroborate the structural resolution results. Absorption and fluorescence spectra of A1-xPrxBP1-xGexO5 (A = alkaline earth or Pb; x = 0.05) have been investigated at different temperatures. At 9 K the 3H4 → 3P0 transition of trivalent praseodymium ion (4f2 configuration) is observed as a single line. This indicates a unique crystallographic site for the rare earth ion in these compounds replacing the divalent cation. Energy level schemes were deduced from the low-temperature spectroscopic measurements. Comparing the electronic level splittings of studied compounds with the already reported data on REBGeO5 doped with Pr3+ ion, it is possible to dispel the doubt existing about structural determination. Moreover, under 460 nm excitation, intense red emission of trivalent praseodymium is observed corresponding to 1D2 → 3H4 transition. The lifetime measurements of 1D2 level have been performed for all the title compounds.

  1. Experimental and computational studies of film cooling with compound angle injection

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, R.J.; Eckert, E.R.G.; Patankar, S.V.; Simon, T.W. [Univ. of Minnesota, Minneapolis, MN (United States). Dept. of Mechanical Engineering

    1995-12-31

    The thermal efficiency of gas turbine systems depends largely on the turbine inlet temperature. Recent decades have seen a steady rise in the inlet temperature and a resulting reduction in fuel consumption. At the same time, it has been necessary to employ intensive cooling of the hot components. Among various cooling methods, film cooling has become a standard method for cooling of the turbine airfoils and combustion chamber walls. The University of Minnesota program is a combined experimental and computational study of various film-cooling configurations. Whereas a large number of parameters influence film cooling processes, this research focuses on compound angle injection through a single row and through two rows of holes. Later work will investigate the values of contoured hole designs. An appreciation of the advantages of compound angle injection has risen recently with the demand for more effective cooling and with improved understanding of the flow; this project should continue to further this understanding. Approaches being applied include: (1) a new measurement system that extends the mass/heat transfer analogy to obtain both local film cooling and local mass (heat) transfer results in a single system, (2) direct measurement of three-dimensional turbulent transport in a highly-disturbed flow, (3) the use of compound angle and shaped holes to optimize film cooling performance, and (4) an exploration of anisotropy corrections to turbulence modeling of film cooling jets.

  2. A soft X-ray study of a Li-S surface compound

    Energy Technology Data Exchange (ETDEWEB)

    Shek, M.L. (Shek (M.L.), Ridge, NY (United States)); Sham, T.K. (Univ. of Western Ontario, London, Ontario (Canada). Dept. of Chemistry); Hrbek, J.; Xu, G.Q. (Brookhaven National Lab., Upton, NY (United States). Chemistry Dept.)

    1991-01-01

    The authors have studied a Li[sub 2]S[sub x] compound (x [approx] 0.79 to 0.95) with soft X-ray excited valence and core-level photoemission and Auger electron emission. The Li 1s core level is found at a binding energy of 56.9 eV, shifted by [approximately] 1.9 eV relative to the bulk 1s level of Li metal. The LiKVV Auger transition gives two peaks at kinetic energies 44.9 and 41.2 eV with respect to the Fermi level, corresponding to final states with two valence holes on different sites or on the same site, respectively. The S 2p photoemission doublets are observed at 162.7 and [approximately] 163.7 eV, their de-excitation giving rise to the SL[sub 2,3]VV Auger peak at 149.2 eV. The authors discuss the electronic interactions in the Li[sub 2]S[sub x] surface compound, and make a comparison with those in a Li-O surface compound.

  3. Synthesis, algal inhibition activities and QSAR studies of novel gramine compounds containing ester functional groups

    Institute of Scientific and Technical Information of China (English)

    LI Xia; YU Liangmin; JIANG Xiaohui; XIA Shuwei; ZHAO Haizhou

    2009-01-01

    2,5,6-Tribromo-l-methylgramine (TBG), isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its analogues with other ingredients in antifouling paints, structural modification of TBG was focused mainly on halogen substitution and N-substitution. Two halogen-substitute gramines and their derivatives which contain ester functional groups at N-position of gramines were synthesized. Algal inhibition activities of the synthesized compounds against algae Nitzschia closterium were evaluated and the Median Effective Concentration (EC50) range was 1.06-6.74 μg ml-1. Compounds that had a long chain ester group exhibited extremely high antifouling activity. Quantitive Structure Activity Relationship (QSAR) studies with multiple linear regression analysis were applied to find correlation between different calculated molecular descriptors and biological activity of the synthesized compounds. The results show that the toxicity (log (1/EC50)) is correlated well with the partition coefficient log P. Thus, these products have potential function as antifouling agents.

  4. Sweet scents from good bacteria: Case studies on bacterial volatile compounds for plant growth and immunity.

    Science.gov (United States)

    Chung, Joon-hui; Song, Geun Cheol; Ryu, Choong-Min

    2016-04-01

    Beneficial bacteria produce diverse chemical compounds that affect the behavior of other organisms including plants. Bacterial volatile compounds (BVCs) contribute to triggering plant immunity and promoting plant growth. Previous studies investigated changes in plant physiology caused by in vitro application of the identified volatile compounds or the BVC-emitting bacteria. This review collates new information on BVC-mediated plant-bacteria airborne interactions, addresses unresolved questions about the biological relevance of BVCs, and summarizes data on recently identified BVCs that improve plant growth or protection. Recent explorations of bacterial metabolic engineering to alter BVC production using heterologous or endogenous genes are introduced. Molecular genetic approaches can expand the BVC repertoire of beneficial bacteria to target additional beneficial effects, or simply boost the production level of naturally occurring BVCs. The effects of direct BVC application in soil are reviewed and evaluated for potential large-scale field and agricultural applications. Our review of recent BVC data indicates that BVCs have great potential to serve as effective biostimulants and bioprotectants even under open-field conditions.

  5. Experimental and computational studies of film cooling with compound angle injection

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, R.J.; Eckert, E.R.G.; Patankar, S.V. [Univ. of Minnesota, Minneapolis, MN (United States)] [and others

    1995-10-01

    The thermal efficiency of gas turbine systems depends largely on the turbine inlet temperature. Recent decades have seen a steady rise in the inlet temperature and a resulting reduction in fuel consumption. At the same time, it has been necessary to employ intensive cooling of the hot components. Among various cooling methods, film cooling has become a standard method for cooling of the turbine airfoils and combustion chamber walls. The University of Minnesota program is a combined experimental and computational study of various film-cooling configurations. Whereas a large number of parameters influence film cooling processes, this research focuses on compound angle injection through a single row and through two rows of holes. Later work will investigate the values of contoured hole designs. An appreciation of the advantages of compound angle injection has risen recently with the demand for more effective cooling and with improved understanding of the flow; this project should continue to further this understanding. Approaches being applied include: (1) a new measurement system that extends the mass/heat transfer analogy to obtain both local film cooling and local mass (heat) transfer results in a single system, (2) direct measurement of three-dimensional turbulent transport in a highly-disturbed flow, (3) the use of compound angle and shaped holes to optimize film cooling performance, and (4) an exploration of anisotropy corrections to turbulence modeling of film cooling jets.

  6. Reduction of Nitroaromatic Compounds on the Surface of Metallic Iron: Quantum Chemical Study

    Directory of Open Access Journals (Sweden)

    Jerzy Leszczynski

    2002-07-01

    Full Text Available Abstract: The initial reduction steps of nitroaromatic compounds on the surface of metallic iron have been studied theoretically using nitrobenzene (NB as a representative of nitroaromatic compounds. The quantum chemical cluster approximation within the semiempirical Neglect of Diatomic Differential Overlap for Metal Compounds method was applied to model the Fe(110 crystallographic surface, taken as a representative reactive surface for granular iron. This surface was modeled as a 39-atom two-layer metal cluster with rigid geometry. The associative and dissociative adsorption of nitrobenzene was considered. Based on our quantum chemical analysis, we suggest that the direct electron donation from the metal surface into the π* orbital of NB is a decisive factor responsible for subsequent transformation of the nitro group. Molecularly adsorbed NB interacts with metal iron exclusively through nitro moiety oxygens which occupy tri-coordinated positions on surface The charge transfer from metal to NB of approximately 2 atomic units destablizes the nitro group. As a result, the first dissociation of the N-O bond goes through a relatively low activation barrier. The adsorbed nitrosobenzene is predicted to be a stable surface species, though still quiet labile.

  7. A study of shielding properties of x-ray and gamma in barium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Seenappa, L.; Manjunatha, H. C. [Dept. of of Physics, Government College for women, Karnataka (India); Chandrika, B. M. [PC Extension, St. Annes School, Karnataka (India); Chikka, Hanumantharayappa [Vivekananda Degree College, Karnataka (India)

    2017-03-15

    Ionizing radiation is known to be harmful to human health. The shielding of ionizing radiation depends on the attenuation which can be achieved by three main rules, i.e. time, distance and absorbing material. The mass attenuation coefficient, linear attenuation coefficient, Half Value Layer (HVL) and Tenth Value Layer (TVL) of X-rays (32 keV, 74 keV) and gamma rays (662 keV) are measured in Barium compounds. The measured values agree well with the theory. The effective atomic numbers (Z{sub eff}) and electron density (Ne) of Barium compounds have been computed in the wide energy region 1 keV to 100 GeV using an accurate database of photon-interaction cross sections and the WinXCom program. The mass attenuation coefficient and linear attenuation coefficient for BaCO{sub 3} is higher than the BaCl{sub 2}, Ba(No{sub 3}){sub 2} and BaSO{sub 4}. HVL, TVL and mean free path are lower for BaCO{sub 3} than the BaCl{sub 2}, Ba(No{sub 3}){sub 2} and BaSO{sub 4}. Among the studied barium compounds, BaCO{sub 3} is best material for x-ray and gamma shielding.

  8. A QSAR, Pharmacokinetic and Toxicological Study of New Artemisinin Compounds with Anticancer Activity

    Directory of Open Access Journals (Sweden)

    Josinete B. Vieira

    2014-07-01

    Full Text Available The Density Functional Theory (DFT method and the 6-31G** basis set were employed to calculate the molecular properties of artemisinin and 20 derivatives with different degrees of cytotoxicity against the human hepatocellular carcinoma HepG2 line. Principal component analysis (PCA and hierarchical cluster analysis (HCA were employed to select the most important descriptors related to anticancer activity. The significant molecular descriptors related to the compounds with anticancer activity were the ALOGPS_log, Mor29m, IC5 and GAP energy. The Pearson correlation between activity and most important descriptors were used for the regression partial least squares (PLS and principal component regression (PCR models built. The regression PLS and PCR were very close, with variation between PLS and PCR of R2 = ±0.0106, R2ajust = ±0.0125, s = ±0.0234, F(4,11 = ±12.7802, Q2 = ±0.0088, SEV = ±0.0132, PRESS = ±0.4808 and SPRESS = ±0.0057. These models were used to predict the anticancer activity of eight new artemisinin compounds (test set with unknown activity, and for these new compounds were predicted pharmacokinetic properties: human intestinal absorption (HIA, cellular permeability (PCaCO2, cell permeability Maden Darby Canine Kidney (PMDCK, skin permeability (PSkin, plasma protein binding (PPB and penetration of the blood-brain barrier (CBrain/Blood, and toxicological: mutagenicity and carcinogenicity. The test set showed for two new artemisinin compounds satisfactory results for anticancer activity and pharmacokinetic and toxicological properties. Consequently, further studies need be done to evaluate the different proposals as well as their actions, toxicity, and potential use for treatment of cancers.

  9. First-principles study of Ni-Al intermetallic compounds under various temperature and pressure

    Science.gov (United States)

    Wen, Zhiqin; Zhao, Yuhong; Hou, Hua; Tian, Jinzhong; Han, Peide

    2017-03-01

    The pressure dependence behaviors of structural and mechanical properties as well as the effect of temperature on thermodynamic properties of Ni-Al ordered intermetallic compounds (i. e. Ni3Al, Ni5Al3, NiAl, Ni2Al3 and NiAl3) are investigated in details by implementing first-principles calculations. The calculated lattice parameters, bulk modulus and its pressure derivative are well in agreement with available experimental and theoretical values at zero pressure. All the compounds are mechanically stable with pressure going up to 50 GPa, and the volume change resistance of nickel aluminum alloys can be improved by increasing pressure and Ni concentration. The shear deformation resistance, elastic stiffness and microhardness of nickel aluminum alloys can be strengthened by increasing the content of Ni5Al3 and Ni2Al3, and pressure can also enhance these properties of Ni5Al3, NiAl and Ni2Al3. The ductility of Ni3Al, Ni5Al3 and NiAl can be improved by increasing pressure, while brittle nature turns into ductile nature in 20-30 GPa and 10-20 GPa for Ni2Al3 and NiAl3, respectively. Furthermore, the elastic anisotropy of Ni3Al, Ni5Al3, Ni2Al3 and NiAl3 enhances with pressure, while NiAl shows few change with pressure increasing. In addition, Ni3Al is the most sensitive to pressure change among considered compounds. Finally, the Debye temperature, linear thermal expansion coefficient and heat capacity of these compounds are calculated using the quasi-harmonic Debye model in pressure ranging from 0 to 50 GPa and temperature ranging from 0 to 1200 K to elucidate the relationships between thermodynamic parameters and temperature under various pressure. The results are helpful insights into the study of nickel aluminum alloys.

  10. Screening study of SFC critical method parameters for the determination of pharmaceutical compounds.

    Science.gov (United States)

    Dispas, Amandine; Lebrun, Pierre; Sacré, Pierre-Yves; Hubert, Philippe

    2016-06-05

    Nowadays, supercritical fluid chromatography is commonly presented as a promising alternative technique in the field of separation sciences. Nevertheless the selection of chromatographic conditions and sample preparation of pharmaceutical compounds remain a challenge and peak distortion was previously highlighted. The main objective of the present work was to evaluate the impact of different critical method parameters (CMPs), i.e. stationary phase, mobile phase composition and injection solvent nature. The experiments were performed considering two groups of antimalarial molecules: one group with neutral/apolar compounds and the other one with salt form of polar compounds. In this context, another objective was to propose a suitable sample solvent for quantitative analysis. The interest of new generation stationary phase to obtain good peak shape and the interest to tune the mobile phase composition were demonstrated. During this study, design of experiments and desirability function approach enabled to highlight optimal chromatographic conditions in order to maximise peak capacity and to get acceptable value of symmetry factor. Regarding sample injection solvent composition, some counterintuitive results were observed: solvents closer to the mobile phase polarity (i.e heptane or 2-propanol/heptane mixture) did not provide best results in terms of peak symmetry. In addition, acetonitrile and short aliphatic alcohols offered an interesting alternative as injection solvent: toxicity of solvents used is clearly reduced and better quantitative performances could be expected while keeping high peak capacity and symmetric sharp peaks. Finally, the quantitative performances were evaluated by the method validation for the quantitative determination of quinine sulfate in a pharmaceutical formulation. These better understandings on critical method parameters led SFC to be an even more promising technique in the field of the analysis of pharmaceutical compounds.

  11. Moessbauer and magnetic studies of the ternary compound FeIn{sub 2}Se{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Bodnar, I. V., E-mail: chemzav@bsuir.by; Pauliukavets, S. A. [Belarussian State University of Informatics and Radioelectronics (Belarus); Trukhanov, S. V. [National Academy of Sciences of Belarus, Scientific-Practical Materials Research Center (Belarus); Fedotova, Yu. A. [Belarus State University (Belarus)

    2012-05-15

    Single crystals of the ternary compound FeIn{sub 2}Se{sub 4} are grown by directional crystallization of the melt. The composition and structure of the single crystals are determined. The local states of iron ions in this compound are studied by nuclear {gamma}-resonance spectroscopy in transmission configuration. The temperature and field dependences of a specific magnetic moment for the ternary compound FeIn{sub 2}Se{sub 4} are measured in the temperature range 4-310 K in magnetic fields of 0-140 kOe. The reasons and mechanisms for magnetic state formation in single crystals of the obtained compound are discussed.

  12. Study of Biogenic Volatile Organic Compounds at the French Guiana Tropical Forest

    Science.gov (United States)

    Corain Lopes, Paula Regina; Guenther, Alex; Turnipseed, Andrew; Bonal, Damien; Serça, Dominique; Burban, Benôit; Siebicke, Lukas; Emmons, Louisa; Bustillos, José Oscar W. V.

    2013-04-01

    Biogenic volatile organic compound (BVOCs) emissions play an important role in regional air quality and global atmospheric chemistry. In addition, these natural VOC emissions serve important biological functions including attracting and repelling pollinators and herbivores. Some biological organisms use ambient air as a communication medium and the oxidation of these compounds brings about the concentration gradients sensed by insects and other organisms. Isoprene is the predominant BVOC emitted by vegetation and tropical forests are the dominant global source. This compound is very reactive in the atmosphere and contributes to the reactions that control tropospheric oxidant concentrations and thus the concentrations and lifetimes of longer-lived species. This paper presents a study on the seasonal variations in isoprene and some other significant BVOCs such as α-pinene, β-pinene, limonene, e-β ocimene and longifolene, measured at the Guyaflux Tower located in a wet tropical forest in Paracou French Guiana (5o16´54´´N, 52o54´44´´W), during the year of 2011, using the Relaxed Eddy Accumulation technique at approximately 20 meters high above the canopy. The results show a lower concentration of isoprene during the month of February and March which correspond to the wet season with an average of 0,545 μg/m3 and 0,341 μg/m3, respectively followed by a slight increase in middle April (still wet season) and a higher concentration later in mid-June. The same behavior was observed for α-pinene with higher concentrations for the same periods as isoprene however with a smaller increase. All the other compounds had concentrations below 1 μg/m3during the whole year. The monoterpene, e-β ocimene, was observed and is known as a stress compound but the vegetation at the site did not face any known severe stress condition such as excessive drought or flooding. Concerning the fluxes, the results showed that just a small amount of BVOCs were deposited by wet or dry

  13. An experimental study of hafting adhesives and the implications for compound tool technology.

    Science.gov (United States)

    Zipkin, Andrew M; Wagner, Mark; McGrath, Kate; Brooks, Alison S; Lucas, Peter W

    2014-01-01

    Experimental studies of hafting adhesives and modifications to compound tool components can demonstrate the extent to which human ancestors understood and exploited material properties only formally defined by science within the last century. Discoveries of Stone Age hafting adhesives at archaeological sites in Europe, the Middle East, and Africa have spurred experiments that sought to replicate or create models of such adhesives. Most of these studies, however, have been actualistic in design, focusing on replicating ancient applications of adhesive technology. In contrast, this study tested several glues based on Acacia resin within a materials science framework to better understand the effect of each adhesive ingredient on compound tool durability. Using an overlap joint as a model for a compound tool, adhesives formulated with loading agents from a range of particle sizes and mineral compositions were tested for toughness on smooth and rough substrates. Our results indicated that overlap joint toughness is significantly increased by using a roughened joint surface. Contrary to some previous studies, there was no evidence that particle size diversity in a loading agent improved adhesive effectiveness. Generally, glues containing quartz or ochre loading agents in the silt and clay-sized particle class yielded the toughest overlap joints, with the effect of particle size found to be more significant for rough rather than smooth substrate joints. Additionally, no particular ochre mineral or mineral mixture was found to be a clearly superior loading agent. These two points taken together suggest that Paleolithic use of ochre-loaded adhesives and the criteria used to select ochres for this purpose may have been mediated by visual and symbolic considerations rather than purely functional concerns.

  14. Selection of quantum chemical descriptors by chemometric methods in the study of antioxidant activity of flavonoid compounds

    Science.gov (United States)

    Weber, K. C.; Honório, K. M.; da Silva, S. L.; Mercadante, R.; da Silva, A. B. F.

    In the present study, the aim was to select electronic properties responsible for free radical scavenging ability of a set of 25 flavonoid compounds employing chemometric methods. Electronic parameters were calculated using the AM1 semiempirical method, and chemometric methods (principal component analysis, hierarchical cluster analysis, and k-nearest neighbor) were used with the aim to build models able to find relationships between electronic features and the antioxidant activity presented by the compounds studied. According to these models, four electronic variables can be considered important to discriminate more and less antioxidant flavonoid compounds: polarizability (α), charge at carbon 3 (QC3), total charge at substituent 5 (QS5), and total charge at substituent 3' (QS3'). The features found as being responsible for the antioxidant activity of the flavonoid compounds studied are consistent with previous results found in the literature. The results obtained can also bring improvements in the search for better antioxidant flavonoid compounds.

  15. First-principles study of the nickel–silicon binary compounds under pressure

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yuhong, E-mail: zyh388@sina.com [College of Materials Science and Engineering, North University of China, Taiyuan 030051 (China); Hou, Hua [College of Materials Science and Engineering, North University of China, Taiyuan 030051 (China); Zhao, Yuhui [Department of Mechanical and Electronic Engineering, Hebei College of Industry and Technology, Shijiazhuang 050091 (China); Han, Peide [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)

    2015-08-15

    Highlights: • The structural and elastic properties of Ni–Si system under pressure are firstly studied. • The lattice parameters of NiSi{sub 2} are the most sensitive to external pressure change. • Ni{sub 3}Si, Ni{sub 31}Si{sub 12}, Ni{sub 2}Si (δ) and Ni{sub 3}Si{sub 2} are mechanical stability with pressure up to 50 GPa. • The hardness of the four compounds can be improved by increasing pressure. • Electronic structures are analyzed to understand pressure effect on the seven compounds. - Abstract: The effects of high pressure on structural, stable, elastic, thermodynamic properties and electronic structures of Ni–Si binary compounds (i.e. β-Ni{sub 3}Si, γ-Ni{sub 31}Si{sub 12}, δ-Ni{sub 2}Si, θ-Ni{sub 2}Si, ε-Ni{sub 3}Si{sub 2}, ε-NiSi and α-NiSi{sub 2}) have been firstly studied by first-principles calculation based on density functional theory method within generalized gradient approximation. The calculated lattice parameters of the seven compounds at zero pressure and zero temperature agree well with the available experimental values and previous theoretical data. The values of V/V{sub 0} decrease with pressure going up to 50 GPa and the rate of change decrease gradually. The lattice parameters of NiSi{sub 2} are the most sensitive to external pressure change. Ni{sub 3}Si, Ni{sub 31}Si{sub 12}, Ni{sub 2}Si (δ) and Ni{sub 3}Si{sub 2} are mechanical stability by estimating stability criteria with pressure ranging from 0 to 50 GPa. But Ni{sub 2}Si (θ), NiSi and NiSi{sub 2} are not mechanically stable with pressure up to 10, 40 and 30 GPa, respectively. The calculated results of bulk modulus B, shear modulus G and Young’s modulus E illustrate pressure can improve the hardness of Ni{sub 3}Si, Ni{sub 31}Si{sub 12}, Ni{sub 2}Si (δ) and Ni{sub 3}Si{sub 2} compounds. In addition, ratio of shear modulus to bulk modulus G/B shows that all the considered compounds are ductile materials except NiSi. The Debye temperature Θ{sub D} of Ni{sub 3}Si

  16. Band structure of Heusler compounds studied by photoemission and tunneling spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Arbelo Jorge, Elena

    2011-07-01

    Heusler compounds are key materials for spintronic applications. They have attracted a lot of interest due to their half-metallic properties predicted by band structure calculations. The aim of this work is to evaluate experimentally the validity of the predictions of half metallicity by band structure calculations for two specific Heusler compounds, Co{sub 2}FeAl{sub 0.3}Si{sub 0.7} and Co{sub 2}MnGa. Two different spectroscopy methods for the analysis of the electronic properties were used: Angular Resolved Ultraviolet Photoemission Spectroscopy (ARUPS) and Tunneling Spectroscopy. Heusler compounds are prepared as thin films by RF-sputtering in an ultra high vacuum system. For the characterization of the samples, bulk and surface crystallographic and magnetic properties of Co{sub 2}FeAl{sub 0.3}Si{sub 0.7} and Co{sub 2}MnGa are studied. X-ray and electron diffraction reveal a bulk and surface crossover between two different types of sublattice order (from B2 to L2{sub 1}) with increasing annealing temperature. X-ray magnetic circular dichroism results show that the magnetic properties in the surface and bulk are identical, although the magnetic moments obtained are 5 % below from the theoretically predicted. By ARUPS evidence for the validity of the predicted total bulk density of states (DOS) was demonstrated for both Heusler compounds. Additional ARUPS intensity contributions close to the Fermi energy indicates the presence of a specific surface DOS. Moreover, it is demonstrated that the crystallographic order, controlled by annealing, plays an important role on broadening effects of DOS features. Improving order resulted in better defined ARUPS features. Tunneling magnetoresistance measurements of Co{sub 2}FeAl{sub 0.3}Si{sub 0.7} and Co{sub 2}MnGa based MTJ's result in a Co{sub 2}FeAl{sub 0.3}Si{sub 0.7} spin polarization of 44 %, which is the highest experimentally obtained value for this compound, although it is lower than the 100 % predicted. For Co

  17. Study on Z-H/BMP Toughened Compound Artificial Bone and Its Osteogenesis

    Institute of Scientific and Technical Information of China (English)

    XU Wei-guo; CHEN An-min; SUN Shu-zhen

    2003-01-01

    The purpose of this study was to find a kind of new artificial bone for anterior spinal fusion.ZrO2 stabilized by Y2O3 ( Y- PSZ), porous hydroxyapatite ( HA ) and bone morphogenetic protein (BMP) were used to make artificial compound bone ( Y2O3 ) ZrO2 -HA/ BMP( Z-H/ BMP ) , whose function was tested, microstructure and mineralogic composition constitution were analysised by SEM and XRD , and the corresponding animal tests were porformed. Osteogenesis of the material was observed by eyes, histology and SEM. Experimental results show that the component and ossific activity of Z-H/BMP were satisfactory.

  18. Experimental and theoretical study on the inhibition performance of triazole compounds for mild steel corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Musa, Ahmed Y., E-mail: ahmed.musa@ymail.co [Department of Chemical and Process Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor (Malaysia); Kadhum, Abdul Amir H.; Mohamad, Abu Bakar; Takriff, Mohd Sobri [Department of Chemical and Process Engineering, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor (Malaysia)

    2010-10-15

    A relationship between quantum chemical parameters for three triazole compounds and their inhibition ability was studied using electrochemical measurements (potentiodynamic polarization and EIS), molecular dynamic method and quantum chemical calculations. Electrochemical measurements results revealed that the inhibition efficiencies increased with the concentration of inhibitors. The molecular dynamic method results showed that the higher interaction potential between the inhibitor and metal surface, the higher the inhibition efficiency. The quantum chemical calculation results showed that the triazole ring is the active site in these inhibitors and they can absorb on Fe surface by donating electrons to Fe d-orbital.

  19. Electronic and thermal properties of TiFe{sub 2} compound: An ab initio study

    Energy Technology Data Exchange (ETDEWEB)

    Sathyakumari, V. S.; Sankar, S., E-mail: drshreemit@gmail.com; Mahalakshmi, K.; Subashree, G.; Krithiga, R. [Condensed Matter Laboratory, Department of Physics, Madras Institute of Technology Campus, Anna University, Chennai-600044, Tamilnadu (India)

    2015-06-24

    A systematic study of electronic, and thermal properties such as the Density of states, Fermi energy, Debye temperature and specific heat coefficient, has been carried out using the results of electronic bandstructure and related characteristics of the Laves phase compound, TiFe{sub 2}. Computation of electronic bandstructure and associated properties has been carried out using the tight-binding-linear-muffin-tin-orbital (TB-LMTO) method within atomic sphere approximation (ASA). The calculated values are compared with the available results of literature.

  20. A QSPR STUDY OF NORMAL BOILING POINT OF ORGANIC COMPOUNDS (ALIPHATIC ALKANES USING MOLECULAR DESCRIPTORS

    Directory of Open Access Journals (Sweden)

    B. Souyei

    2013-12-01

    Full Text Available A quantitative structure–property relationship (QSPR study is carried out to develop correlations that relate the molecular structures of organic compounds (Aliphatic Alkanes to their normal boiling point (NBP and two correlations were proposed for constitutionals and connectivity indices Models. The correlations are simple in application with good accuracy, which provide an easy, direct and relatively accurate way to calculate NBP. Such calculation gives us a model that gives results in remarkable correlations with the descriptors of blokes constitutionals (CON, and connectivity indices (CI (R2 = 0.950, δ = 0.766 (R2 = 0.969, δ = 0.782 respectively.

  1. Carbon-13 and tin-119 relaxation studies of some axially symmetrical organotin compounds

    Science.gov (United States)

    Chapelle, S.; Granger, P.

    We have studied a variety of axially symmetrical tin compounds by 119Sn and 13C NMR. Tin was observed at two field strengths and, except for Ph 3SnCl, T1 is field independent and governed mainly by spin-rotation. A chemical-shift anisotropy of 136 ppm is observed for 119Sn in Ph 3SnCl. Deverell's relationship provides a good estimate of the values of the spin-rotational constants and the theory of Woessner, Snowden, and Huntress leads to the values of the rotational diffusion constants.

  2. Study on the basic nitrogen compounds from coal-derived oil

    Institute of Scientific and Technical Information of China (English)

    Xiao-hui GU; Xue-feng MAO; Yuan ZHAO; Wen-bo LI; Xiao-jing ZHANG

    2013-01-01

    The distillation range analysis and elemental analysis of fractioned direct liquefied oil were conducted.Each fraction of liquefied oil contains some nitrogen compounds.Using the acid extraction method and gas chromatography/mass spectrometry (GC-MS),the basic nitrogen compounds have been separated and identified.Compared with the nitrogen content of the liquefied oil before and after separation,the basic nitrogen compounds account for more than half of all nitrogen compounds.The basic nitrogen compounds in the light liquefied oil are easily separated,and contain more types of basic nitrogen compounds.The results also show that there are many basic nitrogen compounds in liquefied oil,such as pyrrole,aniline,pyridine,quinoline and so on.However,there are fewer other types of basic nitrogen compounds.

  3. Theoretical studies on new potential high energy density compounds (HEDCs) adamantyl nitrates from gas to solid

    Institute of Scientific and Technical Information of China (English)

    XU XiaoJuan; ZHU WeiHua; GONG XueDong; XIAO HeMing

    2008-01-01

    A series of adamantyl nitrates have been theoretically studied from gas to solid to search for new po-tential high energy density compounds (HEDCs). The heats of formation (HOFs) for the 26 title com-pounds were calculated by designing isodesmic reactions at the B3LYP/6-31G* level. It was found that the HOFs of the 26 isomers with the same number of -ONO2 groups (n) are not correlated well with the corresponding substituted positions. According to the obtained heats of detonation (Q), detonation velocities (D), and detonation pressures (P) using the Kamlet-Jacobs equations, it was found that when n=7~8, the adamantyl nitrates meet the criterion as an HEDC. The calculations on bond dissociation energies of O-N (EO-N) showed that the adamantyl nitrates with gemi -ONO2always have the worst stability among the isomers, and all the adamantyl nitrates with gemi -ONO2 have similar stability. Due to the complexity of their structures, values of Eo-, do not decrease with the increase of the substituent number n obviously, and the stability of adamantyl nitrates is not determined by only one structural parameter. Considering the stability requirement, only 1,2,4,6,8,9,10-adamantyl heptanitrate is recom-mended as a feasible HEDC. Molecular packing searching for 1,2,4,6,8,9,10-adamantyl heptanitrate among 7 most possible space groups (P21/c, P-1, P212121, P21, Pbca, C2/c, and Pna21) using Compass and Dreiding force fields showed that this compound tends to crystallize in P21/c. Ab initio periodic calculations on the electronic structure of the predicted packing showed that the O-NO2 bond is the trigger bond during thermolysis, which agrees with the result derived from the study of dissociation energies of O-N bonds.

  4. Structural and property studies on metal–organic compounds with 3-D supramolecular network

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qi-Ying; Ma, Ke-Fang; Xiao, Hong-Ping; Li, Xin-Hua; Shi, Qian, E-mail: shiq@wzu.edu.cn

    2014-07-01

    Two carboxylato-bridged allomeric compounds, ([Cu{sub 2}(dbsa){sub 2}(hmt) (H{sub 2}O){sub 4}]{sub 1/2}·2H{sub 2}O){sub n} (1), ([Ni(dbsa)(H{sub 2}O){sub 2}]{sub 1/2}[Ni(dbsa)(hmt)(H{sub 2}O){sub 2}]{sub 1/2}·2H{sub 2}O){sub n} (2) (H{sub 2}dbsa=meso-2,3-dibromosuccinic acid, hmt=hexamethylenetetramine) have been synthesized and characterized by X-ray structral analyses. The metal ions have two kinds of coordination fashion in one unit, and bridged by carboxylate and hmt ligands along with weak interactions existing in the solid structure, forming a 3-D supramolecular network. Variable-temperature magnetic property studies reveal the existence of antiferromagnetic interactions in 1 and 2 with g=2.2, J{sub 1}=−3.5 cm{sup −1}, J{sub 2}=−2.8 cm{sup −1} for 1, and g=2.1, J=−3.5 cm{sup −1} for 2. - Graphical abstract: Variable-temperature magnetic property studies of two 3-D supramolecular compounds reveal the existence of antiferromagnetic interactions between the metal ions, through the effective super-exchange media. - Highlights: • Two 3-D allomeric Cu(II) and Ni(II) metal–organic compounds have been prepared. • The 3-D networks were constructed by coordination bonds, weak interactions and hydrogen bond interactions. • There are antiferromagnetic super-exchange interactions between the metal ions.

  5. Thermodynamic Properties of Compressed CuX (X = Cl, Br) Compounds: Ab Initio Study

    Science.gov (United States)

    Bioud, Nadhira; Kassali, Kamel; Bouarissa, Nadir

    2017-04-01

    A pseudopotential plane wave method based on the density functional theory has been employed to study some thermodynamic properties of copper chloride (CuCl) and copper bromide (CuBr) compounds under the effect of temperature and pressure. The phase transition pressure, the unit cell volume, the isothermal bulk modulus, the constant volume heat capacity, the entropy, the Debye temperature, the Grüneisen parameter and the volumetric thermal expansion coefficient are studied in the pressure range 0-10 GPa, and for temperatures ranging from 0 K up to 650 K and 750 K for CuCl and CuBr, respectively. The phase transition pressure is found to be around 7.8 and 6.95 GPa for CuCI and CuBr, respectively. These values are respectively in reasonably good agreement with the experimental ones of 8.2 GPa and 6.8 GPa reported in the literature. Moreover, at room temperature and zero pressure, the heat capacity at constant volume and the Grüneisen parameter of both compounds of interest are found to be in good agreement with the available experimental and theoretical data. The information gathered from the present investigation may be useful for the study of the behavior of the fundamental properties of CuCI and CuBr under the influence of high temperature and pressure.

  6. Structure-activity relationship study of novel anticancer aspirin-based compounds.

    Science.gov (United States)

    Joseph, Stancy; Nie, Ting; Huang, Liqun; Zhou, Hui; Atmakur, Krishnaiah; Gupta, Ramesh C; Johnson, Francis; Rigas, Basil

    2011-01-01

    We performed a structure-activity relationship (SAR) study of a novel aspirin (ASA) derivative, which shows strong anticancer activity in vitro and in vivo. A series of ASA-based benzyl esters (ABEs) were synthesized and their inhibitory activity against human colon (HT-29 and SW480) and pancreatic (BxPC-3 and MIA PaCa-2) cancer cell lines was evaluated. The ABEs that we studied largely comprise organic benzyl esters bearing an ASA or acyloxy group (X) at the meta or para position of the benzyl ring and one of four different leaving groups. The nature of the salicyloyl/acyloxy function, the leaving group, and the additional substituents affecting the electron density of the benzyl ring, all were influential determinants of the inhibitory activity on cancer cell growth for each ABE. Positional isomerism also played a significant role in this effect. The mechanism of action of these compounds appears consistent with the notion that they generate either a quinone methide or an m-oxybenzyl zwitterion (or an m-hydroxybenzyl cation), which then reacts with a nucleophile, mediating their biological effect. Our SAR study provides an insight into the biological properties of this novel class of compounds and underscores their potential as anticancer agents.

  7. Quantitative global studies of reactomes and metabolomes using a vectorial representation of reactions and chemical compounds

    Directory of Open Access Journals (Sweden)

    Triviño Juan C

    2010-04-01

    Full Text Available Abstract Background Global studies of the protein repertories of organisms are providing important information on the characteristics of the protein space. Many of these studies entail classification of the protein repertory on the basis of structure and/or sequence similarities. The situation is different for metabolism. Because there is no good way of measuring similarities between chemical reactions, there is a barrier to the development of global classifications of "metabolic space" and subsequent studies comparable to those done for protein sequences and structures. Results In this work, we propose a vectorial representation of chemical reactions, which allows them to be compared and classified. In this representation, chemical compounds, reactions and pathways may be represented in the same vectorial space. We show that the representation of chemical compounds reflects their physicochemical properties and can be used for predictive purposes. We use the vectorial representations of reactions to perform a global classification of the reactome of the model organism E. coli. Conclusions We show that this unsupervised clustering results in groups of enzymes more coherent in biological terms than equivalent groupings obtained from the EC hierarchy. This hierarchical clustering produces an optimal set of 21 groups which we analyzed for their biological meaning.

  8. Magnetic and specific heat studies of the frustrated Er2Mn2O7 compound

    Institute of Scientific and Technical Information of China (English)

    N.Ben Amor; M.Bejar; E.Dhahri; M.A.Valente; P.Lachkar; E.K.Hlil

    2013-01-01

    A new Er2Mn2O7 compound was synthesized by the ceramic method and its crystal structure was characterized using powder X-ray diffraction (XRD) and observed by scanning electron microscopy (SEM).The magnetic properties were investigated using a BS2 magnetometer and the heat capacity was studied using a quantum design (PPMS).The structural study revealed that this compound was monophasic and crystallized in the monclinic system with the P2/M space group.Magnetization measurements were carried out in the temperature range of 1.8-200 K under an applied magnetic field of 0.05 T.A crossover from a room temperature paramagnetic phase to an antiferromagnetic one at low temperature was detected from the magnetic study.The magnetic susceptibility,in the paramagnetic region above 40 K,was found to present a simple Curie-Weiss type behavior.From the specific heat (CP) measurements in magnetic fields up to 5 T,we noted the presence of a wide peak characteristic of a second order magneto-structural transition.

  9. Design, synthesis and molecular docking studies of novel triazole antifungal compounds

    Institute of Scientific and Technical Information of China (English)

    Qiu Qin He; Ke Li; Yong Bing Cao; Huan Wen Dong; Li Hua Zhao; Chao Mei Liu; Chun Quan Sheng

    2007-01-01

    Based on the active site of Candida albicans lanosterol 14α-demethylase (CACYP51), novel triazole compounds structurally different from the current triazole drugs were designed and synthesized.In vitro antifungal activities showed that compounds 10,11,16 and 20 exhibited strong activities.In addition, compounds 10,11 and 16 also displayed certain activities against fluconazole-resistant fungi.

  10. The Study of Interactions between Active Compounds of Coffee and Willow (Salix sp. Bark Water Extract

    Directory of Open Access Journals (Sweden)

    Agata Durak

    2014-01-01

    Full Text Available Coffee and willow are known as valuable sources of biologically active phytochemicals such as chlorogenic acid, caffeine, and salicin. The aim of the study was to determine the interactions between the active compounds contained in water extracts from coffee and bark of willow (Salix purpurea and Salix myrsinifolia. Raw materials and their mixtures were characterized by multidirectional antioxidant activities; however, bioactive constituents interacted with each other. Synergism was observed for ability of inhibition of lipid peroxidation and reducing power, whereas compounds able to scavenge ABTS radical cation acted antagonistically. Additionally, phytochemicals from willow bark possessed hydrophilic character and thermostability which justifies their potential use as an ingredient in coffee beverages. Proposed mixtures may be used in the prophylaxis or treatment of some civilization diseases linked with oxidative stress. Most importantly, strong synergism observed for phytochemicals able to prevent lipids against oxidation may suggest protective effect for cell membrane phospholipids. Obtained results indicate that extracts from bark tested Salix genotypes as an ingredient in coffee beverages can provide health promoting benefits to the consumers; however, this issue requires further study.

  11. The study of interactions between active compounds of coffee and willow (Salix sp.) bark water extract.

    Science.gov (United States)

    Durak, Agata; Gawlik-Dziki, Urszula

    2014-01-01

    Coffee and willow are known as valuable sources of biologically active phytochemicals such as chlorogenic acid, caffeine, and salicin. The aim of the study was to determine the interactions between the active compounds contained in water extracts from coffee and bark of willow (Salix purpurea and Salix myrsinifolia). Raw materials and their mixtures were characterized by multidirectional antioxidant activities; however, bioactive constituents interacted with each other. Synergism was observed for ability of inhibition of lipid peroxidation and reducing power, whereas compounds able to scavenge ABTS radical cation acted antagonistically. Additionally, phytochemicals from willow bark possessed hydrophilic character and thermostability which justifies their potential use as an ingredient in coffee beverages. Proposed mixtures may be used in the prophylaxis or treatment of some civilization diseases linked with oxidative stress. Most importantly, strong synergism observed for phytochemicals able to prevent lipids against oxidation may suggest protective effect for cell membrane phospholipids. Obtained results indicate that extracts from bark tested Salix genotypes as an ingredient in coffee beverages can provide health promoting benefits to the consumers; however, this issue requires further study.

  12. A concise review of applications of micellar liquid chromatography to study biologically active compounds.

    Science.gov (United States)

    Stępnik, Katarzyna E

    2017-01-01

    The features of micellar systems are outstanding compared with conventional RP-LC ones. Therefore, the unique properties of micellar chromatography (MLC) are widely recognized. In this short review the applicability of MLC as an in vitro method for the determination of biological activity is discussed. For this purpose many specific examples of MLC applications supported by the theoretical backgrounds of the cited biological activity areas as well as the factors affecting them are presented. This study collects and organizes the most important references of bioactivity determination which were created both recently and in the past, using the MLC method. Although there are many papers on the MLC there is no literature review focused particularly on its applicability in the study of biological activity of various compounds. This work can be treated as a significant review of so far published papers which particularly emphasizes the importance of MLC as in vitro method for determination of bioactivity of different compounds. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Laboratory Study on Properties of Diatomite and Basalt Fiber Compound Modified Asphalt Mastic

    Directory of Open Access Journals (Sweden)

    Yongchun Cheng

    2017-01-01

    Full Text Available In order to improve the performance of asphalt mastic, some researchers have added diatomite or basalt fiber as a modifier to the asphalt mastic, and the results show that some properties of the asphalt mastic were improved. For the simultaneous addition of diatomite and basalt fiber, two kinds of modifier, compound modified asphalt mastic had not been reported; in this paper, thirteen groups of diatomite and basalt fiber (DBFCMAM compound modified asphalt mastic with different content were prepared to study the performance. Softening point, cone penetration, viscosity, and DSR tests were conducted, for the high temperature performance evaluation of DBFCMAM, whereas force ductility and BBR tests were used in the low temperature performance study of the DBFCMAM. The results demonstrated that the high temperature performance of DBFCMAM was increased; moreover, the low temperature performance of DBFCMAM improved by diatomite and basalt fiber according to the results of the force ductility test; however, the conclusion of the BBR test data was inconsistent with the force ductility test. In summary, the high temperature and low temperature properties of DBFCMAM had been improved.

  14. Study of flavour compounds from orange juices by HS-SPME and GC-MS

    Science.gov (United States)

    Schmutzer, G.; Avram, V.; Covaciu, F.; Feher, I.; Magdas, A.; David, L.; Moldovan, Z.

    2013-11-01

    The flavour of the orange juices, which gives the taste and odour of the product, is an important criterion about the products quality for consumers. A fresh single strength and two commercial orange juices (obtained from concentrate) flavour profile were studied using a selective and sensitive gas chromatography - mass spectrometry (GC-MS) analytical system, after a solvent free, single step preconcentration and extraction technique, the headspace solid phase microextraction (HP-SPME). In the studied orange juices 55 flavour compounds were detected and classified as belonging to the esters, alcohols, ketones, monoterpenes and sesquiterpenes chemical families. The fresh single strength orange juice was characterized by high amount of esters, monoterpenes and sesquiterpenes. Limonene and valencene were the most abundant flavours in this fresh natural orange juice. Alcohols and ketones were found in higher concentration in the commercial orange juices made from concentrate, than in the single strength products. Nevertheless, in commercial juices the most abundant flavour was limonene and α-terpineol. The results highlight clear differences between fresh singles strength orange juice and juice from concentrate. The orange juices reconstructed from concentrate, made in Romania, present low quantity of flavour compounds, suggesting the absence or a low rearomatization process, but extraneous components were not detected.

  15. Pathways in coal thermolysis: a theoretical and experimental study with model compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ekpenyong, I.A.; Virk, P.S.

    1982-01-01

    Fundamental aspects of coal thermolysis were investigated, including how the chemical structures of aromatics, hydroaromatics, and alcohols affect their reactivities as hydrogen donors and acceptors in coal processing. The susceptibilities of substructural entities in coals to fragmentation via a number of thermal pericyclic and free radical mechanisms were probed, as were the factors governing relative reactivities within series of such coal model compounds. The theoretical part of the work applied perturbation molecular orbital (PMO) and frontier orbital theories, in conjunction with ..pi..- and pseudo-..pi.. MO's, to the study of model compound reactivity. This enabled prediction of reactivity patterns of H-donors, H-acceptors and coal-like structures as functions of their ..pi..- and sigma-bond configurations, including heteroatomic effects. Experimentally, the liquid phase reactions of the coal model compound PhOCH/sub 2/Ph (Benzyl phenyl ether, BPE) were detailed for the first time in each of four hydronaphthalene H-donor solvents in the temperature range 220/sup 0/ to 300/sup 0/C. The thermolysis of BPE exhibited a pronounced dependence on solvent structure, both with respect to product selectivities and reaction kinetics. BPE thermolysis pathways were delineated as involving (a) rearrangement, leading to isomerization, (b) hydrogenations, leading ultimately to PhOH and PhCH/sub 3/ products, and (c) addition reactions, engendering heavy products. Pathways (b) and (c) are competitive and, in each, self-reactions of BPE-derivatives vie against reactions between these and the donor solvent. Of the detailed free radical and pericyclic reaction mechanisms postulated, the latter rationalized many more facets of the BPE results than the former. The theoretical and experimental results were appraised against previous coal thermolysis literature.

  16. A clinical comparative study of the management of chronic renal failure with Punarnavadi compound.

    Science.gov (United States)

    Prashanth, G S; Baghel, M S; Ravishankar, B; Gupta, S N; Mehta, Miten P

    2010-04-01

    India like any other country is facing a silent epidemic of chronic renal failure (CRF)- a facet of the health transition associated with industrialization partly fuelled by increase in sedentary lifestyle, low birth weight and malnutrition. Increasing figures by many folds seen is posing a difficult situation to overcome with respect to economy and health of the working and earning population of the nation. There is an urgent need to explore, highlight new interventions and modify modifiable risk factors as a basis for treatment strategies to prevent the development and progression of CRF. The present study was taken up to evaluate the role of trial formulation tab. Punarnavadi compound in the management of chronic renal failure. This was an open clinical comparative study in controlled circumstances wherein 67 patients were studied for two months in three groups- Group A (allopathic control), Group B (ayurvedic control) and Group C (ayurvedic test). It was a multi-centric study; patients were registered from Anandababa charitable dialysis centre, Jamnagar, Kayachikitsa O.P.D. of I.P.G.T. and R.A. Jamnagar and P. D. Patel Ayurveda hospital, Nadiad. Results were assessed on 15 parameters using Students (paired) 't' test. Group A patients showed comparatively better results in eight parameters- weight, platelet count, serum urea, serum uric acid, serum sodium, potassium, chloride and total proteins. Parameter Hemoglobin% showed better results in Group B patients and in Group C patients comparatively better results in six parameters viz.- quality of life (breathlessness, weakness, general functional capacity), total count, serum creatinine and serum calcium - were observed. Throughout the study, trial drug tab. Punarnavadi compound did not show any adverse drug reaction. The results of this study will help in developing a cheap and safe treatment for the management of CRF.

  17. Synchrotron Diffraction Studies of Spontaneous Magnetostriction in Rare Earth Transition Metal Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ning [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    Thermal expansion anomalies of R2Fe14B and R2Fe17Cx (x = 0,2) (R = Y, Nd, Gd, Tb, Er) stoichiometric compounds are studied with high-energy synchrotron X-ray powder diffraction using Debye-Schemer geometry in temperature range 10K to 1000K. Large spontaneous magnetostriction up to their Curie temperatures (Tc) is observed. The a-axes show relatively larger invar effects than c-axes in the R2Fe14B compounds whereas the R2Fe17Cx show the contrary anisotropies. The iron sub-lattice is shown to dominate the spontaneous magnetostriction of the compounds. The contribution of the rare earth sublattice is roughly proportional to the spin magnetic moment of the rare earth in the R2Fe14B compounds but in R2Fe17Cx, the rare earth sub-lattice contribution appears more likely to be dominated by the local bonding. The calculation of spontaneous magnetostrain of bonds shows that the bonds associated with Fe(j2) sites in R2Fe14B and the dumbbell sites in R2Fe17Cx have larger values, which is strongly related to their largest magnetic moment and Wigner-Seitz atomic cell volume. The roles of the carbon atoms in increasing the Curie temperatures of the R2Fe17 compounds are attributed to the increased separation of Fe hexagons. The R2Fe17 and R2Fe14B phases with magnetic rare earth ions also show anisotropies of thermal expansion above c. For R2Fe17 and R2Fe14B the a a/a c > 1 whereas the anisotropy is reversed with the interstitial carbon in R2Fe17. The average bond magnetostrain is shown to be a possible predictor of the magnetic moment of Fe sites in the compounds. Both of the theoretical and

  18. 3D-quantitative structure-activity relationship study of organophosphate compounds

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jinsong; WANG Bin; DAI Zhaoxia; WANG Xiaodong; KONG Lingren; WANG Liansheng

    2004-01-01

    The biological effects of most organophosphate compounds (OP) are arising by inhibition of the enzyme acetylcholinesterase (AChE). The 3D-quantitative structure-activity relationship (3D-QSAR) on the acute toxicity to housefly (Musca nobulo L.) of 35 dialkyl phenyl phosphate compounds are studied by using comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) methods, and the reaction mechanism between the OP and the AChE are discussed. In contrast to classical QSAR methods, CoMFA and CoMSIA, especially the combination of both approaches, can give more comprehensive and accurate perspectives on the mechanism of the reaction between OP and AChE. The results show that the length of alkyl, and the electronegative of substituent on phenyl of OP have significant effects on the AChE activity, whereas, the hydrophobicity of OP has little influence. The steric and electronic properties of OP have a dominant influence on the reaction between OP and AChE.

  19. A SAR and QSAR Study of New Artemisinin Compounds with Antimalarial Activity

    Directory of Open Access Journals (Sweden)

    Cleydson Breno R. Santos

    2013-12-01

    Full Text Available The Hartree-Fock method and the 6-31G** basis set were employed to calculate the molecular properties of artemisinin and 20 derivatives with antimalarial activity. Maps of molecular electrostatic potential (MEPs and molecular docking were used to investigate the interaction between ligands and the receptor (heme. Principal component analysis and hierarchical cluster analysis were employed to select the most important descriptors related to activity. The correlation between biological activity and molecular properties was obtained using the partial least squares and principal component regression methods. The regression PLS and PCR models built in this study were also used to predict the antimalarial activity of 30 new artemisinin compounds with unknown activity. The models obtained showed not only statistical significance but also predictive ability. The significant molecular descriptors related to the compounds with antimalarial activity were the hydration energy (HE, the charge on the O11 oxygen atom (QO11, the torsion angle O1-O2-Fe-N2 (D2 and the maximum rate of R/Sanderson Electronegativity (RTe+. These variables led to a physical and structural explanation of the molecular properties that should be selected for when designing new ligands to be used as antimalarial agents.

  20. Ab initio computational study of vincristine as a biological active compound: NMR and NBO analyses

    Directory of Open Access Journals (Sweden)

    Shiva Joohari

    2015-06-01

    Full Text Available Vincristine is a biological active alkaloid that has been used clinically against a variety of neoplasms. In the current study we have theoretically investigated the magnetic properties of titled compound to predict physical and chemical properties of vincristine as a biological inhibitor. Ab initio computation using HF and B3LYP with 3-21G(d and 6-31G(d level of theory have been performed and then magnetic shielding tensor (, ppm, shielding asymmetry (, magnetic shielding anisotropy (aniso, ppm, the skew of a tensor (K, chemical shift anisotropy ( and chemical shift ( were calculated to indicate the details of the interaction mechanism between microtubules and vincristine. Moreover, EHOMO, ELUMO and Ebg were evaluated. The maximum and minimum values of Ebg were found in HF/3-21g and B3LYP/3-21g respectively. It was also uggested that O24, O37, O49 and O55 with minimum values of iso, are active sites of titled compound. Furthermore the calculated chemical shifts were compared with experimental data in DMSO and CDCl3 solvents.

  1. A comparative DFT study on the antioxidant activity of apigenin and scutellarein flavonoid compounds

    Science.gov (United States)

    Sadasivam, K.; Kumaresan, R.

    2011-03-01

    The potent antioxidant activity of flavonoids relevant to their ability to scavenge reactive oxygen species is the most important function of flavonoids. Density functional theory calculations were explored to investigate the antioxidant activity of flavonoid compounds such as apigenin and scutellarein. The biological characteristics are dependent on electronic parameters, describing the charge distribution on the rings of the flavonoid molecules. The computation of structural and various molecular descriptors such as polarizability, dipole moment, energy gap, homolytic O-H bond dissociation enthalpies (BDEs), ionization potential (IP), electron affinity, hardness, softness, electronegativity, electrophilic index and density plot of molecular orbital for neutral as well as radical species were carried out and studied. The B3LYP/6-311G(d,p) basis set was adopted for all the computations. This computation reveals that scutellarein exhibits higher degree of antioxidant activity than apigenin. Their dipole moment and polarizability analysis show that both the compounds are polar in nature and have the capacity to polarize other atoms.

  2. Applications of HPLC-MS in compound Ilex pubescens extract study

    Institute of Scientific and Technical Information of China (English)

    Yang Yunyun; Hongwei Chen; Zhong Ming; Ma Zhiling; Teng Jiuwei; Mu Dehai

    2006-01-01

    In this paper,high performance liquid chromatography(HPLC)along with mass spectrometry (MS)and HPLC along with a diode array detector(DAD)was used to study the compound flex pubescens extract.Two ionization techniques:electro spray ionization(ESI)and atmospheric pressure chemical ionization(APCI)were used in this work.The liquid chromatograms obtained by DAD,total ion chromatograms(TIC)from positive-and negative-ion ESI-MS and the positive-and negative-ion APCI-MS were compared.The liquid chromatograms obtained by TIC from ESI-MS provided more information on chromatographic peaks than those obtained by DAD or TIC from APCI-MS.It is suggested that the fingerprints of the compound Ilex pubescens extract should be provided by the liquid chromatograms obtained by DAD together with TIC from the negative-ion ESI-MS.The molecular weights of the nine main components in an HPLC-DAD chromatogram were determined by the corresponding positive-and negative-ion ESI and the positive-and negative-ion APCI mass spectra information.In the liquid chromatogram obtained by TIC from the negative-ion ESI-MS,the molecular weights of 23 main components were determined based on the corresponding positive-and negative-ion ESI mass spectra information.

  3. Study of the Influence of Different Diphenol Compounds on Soil Microbial Activity by Microcalorimetry

    Institute of Scientific and Technical Information of China (English)

    CHEN, Huilun; YAO, Jun; WANG, Fei; GYULA, Zaray

    2009-01-01

    Microcalorimetry was applied to follow the toxic effects caused by different diphenol compounds on microbial activity of Chinese fir soil. The activity of the microorganisms in soil was stimulated by adding 0.3 mL of a nutrient solution containing 2.5 mg of glucose and 2.5 mg of ammonium sulfate and the measurements were performed under a 35% controlled humidity at 28 ℃. Power-time curves recorded on a microcalorimeter were followed by increasing the amount of diphenol compounds, which affected directly the total thermal effects evolved by the microorganisms. The curves showed a synergism on total thermal effect obtained by the addition of 2000 mg·kg~(-1) of resorcinol, causing a consumption of resorcinol by the microorganisms as a new source of nutrients. Above this dose,the total thermal effect decreased exponentially. However, the addition of catechol and hydroquinone caused the total thermal effects to decrease directly. It was concluded that the increase in the diphenol concentration strongly affected the microbial life in this ecosystem. Microcalorimetry appears as a suitable technique to carry out both qualitative and quantitative comparative studies of microbial activity in soil.

  4. Electronic structures of melatonin and related compounds studied by photoelectron spectroscopy

    CERN Document Server

    Kubota, M

    2003-01-01

    Melatonin is a hormone structurally regarded as being composed of a 5-methoxyindole group and an N-ethylacetamide group; its various physiological activities have attracted a great deal of attention recently. The gas phase He(I) photoelectron spectra of melatonin (M) and its related compounds including N-acetylserotonin have been studied with the aid of molecular orbital calculations. The first photoelectron spectral band group of compound M is ascribed to ionizations from the two pi orbitals localized on the methoxyindole group. The second band group is quite complicated and is regarded as being composed of several bands. The lower energy part of the second band group is ascribed to the three orbitals relevant to the third highest occupied pi orbital of 5-methoxyindole and the highest occupied pi and the n sub C sub = sub 0 orbitals of N-ethylacetamide. The interactions among the three orbitals have been found to operate on the basis of the molecular orbital calculations; these interactions depend strongly o...

  5. Toxicity evaluation of 2-hydroxybiphenyl and other compounds involved in studies of fossil fuels biodesulphurisation.

    Science.gov (United States)

    Alves, L; Paixão, S M

    2011-10-01

    The acute toxicity of some compounds used in fossil fuels biodesulphurisation studies, on the respiration activity, was evaluated by Gordonia alkanivorans and Rhodococcus erythropolis. Moreover, the effect of 2-hydroxybiphenyl on cell growth of both strains was also determined, using batch (chronic bioassays) and continuous cultures. The IC₅₀ values obtained showed the toxicity of all the compounds tested to both strains, specially the high toxicity of 2-HBP. These results were confirmed by the chronic toxicity data. The toxicity data sets highlight for a higher sensitivity to the toxicant by the strain presenting a lower growth rate, due to a lower cells number in contact with the toxicant. Thus, microorganisms exhibiting faster generation times could be more resistant to 2-HBP accumulation during a BDS process. The physiological response of both strains to 2-HBP pulse in a steady-state continuous culture shows their potential to be used in a future fossil fuel BDS process. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Gravity-driven convection studies in compound semiconductor crystal growth by physical vapor transport

    Science.gov (United States)

    Zoutendyk, J. A.; Akutagawa, W. M.

    1982-01-01

    Experimental results are summarized, and it is pointed out that gravity-driven convection can alter the diffusive-advective mass transport behavior in the growth of crystals by physical vapor transport. Specially designed and constructed transparent furnaces are described which are being used to study the effects of gravity in the crystal growth of the compound semiconductors PbTe and CdTe. The theory underlying vapor transport behavior is reviewed, with attention given to the vapor-solid behavior of compound materials, to one-dimensional mass transport, and to gravity-induced (natural) convection. In the transparent furnaces, the quartz capillary tube mounted along the axis of the main quartz ampoule is used to measure the temperature at the growth surface (vapor-solid crystal interface) and the source, as well as the complete temperature profile along the axis of the tube. The light-pipe works to remove heat from the growth end of the ampoule by radiative heat transfer. The ampoules are sealed after being evacuated to the low 10 to the -8th torr range with a cryogenic vacuum pump.

  7. Study of Recycled and Virgin Compounded Metal Injection Moulded Feedstock for Stainless Steel 630

    Science.gov (United States)

    Manonukul, Anchalee; Likityingwara, Warakij; Rungkiatnawin, Phataraporn; Muenya, Nattapol; Amoranan, Suttha; Kittinantapol, Witoo; Surapunt, Suphachai

    Fine rounded powders preferable for metal injection moulding (MIM) are expensive. This forces MIM makers to recycle green scraps, for example, the runner system and defected green parts. This is particularly necessary for injection moulded small parts where parts are only a small portion of the injection short size. There is very little published data, although recycling feedstock has been practise throughout the industry. This work aims at investigating the effects of recycled stainless steel 630 feedstock content on the density, mechanical properties, dimensional changes and microstructure. Five batches of compounded virgin and recycled feedstock were studies from 0% to 100% recycled feedstock with the increment of 25%. Homogenously compounded feedstock was injected using the same injection condition. Subsequently, green parts were debinded and sintered at 1325°C for 2 hours in argon atmosphere. The results suggest that the green density increases linearly with increasing percentage of recycled feedstock because the polymeric binder was broken down during previous process. However, the sintered density remains nominally constant. As a result, the mechanical properties and microstructure of sintered parts are independent of recycled feedstock content. However, the volumetric and linear shrinkage decreases linearly with the increase in percentage of recycled feedstock. The difference in shrinkage is vital to dimensional control during commercial production. For example, only 4.5% of recycled feedstock can be added to virgin feedstock if a tolerance of ±0.3 mm is required for a 25 mm MIM part.

  8. Cysticidal activity of extracts and isolated compounds from Teloxys graveolens: In vitro and in vivo studies.

    Science.gov (United States)

    Palomares-Alonso, Francisca; Rojas-Tomé, Irma Susana; Juárez Rocha, Victorino; Palencia Hernández, Guadalupe; González-Maciel, Angélica; Ramos-Morales, Andrea; Santiago-Reyes, Rosalba; González-Hernández, Iliana Elvira; Jung-Cook, Helgi

    2015-09-01

    In the search of new alternatives for neurocysticercosis treatment, the cysticidal activity of organic extracts of Teloxys graveolens was evaluated. The in vitro activity of hexane, ethyl acetate and methanol extracts against Taenia crassiceps cysts was tested and the selectivity index relative to human fibroblasts was determined. Subsequently, the in vivo efficacy of the methanolic extract at doses of 200 and 500 mg/kg in the murine cysticercosis model was evaluated. The ultrastructural effects in vitro and in vivo of the methanolic extract were also investigated using scanning electron microscopy. Additionally, a bioassay-guided fractionation for the isolation of the cysticidal components was performed. Our in vitro findings revealed that all extracts exhibited good cysticidal activity with EC50 values from 44.8 to 67.1 µg/mL. Although the ethyl acetate and methanolic extracts displayed low cytotoxicity, the methanolic extract was the most selective. The methanolic extract also showed in vivo efficacy which was similar to that obtained with ABZ. Significant alterations were found on the germinal layer of the cysts, with a high accumulation of granules of glycogen and vacuoles. The bioguided fractionation of methanolic extract led to the isolation of three flavonoids: chrysin, pinocembrin and pinostrobin; among them, pinocembrin was the compound that displayed cysticidal activity. This is the first study which reveals that T. graveolens could be a potential source for cysticidal and non-toxic compounds. Published by Elsevier Inc.

  9. Electronic structures of melatonin and related compounds studied by photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, Mari. E-mail: marik@hc.cc.keio.ac.jp; Kobayashi, Tsunetoshi

    2003-02-01

    Melatonin is a hormone structurally regarded as being composed of a 5-methoxyindole group and an N-ethylacetamide group; its various physiological activities have attracted a great deal of attention recently. The gas phase He(I) photoelectron spectra of melatonin (M) and its related compounds including N-acetylserotonin have been studied with the aid of molecular orbital calculations. The first photoelectron spectral band group of compound M is ascribed to ionizations from the two {pi} orbitals localized on the methoxyindole group. The second band group is quite complicated and is regarded as being composed of several bands. The lower energy part of the second band group is ascribed to the three orbitals relevant to the third highest occupied {pi} orbital of 5-methoxyindole and the highest occupied {pi} and the n{sub C=0} orbitals of N-ethylacetamide. The interactions among the three orbitals have been found to operate on the basis of the molecular orbital calculations; these interactions depend strongly on the conformations. The high energy end of the second band group is relevant to the {pi} orbital mainly localized on the 5-methoxyindole group and is ascribed to the fourth highest occupied {pi} orbital of 5-methoxyindole.

  10. A first principle study of band structure of III-nitride compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Rashid [Centre for High Energy Physics University of the Punjab, Lahore-54590 (Pakistan)]. E-mail: rasofi@hotmail.com; Akbarzadeh, H. [Department of Physics, Isfahan University of Technology, 841546 Isfahan (Iran, Islamic Republic of); Fazal-e-Aleem [Centre for High Energy Physics University of the Punjab, Lahore-54590 (Pakistan)

    2005-12-15

    The band structure of both phases, zinc-blende and wurtzite, of aluminum nitride, indium nitride and gallium nitride has been studied using computational methods. The study has been done using first principle full-potential linearized augmented plane wave (FP-LAPW) method, within the framework of density functional theory (DFT). For the exchange correlation potential, generalized gradient approximation (GGA) and an alternative form of GGA proposed by Engel and Vosko (GGA-EV) have been used. Results obtained for band structure of these compounds have been compared with experimental results as well as other first principle computations. Our results show a significant improvement over other theoretical work and are closer to the experimental data.

  11. QSAR based docking studies of marine algal anticancer compounds as inhibitors of protein kinase B (PKBβ).

    Science.gov (United States)

    Davis, G Dicky John; Vasanthi, A Hannah Rachel

    2015-08-30

    Marine algae are prolific source of bioactive secondary metabolites and are found to be active against different cancer cell lines. QSAR studies will explicate the significance of a particular class of descriptor in eliciting anticancer activity against a cancer type. Marine algal compounds showing anticancer activity against six different cancer cell lines namely MCF-7, A431, HeLa, HT-29, P388 and A549 taken from Seaweed metabolite database were subjected to comprehensive QSAR modeling studies. A hybrid-GA (genetic algorithm) optimization technique for descriptor space reduction and multiple linear regression analysis (MLR) approach was used as fitness functions. Cell lines HeLa and MCF-7 showed good statistical quality (R(2)∼0.75, Q(2)∼0.65) followed by A431, HT29 and P388 cell lines with reasonable statistical values (R(2)∼0.70, Q(2)∼0.60). The models developed were interpretable, with good statistical and predictive significance. Molecular descriptor analyses revealed that Baumann's alignment-independent topological descriptors had a major role in variation of activity along with other descriptors. Incidentally, earlier QSAR analysis on a variety of chemically diverse PKBα inhibitors revealed Baumann's alignment-independent topological descriptors that differentiated the molecules binding to Protein kinase B (PKBα) kinase or PH domain, hence a docking study of two crystal structures of PKBβ was performed for identification of novel ATP-competitive inhibitors of PKBβ. Five compounds had a good docking score and Callophycin A showed better ligand efficiency than other PKBβ inhibitors. Furthermore in silico pharmacokinetic and toxicity studies also showed that Callophycin A had a high drug score (0.85) compared to the other inhibitors. These results encourages discovering novel inhibitors for cancer therapeutic targets by screening metabolites from marine algae.

  12. QSRR Study of GC Retention Indices of Volatile Compounds Emitted from Mosla chinensis Maxim by Multiple Linear Regression%QSRR Study of GC Retention Indices of Volatile Compounds Emitted from Mosla chinensis Maxim by Multiple Linear Regression

    Institute of Scientific and Technical Information of China (English)

    曹慧; 李祖光; 陈小珍

    2011-01-01

    The volatile compounds emitted from Mosla chinensis Maxim were analyzed by headspace solid-phase micro- extraction (HS-SPME) and headspace liquid-phase microextraction (HS-LPME) combined with gas chromatography-mass spectrometry (GC-MS). The main volatiles from Mosla chinensis Maxim were studied in this paper. It can be seen that 61 compounds were separated and identified. Forty-nine volatile compounds were identified by SPME method, mainly including myrcene, a-terpinene, p-cymene, (E)-ocimene, thymol, thymol acetate and (E)-fl-farnesene. Forty-five major volatile compounds were identified by LPME method, including a-thujene, a-pinene, camphene, butanoic acid, 2-methylpropyl ester, myrcene, butanoic acid, butyl ester, a-terpinene, p-cymene, (E)-ocimene, butane, 1,1-dibutoxy-, thymol, thymol acetate and (E)-fl-farnesene. After analyzing the volatile compounds, multiple linear regression (MLR) method was used for building the regression model. Then the quantitative structure-retention relationship (QSRR) model was validated by predictive-ability test. The prediction results were in good agreement with the experimental values. The results demonstrated that headspace SPME-GC-MS and LPME-GC-MS are the simple, rapid and easy sample enrichment technique suitable for analysis of volatile compounds. This investigation provided an effective method for predicting the retention indices of new compounds even in the absence of the standard candidates.

  13. 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.

  14. Study on Antibacterial Effect of Medlar and Hawthorn Compound Extract In Vitro

    OpenAIRE

    Niu, Yang; Nan, Yi; Yuan, Ling; Wang, Rong

    2013-01-01

    This paper evaluated the antibacterial effect of medlar and hawthorn compound extract in vitro. Water extract method and ethanol extraction method was adopted to prepare the compound extracts, and disc diffusion method and improved test tube doubling dilution method were used to conduct the antibacterial test on the two common pathogenic bacteria, Staphylococcus aureus and Klebsiella pneumonia, in vitro. The results showed that medlar and hawthorn compound extract was moderately sensitive to ...

  15. Study on Antibacterial Effect of Medlar and Hawthorn Compound Extract In Vitro

    OpenAIRE

    Niu, Yang; Nan, Yi; Yuan, Ling; Wang, Rong

    2013-01-01

    This paper evaluated the antibacterial effect of medlar and hawthorn compound extract in vitro. Water extract method and ethanol extraction method was adopted to prepare the compound extracts, and disc diffusion method and improved test tube doubling dilution method were used to conduct the antibacterial test on the two common pathogenic bacteria, Staphylococcus aureus and Klebsiella pneumonia, in vitro. The results showed that medlar and hawthorn compound extract was moderately sensitive to ...

  16. Theoretical studies on new potential high energy density compounds (HEDCs) adamantyl nitrates from gas to solid

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A series of adamantyl nitrates have been theoretically studied from gas to solid to search for new po-tential high energy density compounds (HEDCs). The heats of formation (HOFs) for the 26 title com-pounds were calculated by designing isodesmic reactions at the B3LYP/6-31G level. It was found that the HOFs of the 26 isomers with the same number of —ONO2 groups (n) are not correlated well with the corresponding substituted positions. According to the obtained heats of detonation (Q),detonation velocities (D),and detonation pressures (P) using the Kamlet-Jacobs equations,it was found that when n=7~8,the adamantyl nitrates meet the criterion as an HEDC. The calculations on bond dissociation energies of O—N (EO—N) showed that the adamantyl nitrates with gemi —ONO2 always have the worst stability among the isomers,and all the adamantyl nitrates with gemi —ONO2 have similar stability. Due to the complexity of their structures,values of EO—N do not decrease with the increase of the substituent number n obviously,and the stability of adamantyl nitrates is not determined by only one structural parameter. Considering the stability requirement,only 1,2,4,6,8,9,10-adamantyl heptanitrate is recom-mended as a feasible HEDC. Molecular packing searching for 1,2,4,6,8,9,10-adamantyl heptanitrate among 7 most possible space groups (P21/c,P-1,P212121,P21,Pbca,C2/c,and Pna21) using Compass and Dreiding force fields showed that this compound tends to crystallize in P21/c. Ab initio periodic calculations on the electronic structure of the predicted packing showed that the O—NO2 bond is the trigger bond during thermolysis,which agrees with the result derived from the study of dissociation energies of O—N bonds.

  17. Pittsburgh compound B imaging and cerebrospinal fluid amyloid-β in a multicentre European memory clinic study

    DEFF Research Database (Denmark)

    Leuzy, Antoine; Chiotis, Konstantinos; Hasselbalch, Steen G

    2016-01-01

    observed for cognitively normal and non-Alzheimer's disease groups. Agreement between Pittsburgh compound B classification and Meso Scale Discovery/mass spectrometry reference measurement procedure findings was further improved when using amyloid-β42/40 Agreement between Pittsburgh compound B visual...... ratings and Centiloids was near complete. Despite improved agreement between Pittsburgh compound B and centrally analysed cerebrospinal fluid, a minority of subjects showed discordant findings. While future studies are needed, our results suggest that amyloid biomarker results may not be interchangeable...

  18. High-pressure study of the new Y-Ba-Cu-O superconducting compound system

    Science.gov (United States)

    Hor, P. H.; Gao, L.; Meng, R. L.; Huang, Z. J.; Wang, Y. Q.

    1987-01-01

    Hydrostatic effects on the superconducting transition temperature of the Y-Ba-Cu-O compound system, resistively, up to 19 kbar are investigated. It is found that pressure has little effect on the superconducting state of Y-Ba-Cu-O, in marked contrast to the behavior of the K2NiF4-phase La-Ba-Cu-O and La-Sr-Cu-O systems. It is suggested that this effect may be due to chemical pressure associated with the smaller Y atoms already present in Y-Ba-Cu-O. X-ray powder-diffraction studies show that the high-temperature superconductivity in Y-Ba-Cu-O can only be attributed to one or more phases with structures different from the cubic perovskite or tetragonal layered ones.

  19. Ammonia as a case study for the spontaneous ionization of a simple hydrogen-bonded compound.

    Science.gov (United States)

    Palasyuk, Taras; Troyan, Ivan; Eremets, Mikhail; Drozd, Vadym; Medvedev, Sergey; Zaleski-Ejgierd, Patryk; Magos-Palasyuk, Ewelina; Wang, Hongbo; Bonev, Stanimir A; Dudenko, Dmytro; Naumov, Pavel

    2014-03-24

    Modern ab initio calculations predict ionic and superionic states in highly compressed water and ammonia. The prediction apparently contradicts state-of-the-art experimentally established phase diagrams overwhelmingly dominated by molecular phases. Here we present experimental evidence that the threshold pressure of ~120 GPa induces in molecular ammonia the process of autoionization to yet experimentally unknown ionic compound--ammonium amide. Our supplementary theoretical simulations provide valuable insight into the mechanism of autoionization showing no hydrogen bond symmetrization along the transformation path, a remarkably small energy barrier between competing phases and the impact of structural rearrangement contribution on the overall conversion rate. This discovery is bridging theory and experiment thus opening new possibilities for studying molecular interactions in hydrogen-bonded systems. Experimental knowledge on this novel ionic phase of ammonia also provides strong motivation for reconsideration of the theory of molecular ice layers formation and dynamics in giant gas planets.

  20. Study of Effective Atomic Number in Compounds Using Gamma-Ray Interaction

    Science.gov (United States)

    Rudraswamy, B.; Dhananjaya, N.

    2009-03-01

    In view of low cost, hydrogenous materials such as Polyethylene and CH2 have been developed and being used currently by NASA as an effective galactic cosmic radiation shields in place of aluminum for hull design of spacecraft. Lead, steel and concrete which are currently being used as effective radiation shields for the treatment of rooms equipped with Electron accelerators are found be quite expensive. Hence, it is necessary to use alternative low cost material which serves as an effective radiation shield. In the present study, an attempt has been made to measure gamma-ray mass attenuation coefficient, effective atomic number and absorbed dose rate of the compounds such as NH4Cl, KCl, and CdO using various gamma sources of energies 356, 511, 662, 1173, and 1332 keV. These parameters are expected to gives vital information on the selection of shielding materials.

  1. [Preliminary study concerning emissions of the volatile organic compounds from cooking oils].

    Science.gov (United States)

    He, Wan-Qing; Tian, Gang; Nie, Lei; Qu, Song; Li, Jing; Wang, Min-Yan

    2012-09-01

    Cooking oil fume is one of the important sources of atmospheric volatile organic compounds (VOCs), which are the key precursors of ozone and secondary organic aerosols in air. In this study, the production of cooking oil fume was simulated by heating typical pure vegetable oils (peanut oil, sunflower oil, soybean oil, olive oil and blend oil) at different temperatures in beakers to investigate the VOCs emission characteristics. The emitted VOCs were sampled with a Tenax adsorption tube and analyzed using GC-MS after thermal desorption. The results showed that the emission of VOCs increased with the increase of the heating temperature for all the investigated cooking oils, and at a given temperature, the blend oil emitted the lowest amount of VOCs. The VOCs emission intensity at different heating temperatures fitted well with binomial equations and ranged from 1.6-11.1 mg x (kg x min)(-1).

  2. A study on compound contents for plastic injection molding products of metallic resin pigment

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Whan; Kwak, Jae Seob [Dept. of Mechanical Engineering, Pukyong National University, Busan (Korea, Republic of); Lee, Gyu Sang [Alliance Molding Engineering TeamLG Electronics Inc., Osan (Korea, Republic of)

    2016-12-15

    Injection molding process is widely used for producing most plastic products. In order to make a metal-colored plastic product especially in modern luxury home alliances, metallic pigments which are mixed to a basic resin material for injection molding are available. However, the process control for the metal-colored plastic product is extremely difficult due to non-uniform melt flow of the metallic resin pigments. To improve the process efficiency, a rapid mold cooling method by a compressed cryogenic fluid and electricity mold are also proposed to decrease undesired compound contents within a molded plastic product. In this study, a quality of the metal-colored plastic product is evaluated with process parameters; injection speed, injection pressure, and pigment contents, and an influence of the rapid cooling and heating system is demonstrated.

  3. Formation, characterization and computational studies of mono- and dinuclear rhenium(I) chromone compounds

    Science.gov (United States)

    Ebinumoliseh, Ifeoma; Booysen, Irvin Noel; Akerman, Matthew Piers; Xulu, Bheki

    2016-11-01

    Herein, we report the formation and characterization of a novel dinuclear rhenium(I) compound, fac-(Re(CO)3Br)2(μ-chret) (1) [chret = N, N'-bis(2-amino-3-imino)methylenechromone-1,2-ethane] and a mononuclear metal complex, fac-[Re(CO)3(bzch)Br] (2) [bzch = 2-benzimidazole-4H-chromen-4-one]. The metal complexes were characterized by 1H NMR-, IR-, UV-Vis, melting point and conductivity measurements. The solid-state structures for 1 and 2 were confirmed via single crystal X-ray analysis. X-ray studies of 2 revealed the transformation of the chb diimine into the bzch chelator (in 2). The simulated IR spectra for the respective metal complexes provided insight in the interpretation of their corresponding experimental spectra.

  4. 31P NMR Studies on the Ligand Dissociation of Trinuclear Molybde-num Cluster Compounds

    Institute of Scientific and Technical Information of China (English)

    李兆基; 覃业燕; 姚元根; 唐艳红; 康遥; 夏继波; 陈忠; 吴棱

    2003-01-01

    A series of carboxylate-substituted trinudear molybdenum dus-ter compounds formulated as Mo3S4(DTP)3(RCO2)(L), where RffiH, CH3, C2H5, CH2Cl, CCl3, R1C6H4(R1 is the group on the benzene ring of aromatic carboxylate ), L=pyridine,CH3CN, DMF, have been synthesized by the ligand substitu-tion reaction. The dissociation of the loosely-coordinated ligand L from the cluster core was studied by 31p NMR. The dissocia-tion process of L is related to the solvent, temperature, and acidity of carboxylate groups, so as to affect the solution struc-ture and reactive properties of the duster. The long-distance in-teraction between ligands RCO2 and L is transported by Mo3S4 core.

  5. NMR studies in the half-Heusler type compound YbPtSb

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, T; Abe, M; Mito, T; Ueda, K; Kohara, T [Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan); Suzuki, H S, E-mail: t-koyama@sci.u-hyogo.ac.jp [National Institute for Materials Science, Tsukuba 305-0047 (Japan)

    2011-01-01

    {sup 121}Sb and {sup 19B}Pt nuclear magnetic resonance (NMR) has been studied in the half-Heusler type compound YbPtSb to obtain information on local magnetic behavior. The characteristics of the localized 4f spins are observed in the Cuire-Weiss type behavior of the Knight shifts K for both {sup 121}Sb and {sup 19B}Pt. From the slope of K-{sub {chi}} plots we estimated hyperfine coupling constants of -3.8 and -4.6 kOe/{mu}{sub B} at Sb and Pt sites, respectively. It was found that the spin-echo decay rate 1/T{sub 2} of {sup 121}Sb shows a clear peaks at 10 K. Similar tendency was also observed in case of {sup 19B}Pt. However, static properties do not show any anomalies near 10 K.

  6. A study on multifunction heat pipe type high efficient adsorption refrigerator using compound adsorbent-ammonia

    Institute of Scientific and Technical Information of China (English)

    LU Zisheng; WANG Ruzhu; WANG Liwei; CHEN Chuanjuan

    2006-01-01

    A multifunction heat pipe adsorption refrigerator is designed, which uses solidified compound adsorbent of CaCl2 and activated carbon as adsorbent. Two work conditions, ice-maker driven by the exhaust heat from diesel engine and air-condi- tioning powered by solar energy, are studied. SCP (specific cooling power) and COP (coefficient of per- formance) for different conditions are analyzed. The optimum average SCP and COP for the refrigerator powered by waste heat of diesel engine are 770.4 W/kg and 0.39 at about -20℃ evaporating tem- perature. The optimum average SCP and COP for the refrigerator powered by solar energy are 524.2 W/kg and 0.27 at about 5.6℃ evaporating tempera- ture.

  7. 3D-QSAR study on phenoxy-alkylamine compounds of a 1-adrenoceptor antagonist

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The study of three-dimensional quantitative structure-activityrelationship (3D-QSAR) of DDPH and its derivatives that have been known with their activity parameters has been developed using the comparative molecular field analysis (CoMFA) method. Here, (+)-DDPH crystal structure was selected as the active conformation model and comparisons between the influences of different charge calculation methods and grid setup were conducted. The coefficients of cross-validation (q2 ) and regression (r2) are 0.481 and 0.997, respectively. The standard error (SE) is 0.102. The research result suggests that the steric field makes more contributions to the activity than the electrostatic field. This model can help us not only in improving our understanding of the receptor-ligand interactions, but also in predicting the activity of derivatives and designing new compounds with better potency.

  8. Structural and property studies on metal-organic compounds with 3-D supramolecular network

    Science.gov (United States)

    Zhang, Qi-Ying; Ma, Ke-Fang; Xiao, Hong-Ping; Li, Xin-Hua; Shi, Qian

    2014-07-01

    Two carboxylato-bridged allomeric compounds, {[Cu2(dbsa)2(hmt) (H2O)4]1/2·2H2O}n (1), {[Ni(dbsa)(H2O)2]1/2[Ni(dbsa)(hmt)(H2O)2]1/2·2H2O}n (2) (H2dbsa=meso-2,3-dibromosuccinic acid, hmt=hexamethylenetetramine) have been synthesized and characterized by X-ray structral analyses. The metal ions have two kinds of coordination fashion in one unit, and bridged by carboxylate and hmt ligands along with weak interactions existing in the solid structure, forming a 3-D supramolecular network. Variable-temperature magnetic property studies reveal the existence of antiferromagnetic interactions in 1 and 2 with g=2.2, J1=-3.5 cm-1, J2=-2.8 cm-1 for 1, and g=2.1, J=-3.5 cm-1 for 2.

  9. Study on antibacterial effect of medlar and hawthorn compound extract in vitro.

    Science.gov (United States)

    Niu, Yang; Nan, Yi; Yuan, Ling; Wang, Rong

    2013-01-01

    This paper evaluated the antibacterial effect of medlar and hawthorn compound extract in vitro. Water extract method and ethanol extraction method was adopted to prepare the compound extracts, and disc diffusion method and improved test tube doubling dilution method were used to conduct the antibacterial test on the two common pathogenic bacteria, Staphylococcus aureus and Klebsiella pneumonia, in vitro. The results showed that medlar and hawthorn compound extract was moderately sensitive to Staphylococcus aureus, while its inhibiting effect on Klebsiella pneumoniae was particularly significant, moreover, the antibacterial effect of ethanol extract was better than water extract. Medlar and hawthorn compounds had good antibacterial effect on the two pathogenic bacteria.

  10. Surface interactions of aromatic organoarsenical compounds with hematite nanoparticles using ATR-FTIR: kinetic studies.

    Science.gov (United States)

    Arts, Derek; Abdus Sabur, Md; Al-Abadleh, Hind A

    2013-03-14

    Aromatic organoarsenicals p-arsanilic acid (pAsA) and roxarsone (ROX) are used as feed additives in developing countries that allow the use of arsenic-containing compounds in their poultry industry. These compounds are introduced to the environment through the application of contaminated poultry litter. Little is known about the surface chemistry of these organoarsenicals on the molecular level with reactive components in soils. We report herein the first in situ and surface-sensitive rapid kinetic studies on the adsorption and desorption of pAsA to/from hematite nanoparticles at pH 7 using ATR-FTIR. Values for the apparent initial rates of adsorption and desorption were extracted from experimental data as a function of spectral components. Hydrogen phosphate was used as a desorbing agent due to its ubiquitous presence in litter, and its adsorption kinetics was investigated on surfaces with and without surface arsenic. Initial first-order pseudo-adsorption rate constant for pAsA was lower by a factor of 1.6 than that of iAs(V), suggesting an average behavior for the formation of quantitatively more weakly bonded monodentate or hydrogen-bonded complexes for the former relative to strongly bonded bidentate surface complexes for the latter under our experimental conditions. Initial first-order pseudo-adsorption rate constants for hydrogen phosphate decrease in this order: fresh hematite > pAsA/hematite ≈ phenylarsonic acid (PhAs)/hematite > iAs/hematite by factors 1.5 and 3 relative to fresh films, respectively. Initial desorption kinetics of aromatic organoarsenicals due to flowing hydrogen phosphate proceed with a nonunity overall order, suggesting a complex mechanism, which is consistent with the existence of more than one type of surface complexes. The impact of our studies on the environmental fate and transport of aromatic organoarsenicals in geochemical environments and their overall surface chemistry with iron (oxyhyr)oxides is discussed.

  11. Mefloquine, a new type of compound against schistosomes and other helminthes in experimental studies.

    Science.gov (United States)

    Xiao, Shu-hua

    2013-11-01

    Up to date, schistosomiasis is still prevalent worldwide. It is estimated that more than 200 million individuals are infected, and 120 million suffer from clinical morbidity. Facing such huge cases of schistosomiasis, only heavy reliance on a single praziquantel for schistosomiasis control does not adapt and may promote the selection and spread of drug-resistant parasites. Therefore, it is an urgent need to develop the new antischistosomal drug. In 2008-2009, the antimalarial drug mefloquine, an arylaminoalcohol compound, has been found to be effective against schistosomes. According to the experimental studies, the deepest impression on the antischistosomal properties of mefloquine can be summarized as following points: (1) single dose of mefloquine possesses potential effect against three major species of schistosomes (Schistosoma mansoni, Schistosoma haematobium, and Schistosoma japonicum) infecting humans; (2) the drug displays similar effects against developing stages of juvenile and adult schistosomes, which are superior to that of artemisinins and praziquantel; (3) in vitro mefloquine exerts direct killing effect on juvenile and adult schistosomes, while in vivo, the efficacy of the drug is independent to host immune response, (4) mefloquine causes extensive and severe morphological, histopathological, and ultrastructural damage to adult and juvenile schistosomes, particularly, the worm tegument, musculature, gut, and vitelline glands of female worms are the key sites attacked by the drug; (5) combined treatment with mefloquine and praziquantel, or artemisinins shows synergistic effect against schistosome in experimental therapy,while in initially clinical trial, mefloquine in combination with artesunate also exhibits higher cure rates against schistosomiasis hematobia and schistosomiasis mansoni, and (6) several mefloquine-related arylmethanols exhibit potential effect against schistosomes in vivo, which is a useful clue helpful for development of new

  12. Identification of two natural compound inhibitors of Leishmania donovani Spermidine Synthase (SpdS) through molecular docking and dynamic studies.

    Science.gov (United States)

    V M, Vidhya; Dubey, Vikash Kumar; Ponnuraj, Karthe

    2017-09-05

    Visceral leishmaniasis caused by the protozoan Leishmania donovani is the most severe form of leishmaniasis and it is potentially lethal if untreated. Despite the availability of drugs for treating the disease, the current drug regime suffers from drawbacks like antibiotic resistance and toxicity. New drugs have to be discovered in order to overcome these limitations. Our aim is to identify natural compounds from plant sources as putative inhibitors considering the occurrence of structural diversity in plant sources. Spermidine Synthase (SpdS) was chosen as the target enzyme as it plays a vital role in growth, survival, and due to its contribution in virulence. Our initial investigation started with a literature survey in identifying natural compounds that showed antileishmanial activity. Subsequently, we identified two monoterpenoid compounds, namely Geraniol and Linalool, that were structurally analogous to one of the substrates (putrescine) of SpdS. In the present study, homology model of L. donovani SpdS was generated and the binding affinity of the identified compounds was analyzed and also compared with the putrescine through molecular docking and dynamic studies. The pharmacokinetic properties of the identified compounds were validated and the binding efficiency of these ligands over the original substrate has been demonstrated. Based on these studies, Geraniol and Linalool can be considered as lead molecules for future investigations targeting SpdS. This study further emphasizes the choice of natural compounds as a good source of therapeutic agents.

  13. STUDIES ON HUMAN SPERMATOZOAL MOTILITY WITH THE USE OF THE MULTIPLE EXPOSURE PHOTOGRAPHY METHOD - EFFECTS OF VARIOUS COMPOUNDS -

    OpenAIRE

    羽間, 稔

    1982-01-01

    The effects of various compounds, such as Kallikrein, 17β-estradiol, progesterone, prolactin, L-arginine, caffeine, and Solcoseryl, on sperm motility were studied. These compounds were added to fresh human semen offered by 28 volunteers who had presented with various findings, and the percentage of motile sperm and spermatozoal velocity were evaluated by objective semen analysis with the new multiple exposure photography (MEP) method using a stroboscope for photography and a computer for data...

  14. A Comparative Study of Dihydroartemisinin Compounds in Treatment of Uncomplicated Falciparum Malaria in Kampong of Cambodia

    Institute of Scientific and Technical Information of China (English)

    SONGJian-ping; DuongSocheattffu

    2003-01-01

    Objective:To compare the safety and efficacy of two compounds of dihydroartemisinin (DHA)-Artekin and Artekin(T)in the treatement of uncomplicated falciparum malaria.Methods:The regiment of 8-tablet for 2 days of Artekin and Artekin(T) were applied to 100 patients with uncompli-cated falciparum malaria,who were radomly divided into two groups.Each group contained 50 cases.The cure rate ,the mean parasites clearance time,the mean fever clearance and side-effects were observed to assess the safety and efficacy of the compunds used.Results:The mean parasites clearance time was 31.7±9.0 hours in the Artekin group and 32.8±8.8 hours in Artekin(T) group respectively; the mean fever clearance time was 12.7±7.2 hours in Artekin group and 16.5±7.9 hours in Artekin(T) group; there were no recrudescence case in both groups within the 28 days of follow-up ,the cure rates in Artekin group and Artekin(T)groups were 100%.It indicated that the tolerability of both compunds were very good,the side-effects such as nausea,abdominal pain were mild and self-limited.Conclusion:The study preliminarily indicated that the DHA and PQ compounds were of high efficacy,rapid acting and low toxici-ty.Artekin is very promising as a cheap,simple,effective treatment for multi-resistance malaria in Cam-bodia.

  15. A quantitative study of the biotransformation of insulin-enhancing VO(2+) compounds.

    Science.gov (United States)

    Sanna, Daniele; Buglyó, Péter; Micera, Giovanni; Garribba, Eugenio

    2010-08-01

    Potentiometric (pH titrations) and spectroscopic (electron paramagnetic resonance) methods have been used to determine the thermodynamic stability constants of the various VO(2+) complexes formed after the interaction of four insulin-enhancing vanadium compounds, [VO(6-mepic)(2)], cis-[VO(pic)(2)(H(2)O)], [VO(acac)(2)], and [VO(dhp)(2)], where 6-mepic, pic, acac, and dhp indicate the deprotonated forms of 6-methylpicolinic acid, picolinic acid, acetylacetone, and 1,2-dimethyl-3-hydroxy-4(1H)-pyridinone, with high molecular mass [human serum apotransferrin (hTf) and human serum albumin (HSA)] and low molecular mass (lactate) components of blood serum. In particular, log beta values for the formation of (VO)hTf (13.0 +/- 0.5), (VO)(2)hTf (25.5 +/- 0.5), (VO)HSA (9.1 +/- 1.0), (VO) (2) (d) HSA (20.9 +/- 1.0), cis-VO(dhp)(2)(hTf) (25.5 +/- 0.6), cis-VO(dhp)(2)(HSA) (25.9 +/- 0.6), (VO)hTf(lact) (14.5 +/- 0.8), (VO)(2)hTf(lact)(2) (28.5 +/- 0.8), (VO)hTf(pic) (15.6 +/- 0.8), and (VO)(2)hTf(pic)(2) (30.4 +/- 0.8) were determined. The values of the stability constants were used to compare the calculated composition of ternary and quinary systems with that recently proposed by some of us through electron paramagnetic resonance and density functional theory methods (Sanna et al. in Inorg. Chem. 49:174-187, 2010) and to predict the distribution of VO(2+) ion in blood serum when one of the four insulin-enhancing vanadium compounds studied, [VO(carrier)(2)], is administered.

  16. Studies on the Photodynamic Mechanism of Tetrapyrrole Compounds by Laser Flash Photolysis

    Institute of Scientific and Technical Information of China (English)

    DENG,Kui; CHEN,Zhi-Long; ZHOU,Xing-Ping; WANG,Wen-Feng; YANG,Xiao-Xia; TIAN,Juan

    2008-01-01

    Photodynamic therapy (PDT) is a promising new treatment technique which can potentially destroy unwanted and malignant tissues, such as those of cancer. The photodynamic mechanisms of three tetrapyrrole compounds:Mg-purpurin-18, tetra(meso-chlorophenyl)porphyrin (m-TCPP) and 2,7,12,18-tetramethyl-3,8-di[(1-isobutoxyl)-ethyl]-13,17-bis[3-di(2-chloroethyl)aminopropyl]porphyrin (TDBP) in acetonitrile were investigated by 355 nm laser flash photolysis. It was found that after laser flash photolysis (LFP), the excited states of TDBP and Mg-purpurin-18 could react with O2 and 1O2 was produced, which proved that TDBP and Mg-purpurin-18 took effects through type Ⅱ mechanism in PDT. This suggested that TDBP and Mg-purpurin-18 should be suitable for target tissues containing enough O2. Mg-purpurin-18 has two extra absorptions at 550 and 700 nm, which means it has broad choices of laser wavelength in PDT. It was also found that m-TCPP could be photoionized when excited with 355 nm laser under N2-saturated condition. It could also react with O2 to produce reactive oxygen species such as superoxide and the peroxide anions, but not 1O2. These were known as the Type Ⅰ mechanism. So m-TCPP could be used even at low oxygen concentration or more polar environments with good behavior in PDT. From the above studies on the three different tetrapyrrole compounds it could be concluded that the structure of porphin ring takes a main role in PDT. And there was important impact on the photodynamic mechanism for the functional group directly connecting with porphin ring, while little influence for the functional group indirectly connecting with porphin ring. These will be of great value in the discovery of new PDT drugs.

  17. DFT studies of the vibrational spectra of salicylic acid and related compounds

    Science.gov (United States)

    Compounds that exhibit intra- and intermolecular hydrogen bonds can have infrared and Raman spectra that show evidences of these hydrogen bonds. In modeling the vibrational spectra of such compounds, the addition of explicit hydrogen bonding species (e.g. solvent molecules) can often improve agreeme...

  18. Study on the local atomic structure of germanium in organic germanium compounds by EXAFS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Organic germanium compounds have been extensively applied in medicine as tonics,In this paper,the local structures of two organic germanium compounds,carboxyethylgermanium sesquioxide and polymeric germanium glutamate,were determined by EXAFS.The structure parameters including coordination numbers and bond lengths were reported,and possible structure patterns were discussed.

  19. Case study: Comparison of biological active compounds in milk from organic and conventional dairy herds

    Science.gov (United States)

    Conflicting reports of the quantities of biologically active compounds present in milk from organic grass-fed and conventional herds show that more research is required, especially as these compounds are linked to human health benefits and can improve the health value consumers place on dairy produc...

  20. Predicting the reactivity of phenolic compounds with formaldehyde. II, continuation of an ab initio study.

    Science.gov (United States)

    Tohru Mitsunaga; Anthony H. Conner; Charles G. Jr. Hill

    2002-01-01

    Phenol–formaldehyde resins are important adhesives used by the forest products industry. The phenolic compounds in these resins are derived primarily from petrochemical sources. Alternate sources of phenolic compounds include tannins, lignins, biomass pyrolysis products, and coal gasification products. Because of variations in their chemical structures, the...

  1. Studies on Syntheses and Biological Activities of Novel Triazole Compounds Containing Phosphorodithioate Groups

    Institute of Scientific and Technical Information of China (English)

    XU Liang-zhong; ZHANG Shu-sheng; CHEN Xiao; JIAO Kui

    2003-01-01

    Sixteen new triazole organic phosphorus compounds were synthesized. Their structures were confirmed with IR, 1H NMR, elemental analysis and MS. The primary biological tests show that the titled compounds have the fungicidal activities, which are influenced by R groups and the substituents attached to the P atom.

  2. Studies on Synthesis and Biological Activities of Novel Triazole compounds Containing Thiophene Groups

    Institute of Scientific and Technical Information of China (English)

    XU Liang-zhong; ZHANG Shu-sheng; HU Zhi-qiang; JIAO Kui

    2003-01-01

    Fifteen new triazole compounds containing thiophene groups were synthesized and their structures were confirmed by means of 1H NMR, IR, MS spectroscopies and elemental analyses. The preliminary biological tests show that the titled compounds exhibit some activities of fungicides and plant growth regulators.

  3. Comparative Study on the Structures of Chinese and Korean Compound Words

    Directory of Open Access Journals (Sweden)

    Zhai Xun

    2016-05-01

    Full Text Available The goal of the research was to compare the compound words in Chinese, an isolated language, and Korean, an agglutinative language. This research used library research. The researchers found that the main characteristics of the formation of Korean compound words were that the latter element was the central word. The method of word formation decided its lexical category. Moreover, most of the internal relationships of the compound words were connection and modification. While in Chinese, the endocentric compound noun decided the part of speech of the compound word, and could be the proceeding element or the latter element. Furthermore, Chinese contained no complicated morphological changes. It is concluded that Korean is a Subject–Object–Verb (SOV language, where verb elements demonstrate a central feature of the compound verb are always a trailing part. Thus, there is no exocentric compound verb in Korean. By contrast, Chinese is a typical SVO language. When constituting the compound verbs, nouns or adjectives can function as the structural elements. Therefore, there is no permanent position for head words.

  4. 汉语复合词的中心性问题%A Study on Headedness of Chinese Compound Words

    Institute of Scientific and Technical Information of China (English)

    顾介鑫

    2011-01-01

    In the classical linguistic theory,it has been believed that Chinese compound word has its head;whereas in some corpus study,it was proposed that Chinese compound word is headless.In present study,the question whether Chinese compound word has its head was answered from the definition of compound word headedness,the way how to find the head,and the factors contributing to the identification of the head.It was concluded that headedness hypothesis is appropriate for Chinese compound word.Furthermore,it is more important to study the neural basis for headedness of Chinese compound word in future.%理论语言学研究认为汉语复合词是有中心的,但有学者基于语料库分析提出了相反的观点。本研究从复合词中心性的定义、中心的确定方法及制约因素三个方面,探讨汉语复合词有无中心这一问题,认为复合词中心性理论适用于汉语复合词;并进一步指出,可从神经基础的角度来深入探讨复合词的中心性问题。

  5. A UV resonance Raman (UVRR) spectroscopic study on the extractable compounds of Scots pine ( Pinus sylvestris) wood . Part I: Lipophilic compounds

    Science.gov (United States)

    Nuopponen, M.; Willför, S.; Jääskeläinen, A.-S.; Sundberg, A.; Vuorinen, T.

    2004-11-01

    The wood resin in Scots pine ( Pinus sylvestris) stemwood and branch wood were studied using UV resonance Raman (UVRR) spectroscopy. UVRR spectra of the sapwood and heartwood hexane extracts, solid wood samples and model compounds (six resin acids, three fatty acids, a fatty acid ester, sitosterol and sitosterol acetate) were collected using excitation wavelengths of 229, 244 and 257 nm. In addition, visible Raman spectra of the fatty and resin acids were recorded. Resin compositions of heartwood and sapwood hexane extracts were determined using gas chromatography. Raman signals of both conjugated and isolated double bonds of all the model compounds were resonance enhanced by UV excitation. The oleophilic structures showed strong bands in the region of 1660-1630 cm -1. Distinct structures were enhanced depending on the excitation wavelength. The UVRR spectra of the hexane extracts showed characteristic bands for resin and fatty acids. It was possible to identify certain resin acids from the spectra. UV Raman spectra collected from the solid wood samples containing wood resin showed a band at ˜1650 cm -1 due to unsaturated resin components. The Raman signals from extractives in the resin rich branch wood sample gave even more strongly enhanced signals than the aromatic lignin.

  6. Characterization of Cystic Breast Masses on Ultrasound: Comparative Study among Conventional, Tissue Harmonic, Compound, and a Combination of Tissue Harmonic and Compound Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Ji Yung; Seo, Bo Kyoung; Yi, Ann; Cho, Kyu Ran; Son, Gil Soo; Kim, Baek Hyun [Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of); Kim, Hee Young [Institute of Economics, Korea University, Seoul (Korea, Republic of); Woo, Ok Hee [Korea University Guro Hospital, Korea University College of Medicine, Seoul (Korea, Republic of)

    2010-12-15

    This prospective study was to compare the image quality and diagnostic performance of breast cystic masses by conventional and advanced ultrasound (US) techniques including tissue harmonic, compound, and the combination of these techniques. All 91 patients, collectively having 109 breast cystic masses were scanned using four US techniques (complicated cysts in 36, septated cysts in 33, and complex cysts in 40). Two breast radiologists independently assessed the image quality and possibility of malignancy. Image quality was evaluated in terms of contrast and clarity of the wall and internal echo pattern and then graded on a scale of 1 (poor) to grade 3 (satisfactory). The possibility of malignancy was graded on a scale of 1 (suggestive of benignancy) to 5 (suggestive of malignancy) using US images. The histopathological results and follow-up images were used as the reference standard for the assessment of diagnostic performance. Results were evaluated by Friedman's test and receiver operating characteristic (ROC) analyses. In terms of image quality, a grade of 3 was significantly more frequent in the three advanced US techniques than conventional US (p < 0.05). For assessment of diagnostic performance, areas under the ROC curves in three advanced techniques were significantly higher than in conventional US (p < 0.05). Advanced US techniques including compound and tissue harmonic US techniques provide a better image quality in breast cystic masses and also improve the diagnostic performance compared with conventional US

  7. 2D-QSAR Studies on Triazolone Compounds Containing Benzenesulfonic Amide

    Institute of Scientific and Technical Information of China (English)

    WEI Qing-Li; GAO Jun; SUN Dao-Xing; ZHANG Shu-Sheng

    2007-01-01

    The geometry structures of 6 triazolone compounds containing benzenesulfonic amide were fully optimized with DFT (Density Functional Theory) method at the B3LYP/6-31G level, and the structural and electronic parameters of the compounds were calculated. The hydrophobic and topological parameters of the title compounds were calculated by HyperChem software. The mono- and bi-parametric models between the parameters and biological activity of the compounds were analyzed by Multiple Linear Regression method based on Hansch-Fujita model. The results show that the activities of the title compounds were increased with higher hydrophobic property logP and molecular volume V, lower molecular energy ETOTAL and electronegative of benzene ring Qph.

  8. Theoretical study of B2 type technetium AB (A=Tc, B=Ti, V, Nb and Ta) intermetallic compounds

    Science.gov (United States)

    Acharya, Nikita; Fatima, Bushra; Sanyal, Sankar P.

    2016-12-01

    The structural, electronic, elastic and thermal properties of the cubic AB type (A=Tc, B=Ti, V, Nb and Ta) technetium intermetallic compounds have been studied using the full potential linearized augmented plane wave (FP-LAPW) method within the generalized gradient approximation (GGA) and local density approximation (LDA) used for the exchange-correlation potential. The calculated lattice parameters agree well with the experimental results. The calculated electronic properties reveal that these compounds are metallic in nature with partial ionic bonding. The elastic constants obey the stability criteria for cubic system. Ductility for these compounds has been analyzed using the Pugh's rule and Cauchy's pressure revealing ductile in nature of all the compounds. Bonding nature is discussed using Fermi surface, band structure and charge density difference plots.

  9. Docking Studies in Target Proteins Involved in Antibacterial Action Mechanisms: Extending the Knowledge on Standard Antibiotics to Antimicrobial Mushroom Compounds

    Directory of Open Access Journals (Sweden)

    Maria José Alves

    2014-01-01

    Full Text Available In the present work, the knowledge on target proteins of standard antibiotics was extended to antimicrobial mushroom compounds. Docking studies were performed for 34 compounds in order to evaluate their affinity to bacterial proteins that are known targets for some antibiotics with different mechanism of action: inhibitors of cell wall synthesis, inhibitors of protein synthesis, inhibitors of nucleic acids synthesis and antimetabolites. After validation of the molecular docking approach, virtual screening of all the compounds was performed against penicillin binding protein 1a (PBP1a, alanine racemase (Alr, d-alanyl-d-alanine synthetase (Ddl, isoleucyl-tRNA sinthetase (IARS, DNA gyrase subunit B, topoisomerase IV (TopoIV, dihydropteroate synthetase (DHPS and dihydrofolate reductase (DHFR using AutoDock4. Overall, it seems that for the selected mushroom compounds (namely, enokipodins, ganomycins and austrocortiluteins the main mechanism of the action is the inhibition of cell wall synthesis, being Alr and Ddl probable protein targets.

  10. Study of structural, electronic and elastic properties of RPd{sub 3} (R = Lu and Sc) compounds

    Energy Technology Data Exchange (ETDEWEB)

    Thakur, Veena, E-mail: gita-pagare@yahoo.co.in; Pagare, Gitanjali, E-mail: gita-pagare@yahoo.co.in; Chouhan, S. S., E-mail: gita-pagare@yahoo.co.in [Department of Physics, Government M. L. B. Girls P. G. Autonomous College, Bhopal-462002 (India); Sanyal, S. P. [Department of Physics, Barkatullah University, Bhopal-462026 (India)

    2014-04-24

    The structural, electronic and elastic properties of nonmagnetic RPd{sub 3} (R = Lu and Sc) compounds, which crystallize in AuCu{sub 3}-type structure, are studied using first principles density functional theory based on full potential linearized augmented plane wave (FP-LAPW) method. The calculations are carried out within the PBE-GGA and WC-GGA for the exchange correlation potential. Our calculated ground state properties such as lattice constant (a0), bulk modulus (B) and its pressure derivative (B’) are in good agreement with the experimental results. We first time predict the elastic constants for these compounds using different approximations of GGA. These RPd{sup 3} compounds are found to be ductile in nature in accordance with Pugh’s criteria. The computed electronic band structures and density of states show metallic character of these compounds.

  11. Molecular Docking Study of Bioactive Compound of Andrographolide against Ebola Virus

    Directory of Open Access Journals (Sweden)

    R.Sharmila

    2016-05-01

    Full Text Available Ebola virus is a single-stranded, negative-sense RNA virus that causes severe hemorrhagic fever in humans and nonhuman primates. This virus is resistance to many antibiotics also there is no proper treatment for EBOLA viral infection. In worldwide,thus many people affected by this virus and there is no drug available for treatment of Ebola virus infection. Therefore new drugs are need for therapy and prevention for this life threatening infection. Hence the current study deals with the evaluation of the potent bioactive compound Andrographolide against the three receptors of Ebola virus receptor proteins. The protein receptors VP40, VP35 and VP24 were docked with the Andrographolide and evaluated on the basis of total energy and binding affinity scores byAutoDock. Andrographolide showed a high docking score against the VP40, VP35 and VP24. Theestimated binding free energy of VP40 is −3.57 kcal/mol, the VP35 binding free energy is −7.18 kcal/mol. The VP24 binding free energy is −8.5 kcal/mol. This study showed that Andrographolide have high binding affinity and exhibit better interactions with all the Ebola Virus Protein receptors. This study will help to identify the new drug development for the EBOLA virus.

  12. Proteomics Study on Nonallergic Hypersensitivity Induced by Compound 4880 and Ovalbumin.

    Directory of Open Access Journals (Sweden)

    Yubin Xu

    Full Text Available Nonallergic hypersensitivity reaction (NHR accounts for more than 77% of all immune-mediated immediate hypersensitivity reactions and has become a serious threat to public health. Here, proteomics was used to study the NHR mechanism of two typical substances, the compound 4880 and ovalbumin. Twelve different proteins were suggested as potential biomarkers for examining the NHR mechanism, and our results revealed that the mechanism mainly encompassed 2 processes, i.e., generation and effect processes. The generation process could be classified as direct stimulation, complement (classical and alternative, coagulation, kallikrein-kinin, and integrated pathways. Thus glutathione peroxidase 1, terminal complement complex (complement factor 4d and Bb, coagulation 13, kininogen-1, and IgE could be used as candidate biomarkers for the indication of the corresponding pathways respectively, the proteins were further confirmed by ELISA. And the effect process was mainly composed of histamine as well as proteins such as DCD and MYLPF, which could be used as important indices for the symptoms of NHR. Our study differs from previous studies in that C4880 was found to not only be involved in the direct stimulation pathway, but also in the activated complement and kallikrein-kinin pathways through the coagulation pathway. We also report for the first time that ovalbumin-induced NHR could be a combination of the coagulation, classical complement, and integrated pathways.

  13. An interlaboratory study of perfluorinated alkyl compound levels in human plasma

    Science.gov (United States)

    Longnecker, Matthew P.; Smith, Cynthia S.; Kissling, Grace E.; Hoppin, Jane A.; Butenhoff, John L.; Decker, Emily; Ehresman, David J.; Ellefson, Mark E.; Flaherty, John; Gardner, Michael S.; Langlois, Eric; LeBlanc, Alain; Lindstrom, Andrew B.; Reagen, William K.; Strynar, Mark J.; Studabaker, William B.

    2010-01-01

    We conducted an interlaboratory study which differed from the typical study of this type because of its emphasis on comparing intralaboratory variability in results. We sent specimens to six laboratories experienced in the analysis of perfluorinated alkyl compounds in blood matrices and that use stringent procedures to control and assure accuracy and precision. Each received an identical set of 60 plasma specimens that were analyzed in 6 completely independent batches. Split specimens were included so that within- and between-batch coefficients of variation could be calculated. All laboratories used liquid chromatography-tandem mass spectrometry (LC-MS/MS). The concentrations of perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorohexanesulfonate (PFHxS) measured in the specimens in general showed a high level of agreement, although in some cases the agreement was only moderate. The average within- and between-batch coefficient of variation for PFOS was 9.1% and 9.3%; for PFOA was 14.5% and 14.5%; and for PFHxS was 14.5% and 17.0%. The recent availability of labeled internal standards, among other advances, has facilitated improvement in the accuracy and precision of the assays. Considering the degree of between-subject variation in levels among people in background exposed populations, the results indicate that biomarker-based epidemiologic studies of associations with health could have reasonable precision. PMID:18295197

  14. Water Soluble Organic Compounds over the Eastern Mediterranean: Study of their occurrence and sources

    Science.gov (United States)

    Tziaras, T.; Spyros, A.; Mandalakis, M.; Apostolaki, M.; Stephanou, E. G.

    2010-05-01

    Fine marine aerosols influence the climate system by acting as cloud condensation nuclei (CCN) in the atmosphere. The organic chemical composition and origin of the marine fine particulate matter are still largely unknown, because of the insufficient reports on in situ studies, the large variability in the emission from the sea, from the complex transfer of gases and particles at the air-sea interface, and the transport of aerosol particles from very distant sources. As important processes of formation of marine organic aerosol production we consider: transport of terrestrial particles, secondary organic aerosol (SOA) formation from the oxidation of biogenic dimethyl-sulfide (DMS), and biogenic particle emissions through sea spray. Specific compounds related to the above-mentioned processes have been proposed as molecular markers: e.g. n-alkanoic acids and n-alkanes (terrestrial particles), levoglucosan (biomass burning aerosol), aminoacids (biological terrestrial or marine particles), methanesulphonate (MSA) (DMS oxidation), C8 and C9 dicarboxylic acids and oxo-carboxylic acids (marine SOA) and other short-chain dicarboxylic acids (marine or terrestrial SOA), and humic-like compounds (emission of marine organic carbon). In our study, we made an effort to characterize the water-soluble organic fraction of marine aerosols collected at a background sampling site of Eastern Mediterranean (Finokalia, N35o20', E25o40', Island of Crete, Greece). The sampling period was 2007-2008. In order to identify and quantify the water-soluble organic compounds of marine aerosols determined in the present study we have used gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS) and nuclear magnetic resonance spectroscopy (NMR) and ion chromatography (IC). The origin of air masses arriving in the study area was studied by using backward trajectories calculation (NOAA HYSPLIT Model). In addition, we have used the "MODIS fire products" for fire

  15. Synthesis and Structural Studies of Calcium and Magnesium Phosphinate and Phosphonate Compounds

    Science.gov (United States)

    Bampoh, Victoria Naa Kwale

    The work presented herein describes synthetic methodologies leading to the design of a wide array of magnesium and calcium based phosphinate and phosphonates with possible applications as bone scaffolding materials or additives to bone cements. The challenge to the chemistry of the alkaline earth phosphonate target compounds includes poor solubility of compounds, and poorly understood details on the control of the metal's coordination environment. Hence, less is known on phosphonate based alkaline earth metal organic frameworks as compared to transition metal phosphonates. Factors governing the challenges in obtaining crystalline, well-defined magnesium and calcium solids lie in the large metal diameters, the absence of energetically available d-orbitals to direct metal geometry, as well as the overall weakness of the metal-ligand bonds. A significant part of this project was concerned with the development of suitable reaction conditions to obtain X-ray quality crystals of the reaction products to allow for structural elucidation of the novel compounds. Various methodologies to aid in crystal growth including hydrothermal methods and gel crystallization were employed. We have used phosphinate and phosphonate ligands with different number of phosphorus oxygen atoms as well as diphosphonates with different linker lengths to determine their effects on the overall structural features. An interesting correlation is observed between the dimensionality of products and the increasing number of donor oxygen atoms in the ligands as we progress from phosphinic acid to the phosphorous acids. As an example, monophosphinate ligand only yielded one-dimensional compounds, whereas the phosphonates crystallize as one and two-dimensional compounds, and the di- and triphosphonate based compounds display two or three-dimensional geometries. This thesis provides a selection of calcium and magnesium compounds with one-dimensional geometry, as represented in a calcium phosphinate to novel

  16. A study revealing the key aroma compounds of steamed bread made by Chinese traditional sourdough

    Institute of Scientific and Technical Information of China (English)

    Guo-hua ZHANG; Tao WU; Faizan A SADIQ; Huan-yi YANG; Tong-jie LIU; Hui RUAN; Guo-qing HE

    2016-01-01

    Aroma of Chinese steamed bread (CSB) is one of the important parameters that determines the overall quality attributes and consumer acceptance. However, the aroma profile of CSB stil remains poorly understood, mainly because of relying on only a single method for aroma extraction in previous studies. Therefore, the objective of this study was to determine the volatile aroma compounds of five different samples of CSB using three different aroma extraction methods, namely solid-phase microextraction (SPME), simultaneous distilation–extraction (SDE), and purge and trap (P&T). Al samples showed a unique aroma profile, which could be attributed to their unique microbial consortia. (E)-2-Nonenal and (E,E)-2,4-decadienal were the most prevalent aromatic compounds revealed by SDE, which have not been reported previously, while ethanol and acetic acid proved to be the most dominant compounds by both SPME and P&T. Our approach of combining three different aroma extraction methods provided better insights into the aroma profile of CSB, which had remained largely unknown in previous studies.%中文概要题目:传统酸面团制备的馒头特征风味物质的研究目的:通过同时蒸馏萃取(SDE)、顶空固相微萃取(SPME)及吹扫捕集(P&T)技术结合气相色谱-嗅闻-质谱(GC-O-MS)技术对传统酸面团制备的馒头特征风味成分进行分析,并初步探讨特征风味形成机理。创新点:首次采用不同风味物质分析技术探索传统酸面团制备的馒头关键风味成分。方法:采用同时SDE、SPME及P&T方法,对不同传统酸面团制备的馒头特征风味物质进行分析。结论:SDE结果显示,反式-2-壬烯醛和反式-2,4-癸二烯醛为传统酸面团馒头中关键风味成分。SPME和P&T 方法表明乙醇和醋酸是关键风味物质。因此,需要结合不同技术方法,全面分析传统酸面团制备的馒头中特征风味成分。

  17. In vitro study of antioxidant and scavenger properties of phenolic compounds from Lychnophora species

    Directory of Open Access Journals (Sweden)

    Cristiane F. F. Grael

    2010-01-01

    Full Text Available This paper describes the antioxidant effects of thirteen phenolic compounds isolated from plants of the genus Lychnophora. Two assays were performed to evaluate these effects: a cellular test that measured the luminol-enhanced chemiluminescence produced by neutrophils stimulated with opsonized zymosan and a cell-free test involving horseradish peroxidase-H2O2-luminol. In both assays, the antioxidant activity of the phenolic compounds was dependent on their concentration and chemical structure. Our results suggest that the ability of phenolic compounds from Lychnophora species to scavenge and inhibit the generation of ROS may be a mechanism underlying the anti-inflammatory activity of extracts from Lychnophora spp.

  18. Stability studies of antiandrogenic compounds in Curcuma aeruginosa Roxb. extract.

    Science.gov (United States)

    Suphrom, Nungruthai; Srivilai, Jukkarin; Pumthong, Ganniga; Khorana, Nantaka; Waranuch, Neti; Limpeanchob, Nanteetip; Ingkaninan, Kornkanok

    2014-09-01

    Curcuma aeruginosa Roxb. extract is a 5α-reductase antagonist that can be used to treat hair loss. We aimed to study the stability of antiandrogenic constituents, germacrone and other sesquiterpene components in the extract. Germacrone and the extract were analyzed as solid forms or solublized with polyethylene glycol-40 (PEG-40) or methanol using high-performance liquid chromatography and gas chromatography with flame ionization detector. The effects of pH, temperature and light on their stability were studied. Degradation of antiandrogenic compounds in C. aeruginosa was highly sensitive to temperature especially pure anhydrous germacrone, which was completely lost within 3 days at 45°C. Curiously, degradation was slower than as a dried extract. Paradoxically, when solubilized with PEG-40, it was largely intact even after 90 days at 45°C. The MS spectrum of a major degradation product suggested that it was elemenone probably produced by Cope rearrangement. Two other putative degradation products were germacrone-1,10-epoxide and germacrone-4,5-epoxide suggesting that oxidation of double bonds was an important mechanism. Germacrone stability was unaffected by pH (2.0-9.0) but only as dried extract it was slightly degraded by light. Antiandrogenic constituents of C. aeruginosa were instable at high temperature and in solid form. Thus, the extract would be optimately stored as a solution or otherwise as solid form at low temperature. © 2014 Royal Pharmaceutical Society.

  19. Interactions of skin thickness and physicochemical properties of test compounds in percutaneous penetration studies

    DEFF Research Database (Denmark)

    Wilkinson, Simon C.; Maas, Wilfred J. M.; Nielsen, Jesper Bo

    2006-01-01

    conditions was measured using flow through cells for 8-24 h. Saline (adjusted to pH 7.4) was used as receptor fluid, with BSA added for studies with testosterone and propoxur. Following exposure, the remaining surface dose was removed by swabbing and the skin digested prior to scintillation counting. Results......Abstract   Objectives: To determine the effect of skin thickness on the percutaneous penetration and distribution of test compounds with varying physicochemical properties using in vitro systems. Studies were carried out in accordance with OECD guidelines on skin absorption tests. Methods......: Percutaneous penetration of caffeine (log P -0.01), testosterone (log P 3.32), propoxur (log P 1.52) (finite dose in ethanol to water vehicle ratio) and butoxyethanol (log P 0.83) (undiluted finite dose or as an infinite dose 50% [v/v] aqueous solution) through skin of varying thicknesses under occluded...

  20. Interactions of skin thickness and physicochemical properties of test compounds in percutaneous penetration studies

    DEFF Research Database (Denmark)

    Wilkinson, Simon C.; Maas, Wilfred J. M.; Nielsen, Jesper Bo

    2006-01-01

    Abstract   Objectives: To determine the effect of skin thickness on the percutaneous penetration and distribution of test compounds with varying physicochemical properties using in vitro systems. Studies were carried out in accordance with OECD guidelines on skin absorption tests. Methods......: Percutaneous penetration of caffeine (log P -0.01), testosterone (log P 3.32), propoxur (log P 1.52) (finite dose in ethanol to water vehicle ratio) and butoxyethanol (log P 0.83) (undiluted finite dose or as an infinite dose 50% [v/v] aqueous solution) through skin of varying thicknesses under occluded...... conditions was measured using flow through cells for 8-24 h. Saline (adjusted to pH 7.4) was used as receptor fluid, with BSA added for studies with testosterone and propoxur. Following exposure, the remaining surface dose was removed by swabbing and the skin digested prior to scintillation counting. Results...

  1. Sensory Threshold Studies of Picrocrocin, the Major Bitter Compound of Saffron.

    Science.gov (United States)

    Chrysanthou, Andreas; Pouliou, Evangelia; Kyriakoudi, Anastasia; Tsimidou, Maria Z

    2016-01-01

    This study is part of a wider project on the bitter taste of saffron and its preparations. A deeper knowledge on the taste perception of picrocrocin is necessary in order to develop products that satisfy consumer senses and provide them with adequate amounts of saffron major constituents, also appreciated for bioactivity. A systematic approach on the bitterness of picrocrocin, the major responsible compound, was conducted. A panel was trained specifically for the determination of taste detection and recognition thresholds of picrocrocin, which were found to be 5.34 and 7.26 mg/L, respectively, using the Ascending Forced Choice of Limits methodology. The threshold values were examined in water in absence and presence of other saffron constituents and ethanol and were found to decrease when served hot (61 ± 4 °C). Bitterness was enhanced in 40% (v/v) aqueous ethanol. In both aqueous and ethanol extracts, the presence of saffron volatiles improved bitterness perception. The usefulness of the study was tested in the case of commercial saffron based infusions. © 2015 Institute of Food Technologists®

  2. Liquid chromatography tandem mass spectrometry analysis of photodegradation of a diazo compound: a mechanistic study.

    Science.gov (United States)

    Meetani, M A; Hisaindee, S M; Abdullah, F; Ashraf, S S; Rauf, M A

    2010-06-01

    The photolytic degradation of the diazo dye, Amido Black, using UV/H(2)O(2) has been carried out experimentally and parameters for most efficient dye degradation have been determined. The degradation of the dye was followed by UV-Vis spectroscopy, HPLC, and LC-MS and is proposed to be initiated by ()OH radicals formed by the photolysis of H(2)O(2). A detailed study was also carried out using LC-MS and LC-MS/MS to determine the degradation pathway of the dye as well as to identify some of the intermediate products formed. Our results suggest that Amido Black degradation occurs preferentially by ()OH radical attack at the more electron rich diazo functionality of the molecule. Furthermore, evidence is presented that subsequent steps in this diazo dye degradation pathway include radical denitration, radical desulfonation and radical diazotization. This report is one of the very few studies that have proposed possible mechanistic pathways for the degradation pathways of a diazo compound.

  3. Computational studies on DNA recognition of novel organic and copper anti-tumor compounds

    Science.gov (United States)

    Nascimento, Rafael R.; Gonçalves, Marcos B.; Petrilli, Helena M.; Ferreira, Ana M. D. C.; Ippoliti, Emiliano; Dreyer, Jens; Carloni, Paolo

    2013-03-01

    The ability of many organic and coordination compounds to bind to DNA and/or damage cellular structures has been largely exploited in anticancer research. Identifying DNA recognition mechanisms have thus important impact on the chemical biology of gene expression and the development of new drugs and therapies. Previous studies on copper(II) complexes with oxindole-Schiff base ligands have shown their potential anti-tumor activity towards different cells, inducing apoptosis through a preferential attack to DNA and/or mitochondria [SIL11]. The binding mechanism of the organic and copper(II) complexes [Cu(isaepy)2]2 + (1) and [Cu(isaenim)]2 + (2) and their modulation at DNA is investigated through theoretical studies. Here we adopted a multi-scale procedure to simulate this large system using molecular docking and classical molecular dynamics. Hybrid Car-Parrinello/Molecular Mechanics calculations were applied to parameterize the copper(II) complexes by using the force matching approach. Free energies of binding are investigated by metadynamics enhanced sampling methods[VAR08]. [SIL11] V. C. da Silveira et. al. JIB 105 (2011) 1692.[VAR08] A. V. Vargiu et. al. Nucl. Acids Res. 36 (2008) 5910.

  4. Thermodynamic and kinetic study of volatile compounds in biopolymer based dispersions.

    Science.gov (United States)

    Samavati, Vahid; Emam-Djomeh, Zahra; Mehdinia, Ali

    2014-01-01

    Partitioning and release of ethyl acetate and diacetyl from two matrices with a different composition was studied by applying static head space gas chromatography. Two matrices with a different composition have been developed: one containing carbohydrates (Tragacanth gum) and in the second one, called complex matrix, a lipid (oleic acid) was added. The roles of carbohydrate (Tragacanth gum) and lipid (oleic acid) on the retention of all the aroma compounds were pointed out. Changes in the composition of matrices exhibited a considerable effect on the thermodynamic component as expressed by the air/liquid partition coefficient (Ka/l) values at equilibrium (20 °C). The kinetic study of the release from these matrices had shown a decrease of the initial rate of release (Ri) by reference with water. The rheological properties of all matrices were investigated and the flow behaviour of all matrices was successfully modelled with power law and Ellis models and power law model was found as the better model to describe the flow behaviour of dispersions.

  5. High-resolution x-ray absorption spectroscopy studies of metal compounds in neurodegenerative brain tissue

    Science.gov (United States)

    Collingwood, J. F.; Mikhaylova, A.; Davidson, M. R.; Batich, C.; Streit, W. J.; Eskin, T.; Terry, J.; Barrea, R.; Underhill, R. S.; Dobson, J.

    2005-01-01

    Fluorescence mapping and microfocus X-ray absorption spectroscopy are used to detect, locate and identify iron biominerals and other inorganic metal accumulations in neurodegenerative brain tissue at sub-cellular resolution (reviewed. Synchrotron X-rays are used to map tissue sections for metals of interest, and XANES and XAFS are used to characterise anomalous concentrations of the metals in-situ so that they can be correlated with tissue structures and disease pathology. Iron anomalies associated with biogenic magnetite, ferritin and haemoglobin are located and identified in an avian tissue model with a pixel resolution ~5 microns. Subsequent studies include brain tissue sections from transgenic Huntington's mice, and the first high-resolution mapping and identification of iron biominerals in human Alzheimer's and control autopsy brain tissue. Technical developments include use of microfocus diffraction to obtain structural information about biominerals in-situ, and depositing sample location grids by lithography for the location of anomalies by conventional microscopy. The combined techniques provide a breakthrough in the study of both intra- and extra-cellular iron compounds and related metals in tissue. The information to be gained from this approach has implications for future diagnosis and treatment of neurodegeneration, and for our understanding of the mechanisms involved.

  6. Study of the formation mechanisms of some volatile compounds during the aging of sweet fortified wines.

    Science.gov (United States)

    Cutzach, I; Chatonnet, P; Dubourdieu, D

    1999-07-01

    Sweet fortified wines, traditionally aged under strong oxidation conditions, have a characteristic aroma. An experimental laboratory study investigated the aging of red and white sweet fortified wines under various conditions. The formation of various molecules, previously identified as characteristic of the aroma of this type of wine, was monitored by analysis. The development of these compounds during accelerated aging was affected by oxidation and the color of the wine. Among the molecules studied, sotolon [3-hydroxy-4, 5-dimethyl-2(5H)-furanone] was one of the few molecules present in concentrations above the perception threshold, in both red and white wines. Buildup was strongly affected by the presence of oxygen in white wine subjected to accelerated aging. (Ethoxymethyl)furfural, formed from 5-(hydroxymethyl)furfural, and furfural, derived from sugars, are also involved in the aroma of sweet fortified white wines aged in oxygen-free conditions. The substances most characteristic of accelerated aging of sweet fortified red wines were 5-(hydroxymethyl)furfural, acetylformoin, and hydroxymaltol, the formation of which is affected by oxidation, and dihydromaltol, formed in the absence of oxidation.

  7. Organic Compounds Detected in Deciduous Teeth: A Replication Study from Children with Autism in Two Samples

    Directory of Open Access Journals (Sweden)

    Raymond F. Palmer

    2015-01-01

    Full Text Available Biological samples are an important part of investigating toxic exposures and disease outcomes. However, blood, urine, saliva, or hair can only reflect relatively recent exposures. Alternatively, deciduous teeth have served as a biomarker of early developmental exposure to heavy metals, but little has been done to assess organic toxic exposures such as pesticides, plastics, or medications. The purpose of our study was to determine if organic chemicals previously detected in a sample of typically developing children could be detected in teeth from a sample of children with autism. Eighty-three deciduous teeth from children with autism spectrum disorders (ASD were chosen from our tooth repository. Organic compounds were assessed using liquid chromatography tandem mass spectrometry and gas chromatography methods. Consistent with a prior report from Camann et al., (2013, we have demonstrated that specific semivolatile organic chemicals relevant to autism etiology can be detected in deciduous teeth. This report provides evidence that teeth can be useful biomarkers of early life exposure for use in epidemiologic case-control studies seeking to identify differential unbiased exposures during development between those with and without specific disorders such as autism.

  8. In Situ and Laboratory Studies on the Fate of Specific Organic Compounds in an Anerobic Landfill Leachate Plume, 1. Experimental Conditions and Fate of Phenolic Compounds

    DEFF Research Database (Denmark)

    Nielsen, Per Henning; Albrechtsen, Hans-Jørgen; Heron, Gorm;

    1995-01-01

    microcosm experiments performed and the results on the fate of 7 phenolic compounds. Part 2 of this series of papers, also published in this issue, presents the results on the fate of 8 aromatic compounds and 4 chlorinated aliphatic compounds. The redox conditions in the plume were characterized...... by in situ and laboratory experiments, both concerning redox conditions and the fate of the phenolic compounds. However, for phenol and 2,4-dichlorophenol, transformation was observed in some in situ experiments but not in the corresponding laboratory experiments. In some experiments, this could be explained...

  9. Flexible metal-organic framework compounds: In situ studies for selective CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Allen, A.J., E-mail: andrew.allen@nist.gov [Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899-8520 (United States); Espinal, L.; Wong-Ng, W. [Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899-8520 (United States); Queen, W.L. [NIST Center for Neutron Research, Gaithersburg, MD 20899-6102 (United States); The Molecular Foundry, Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA 94720 (United States); Brown, C.M. [NIST Center for Neutron Research, Gaithersburg, MD 20899-6102 (United States); Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE 19716 (United States); Kline, S.R. [NIST Center for Neutron Research, Gaithersburg, MD 20899-6102 (United States); Kauffman, K.L. [National Energy Technology Laboratory (NETL), US Department of Energy, Pittsburgh, PA 15236 (United States); Culp, J.T. [National Energy Technology Laboratory (NETL), US Department of Energy, Pittsburgh, PA 15236 (United States); URS Corporation, South Park, PA 15219 (United States); Matranga, C. [National Energy Technology Laboratory (NETL), US Department of Energy, Pittsburgh, PA 15236 (United States)

    2015-10-25

    Results are presented that explore the dynamic structural changes occurring in two highly flexible nanocrystalline metal-organic framework (MOF) compounds during the adsorption and desorption of pure gases and binary mixtures. The Ni(1,2-bis(4-pyridyl)ethylene)[Ni(CN){sub 4}] and catena-bis(dibenzoylmethanato)-(4,4′-bipyridyl)nickel(II) chosen for this study are 3-D and 1-D porous coordination polymers (PCP) with a similar gate opening pressure response for CO{sub 2} isotherms at 303 K, but with differing degrees of flexibility for structural change to accommodate guest molecules. As such, they serve as a potential model system for evaluating the complex kinetics associated with dynamic structure changes occurring in response to gas adsorption in flexible MOF systems. Insights into the crystallographic changes occurring as the MOF pore structure expands and contracts in response to interactions with CO{sub 2}, N{sub 2}, and CO{sub 2}/N{sub 2} mixtures have been obtained from in situ small-angle neutron scattering and neutron diffraction, combined with ex situ X-ray diffraction structure measurements. The role of structure in carbon capture functionality is discussed with reference to the ongoing characterization challenges and a possible materials-by-design approach. - Graphical abstract: We present in situ small-angle neutron scattering results for two flexible metal-organic frameworks (MOFs). The figure shows that for one (NiBpene, high CO{sub 2} adsorption) the intensity of the Bragg peak for the expandable d-spacing most associated with CO{sub 2} adsorption varies approximately with the isotherm, while for the other (NiDBM-Bpy, high CO{sub 2} selectivity) the d-spacing, itself, varies with the isotherm. The cartoons show the proposed modes of structural change. - Highlights: • Dynamic structures of two flexible MOF CO{sub 2} sorbent compounds are compared in situ. • These porous solid sorbents serve as models for pure & dual gas adsorption. • Different

  10. Evaluation of photoionization detector performance in photocatalytic studies for removing volatile organic compounds

    Directory of Open Access Journals (Sweden)

    Masoud Rismanchian

    2012-01-01

    Full Text Available Aims: The aim of this study was to evaluate the performance of photoionization detector (PID system as a substitution for gas chromatography in the measurement of a 3 xylene isomer mixtures as a representative of the volatile organic compounds in photocatalytic studies. Materials and Methods: This study has been carried out by using test setup for generating known concentrations from equal ratio of 3 xylene isomers. The concentration values to be evaluated were classified into 4 concentration ranges from 0.1 of threshold limit values (TLV to 2 of TLV to evaluate the PID system appliance compared with that in the reference method. The test was done 4 times for each evaluation concentration in 3 relative humidity levels (0%, 20%, and 80%. Results: The correlation between the PID results and the National Institue of Occupational Safety and Health (NIOSH reference method results in an atmosphere with relative humidity of 0%, 20%, and 80% were good and, respectively, were 0.993, 0.992, and 0.991 and total correlation was 0.989. The paired t test indicates a significant difference between actual concentrations in reference method and the extracted concentration from PID. Conclusions: Although the results presented by PID in the present study are different from those extracted from the reference method (from 10 to 260 ppm, the equipment response is linear. So, the results are acceptable in photocatalytic studies in case the contaminant concentration is measured by the same equipment either before or after the reactor for calculation of the removal efficiency. PID calibration with the test material(s is recommended.

  11. Mining Molecular Pharmacological Effects from Biomedical Text: a Case Study for Eliciting Anti-Obesity/Diabetes Effects of Chemical Compounds.

    Science.gov (United States)

    Dura, Elzbieta; Muresan, Sorel; Engkvist, Ola; Blomberg, Niklas; Chen, Hongming

    2014-05-01

    In the pharmaceutical industry, efficiently mining pharmacological data from the rapidly increasing scientific literature is very crucial for many aspects of the drug discovery process such as target validation, tool compound selection etc. A quick and reliable way is needed to collect literature assertions of selected compounds' biological and pharmacological effects in order to assist the hypothesis generation and decision-making of drug developers. INFUSIS, the text mining system presented here, extracts data on chemical compounds from PubMed abstracts. It involves an extensive use of customized natural language processing besides a co-occurrence analysis. As a proof-of-concept study, INFUSIS was used to search in abstract texts for several obesity/diabetes related pharmacological effects of the compounds included in a compound dictionary. The system extracts assertions regarding the pharmacological effects of each given compound and scores them by the relevance. For each selected pharmacological effect, the highest scoring assertions in 100 abstracts were manually evaluated, i.e. 800 abstracts in total. The overall accuracy for the inferred assertions was over 90 percent.

  12. Study on the presence and influence of phenolic compounds in callogenesis and somatic embryo development of cocoa (Theobroma cacao L..

    Directory of Open Access Journals (Sweden)

    Sulistyani Pancaningtyas

    2015-04-01

    Full Text Available Cocoa (Theobroma cacao L. like most tropical trees is recalcitrant in tissue culture. Somatic embryogenesis is generally efficient micropropagation technique to multiply elite material. However, Somatic embryogenesis in cocoa is difficult and this species is considered as recalcitrant. One of the factors often considered as a component of in vitro recalsitrance is a high phenolic content and oxidation of these compounds. In cocoa tissue culture accumulate large amounts of poliphenolics compounds which probably impair further development. This study was conducted to investigate the composition of phenolic compounds in cocoa flower and leaves, and their changes troughout the somatic embryogenesis process. Calli were induced in cacao floral and leaves explants on a half-strenght Murashige and Skoog medium containing 30 g/L Glucose and combination of 2,4 dichlorophenoxyacetic acid (2,4 D with kinetin (kin. Total polyphenol content was observed on Sulawesi 1 cocoa clone. Embryogenic and non-embryogenic callus were also compared. The percentage of callus production from flower tissue is 85%, percentage of embryogenic callus 40 %, although the percentage of somatic embryo production from embryogenic callus callus is 70%. The conservation of callus into somatic embryos followed by decline in phenol content and an increase in peroxidase. The synthesis kinetics for these compounds in calli, under different somatic embryogenesis conditions, revealed a higher concentration under non-embryogenic conditions. So that, phenolic compound can influence the production of calli and an absence the phenolic compound can enhance production of somatic embryo.

  13. Atomistic studies of grain boundaries and heterophase interfaces in alloys and compounds. Final report, July 1987-August 1998

    Energy Technology Data Exchange (ETDEWEB)

    Vitek, Vaclav

    1998-08-01

    The overarching goal of the research supported by this grant was investigation of the structure and properties of interfaces in multicomponent systems by atomistic modeling. Initially, the research was devoted to studies of segregation to grain boundaries in binary disordered alloys. The next step was then studies of the structure and properties of grain boundaries in ordered compounds, specifically Ni3Al and NiAl, and grain boundary segregation in these compounds in the case of off-stoichiometry. Finally, the structure of Nb/sapphire interfaces, in particular the core configurations of the misfit dislocations, was studied.

  14. Chromatographic Study of Phenolic Compounds in Medicinal Plants Alchemilla subcrenata Buser and Veronica chamaedrys L.

    Directory of Open Access Journals (Sweden)

    Zhivetev M.A.

    2016-02-01

    Full Text Available The objects of investigation were leaves and inflorescences of Alchemilla subcrenata and Veronica chamaedry, growing on the left bank at 700 m from the edge of Lake Baikal. Some small differences in the quantity and quality of phenolic compounds in the leaves of one species even selected at one time were found. At the same time, differences in the quantity and quality of phenolic compounds in the different times of the day were even more pronounced. In the inflorescences of Alchemilla subcrenata the dynamics of flavonoids has been characterized by more stable composition than in its leaves. For Veronica's tissues and organs more variety of seasonal cocktail of phenolic compounds than in the Alchemilla subcrenata was detected. Expect a variety of phenolic compounds in inflorescences of Veronica seasonal cocktail was higher than in the leaves.

  15. Friction, wear, and thermal stability studies of some organotin and organosilicon compounds

    Science.gov (United States)

    Jones, W. R., Jr.

    1973-01-01

    Thermal decomposition temperatures were determined for a number of organotin and organosilicon compounds. A ball-on-disk sliding friction apparatus was used to determine the friction and wear characteristics of two representative compounds, (1) 3-tri-n-butylstannyl (diphenyl) and (2) 3-tri-n-butylsilyl (diphenyl). Friction and wear test conditions included a 1-kg load, 25 to 225 C disk temperatures, and a dry air atmosphere. The tin and silicon compounds yielded friction and wear results either lower than or similar to those obtained with a polyphenyl ether and a C-ether. The maximum thermal decomposition temperatures obtained in the silicon and tin series were 358 and 297 C, respectively. Increasing the steric hindrance around the silicon or tin atoms increased the thermal stability. Future work with these compounds will emphasize their use as antiwear additives rather than base fluids.

  16. Organophosphorus Compound DEPBT as a Coupling Reagent for Oligopeptides and Peptoids Synthesis: Studies on Its Mechanism

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Some oligopeptidcs and peptoids were synthesized by applying the organophosphorus compound DEPBT as a coupling rcagent. D-Biotin-OOBt was obtained unexpcctcdly. A proposed reaction mechanism for DEPBT-mediated coupling was proved.

  17. Compounds of lanthanide picrates and 2-azacyclononanone (aza): synthesis, characterization and thermal study

    Energy Technology Data Exchange (ETDEWEB)

    Marinho, E.P.; Araujo Melo, D.M.; Zinner, L.B.; Zinner, K. [UFRN, Natal (Brazil). Dept. de Quimica; Xavier de Matos, J.E. [Departamento de Quimica Organica e Inorganica, UFC, Caixa Postal 12200, CEP 60001-970 Fortaleza CE (Brazil)

    1998-07-24

    Addition compounds between lanthanide(III) picrates and azacyclononanone(aza) were characterized by spectroscopic, microanalytical and X-ray data, with special emphasis on thermogravimetric techniques. (orig.) 10 refs.

  18. Study of thermochemical sulfate reduction mechanism using compound specific sulfur isotope analysis

    Science.gov (United States)

    Meshoulam, Alexander; Ellis, Geoffrey S.; Said Ahmad, Ward; Deev, Andrei; Sessions, Alex L.; Tang, Yongchun; Adkins, Jess F.; Liu, Jinzhong; Gilhooly, William P.; Aizenshtat, Zeev; Amrani, Alon

    2016-09-01

    The sulfur isotopic fractionation associated with the formation of organic sulfur compounds (OSCs) during thermochemical sulfate reduction (TSR) was studied using gold-tube pyrolysis experiments to simulate TSR. The reactants used included n-hexadecane (n-C16) as a model organic compound with sulfate, sulfite, or elemental sulfur as the sulfur source. At the end of each experiment, the S-isotopic composition and concentration of remaining sulfate, H2S, benzothiophene, dibenzothiophene, and 2-phenylthiophene (PT) were measured. The observed S-isotopic fractionations between sulfate and BT, DBT, and H2S in experimental simulations of TSR correlate well with a multi-stage model of the overall TSR process. Large kinetic isotope fractionations occur during the first, uncatalyzed stage of TSR, 12.4‰ for H2S and as much as 22.2‰ for BT. The fractionations decrease as the H2S concentration increases and the reaction enters the second, catalyzed stage. Once all of the oxidizable hydrocarbons have been consumed, sulfate reduction ceases and equilibrium partitioning then dictates the fractionation between H2S and sulfate (∼17‰). Experiments involving sparingly soluble CaSO4 show that during the second catalytic phase of TSR the rate of sulfate reduction exceeds that of sulfate dissolution. In this case, there is no apparent isotopic fractionation between source sulfate and generated H2S, as all of the available sulfate is effectively reduced at all reaction times. When CaSO4 is replaced with fully soluble Na2SO4, sulfate dissolution is no longer rate limiting and significant S-isotopic fractionation is observed. This supports the notion that CaSO4 dissolution can lead to the apparent lack of fractionation between H2S and sulfate produced by TSR in nature. The S-isotopic composition of individual OSCs record information related to geochemical reactions that cannot be discerned from the δ34S values obtained from bulk phases such as H2S, oil, and sulfate minerals, and

  19. Design and evaluation of a field study on the contamination of selected volatile organic compounds and wastewater-indicator compounds in blanks and groundwater samples

    Science.gov (United States)

    Thiros, Susan A.; Bender, David A.; Mueller, David K.; Rose, Donna L.; Olsen, Lisa D.; Martin, Jeffrey D.; Bernard, Bruce; Zogorski, John S.

    2011-01-01

    The Field Contamination Study (FCS) was designed to determine the field processes that tend to result in clean field blanks and to identify potential sources of contamination to blanks collected in the field from selected volatile organic compounds (VOCs) and wastewater-indicator compounds (WICs). The VOCs and WICs analyzed in the FCS were detected in blanks collected by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program during 1996-2008 and 2002-08, respectively. To minimize the number of variables, the study required ordering of supplies just before sampling, storage of supplies and equipment in clean areas, and use of adequate amounts of purge-and-trap volatile-grade methanol and volatile pesticide-grade blank water (VPBW) to clean sampling equipment and to collect field blanks. Blanks and groundwater samples were collected during 2008-09 at 16 sites, which were a mix of water-supply and monitoring wells, located in 9 States. Five different sample types were collected for the FCS at each site: (1) a source-solution blank collected at the USGS National Water Quality Laboratory (NWQL) using laboratory-purged VPBW, (2) source-solution blanks collected in the field using laboratory-purged VPBW, (3) source-solution blanks collected in the field using field-purged VPBW, (4) a field blank collected using field-purged VPBW, and (5) a groundwater sample collected from a well. The source-solution blank and field-blank analyses were used to identify, quantify, and document extrinsic contamination and to help determine the sources and causes of data-quality problems that can affect groundwater samples. Concentrations of compounds detected in FCS analyses were quantified and results were stored in the USGS National Water Information System database after meeting rigorous identification and quantification criteria. The study also utilized information provided by laboratory analysts about evidence indicating the presence of selected compounds

  20. Computational Study of Bond Dissociation Enthalpies for Lignin Model Compounds. Substituent Effects in Phenethyl Phenyl Ethers

    Energy Technology Data Exchange (ETDEWEB)

    Beste, Ariana [ORNL; Buchanan III, A C [ORNL

    2009-01-01

    Lignin is an abundant natural resource that is a potential source of valuable chemicals. Improved understanding of the pyrolysis of lignin occurs through the study of model compounds for which phenethyl phenyl ether (PhCH2CH2OPh, PPE) is the simplest example representing the dominant -O-4 ether linkage. The initial step in the thermal decomposition of PPE is the homolytic cleavage of the oxygen-carbon bond. The rate of this key step will depend on the bond dissociation enthalpy, which in turn will depend on the nature and location of relevant substituents. We used modern density functional methods to calculate the oxygen-carbon bond dissociation enthalpies for PPE and several oxygen substituted derivatives. Since carbon-carbon bond cleavage in PPE could be a competitive initial reaction under high temperature pyrolysis conditions, we also calculated substituent effects on these bond dissociation enthalpies. We found that the oxygen-carbon bond dissociation enthalpy is substantially lowered by oxygen substituents situated at the phenyl ring adjacent to the ether oxygen. On the other hand, the carbon-carbon bond dissociation enthalpy shows little variation with different substitution patterns on either phenyl ring.

  1. Experimental study of the supercritical water oxidation of recalcitrant compounds under hydrothermal flames using tubular reactors.

    Science.gov (United States)

    Cabeza, Pablo; Bermejo, M Dolores; Jiménez, Cristina; Cocero, M José

    2011-04-01

    The hydrothermal flame is a new method of combustion that takes place in supercritical water oxidation reactions when the temperature is higher than the autoignition temperature. In these conditions, waste can be completely mineralized in residence times of milliseconds without the formation of by-products typical of conventional combustion. The object of this work is to study the hydrothermal flame formation in aqueous streams with high concentrations of recalcitrant compounds: an industrial waste with a high concentration of acetic acid and various concentrated solutions of ammonia. A tubular reactor with a residence time of 0.7 s was used. Oxygen was used as the oxidant and isopropyl alcohol (IPA) as co-fuel to reach the operation temperature required. The increase of IPA concentrations in the feeds resulted in a better TOC removal. For mixtures containing acetic acid, 99% elimination of TOC was achieved at temperatures higher than 750 °C. In the case of mixtures containing ammonia, TOC removals reached 99% while maximum total nitrogen removals were never higher than 94%, even for reaction temperatures higher than 710 °C. Ignition was observed at concentrations as high as 6% wt NH(3) with 2% wt IPA while at IPA concentrations below 2% wt IPA, the ammonia did not ignite.

  2. Predictive QSPR study of the dissociation constants of diverse pharmaceutical compounds.

    Science.gov (United States)

    Mercader, Andrew G; Goodarzi, Mohammad; Duchowicz, Pablo R; Fernández, Francisco M; Castro, Eduardo A

    2010-11-01

    The objective of the article was to perform a predictive analysis, based on quantitative structure-property relationships, of the dissociation constants (pK(a)) of different medicinal compounds (e.g., salicylic acid, salbutamol, lidocaine). Given the importance of this property in medicinal chemistry, it is of interest to develop theoretical methods for its prediction. The descriptors selection from a pool containing more than a thousand geometrical, topological, quantum-mechanical, and electronic types of descriptors was performed using the enhanced replacement method. Genetic algorithm and the replacement method (RM) techniques were used as reference points. A new methodology for the selection of the optimal number of descriptors to include in a model was presented and successfully used, showing that the best model should contain four descriptors. The best quantitative structure-property relationships linear model constructed using 62 molecular structures not previously used in this type of quantitative structure-property study showed good predictive attributes. The root mean squared error of the 26 molecules test set was 0.5600. The analysis of the quantitative structure-property relationships model suggests that the dissociation constants depend significantly on the number of acceptor atoms for H-bonds and on the number of carboxylic acids present in the molecules.

  3. QSAR study on estrogenic activity of structurally diverse compounds using generalized regression neural network

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Computer-based quantitative structure-activity relationship (QSAR) model has been becoming a pow- erful tool in understanding the structural requirements for chemicals to bind the estrogen receptor (ER), designing drugs for human estrogen replacement therapy, and identifying potential estrogenic endo- crine disruptors. In this study, a simple yet powerful neural network technique, generalized regression neural network (GRNN) was used to develop a QSAR model based on 131 structurally diverse estro- gens (training set). Only nine descriptors calculated solely from the molecular structures of com- pounds selected by objective and subjective feature selections were used as inputs of the GRNN model. The predictive power of the built model was found to be comparable to that of the more traditional techniques but requiring significantly easy implementation and a shorter computation-time. The ob- tained result indicates that the proposed GRNN model is robust and satisfactory, and can provide a feasible and practical tool for the rapid screening of the estrogenic activity of organic compounds.

  4. Mechanistic Studies of Anti-Hyperpigmentary Compounds: Elucidating Their Inhibitory and Regulatory Actions

    Directory of Open Access Journals (Sweden)

    Rosanna Y. Y. Lam

    2014-08-01

    Full Text Available Searching for depigmenting agents from natural sources has become a new direction in the cosmetic industry as natural products are generally perceived as relatively safer. In our previous study, selected Chinese medicines traditionally used to treat hyperpigmentation were tested for anti-hyperpigmentary effects using a melan-a cell culture model. Among the tested chemical compounds, 4-ethylresorcinol, 4-ethylphenol and 1-tetradecanol were found to possess hypopigmentary effects. Western blot analysis, reverse transcriptase polymerase chain reaction (RT-PCR, cyclic adenosine monophosphate (cAMP assay, protein kinase A (PKA activity assay, tyrosinase inhibition assay and lipid peroxidation inhibition assay were performed to reveal the underlying cellular and molecular mechanisms of the hypopigmentary effects. 4-Ethylresorcinol and 4-ethylphenol attenuated mRNA and protein expression of tyrosinase-related protein (TRP-2, and possessed antioxidative effect by inhibiting lipid peroxidation. 1-Tetradecanol was able to attenuate protein expression of tyrosinase. The hypopigmentary actions of 4-ethylresorcinol, 4-ethylphenol and 1-tetradecanol were associated with regulating downstream proteins along the PKA pathway. 4-Ethylresorcinol was more effective in inhibiting melanin synthesis when compared to 4-ethylphenol and 1-tetradecanol.

  5. Moessbauer study of the cubic Laves phase intermetallic compound TmFe/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Bleaney, B.; Bowden, G.J.; Cadogan, J.M. (New South Wales Univ., Kensington (Australia). School of Physics); Day, R.K.; Dunlop, J.B. (Commonwealth Scientific and Industrial Research Organization, Lindfield (Australia). Div. of Applied Physics)

    1982-04-01

    The results of a /sup 169/Tm and /sup 57/Fe Moessbauer study of the cubic Laves compound TmFe/sub 2/ over the temperature range 1.3-550 K are presented and discussed. The new results are used, in conjunction with existing NMR, Moessbauer and magnetic anisotropy data for TmFe/sub 2/ and Tm metal, to deduce a value of Psub(4f) 536 +- 14 MHz for the saturation value of the first excited state of the /sup 169/Tm nucleus. Estimates are also given for the exchange field ..mu..sub(B)Bsub(ex)(T = O K)/ksub(B) = 153 +- 3 K acting on the Tm/sup 3 +/ ion in TmFe/sub 2/, the quadrupole moment of the I = 3/2 state of the /sup 169/Tm nucleus. Q = -1.36 +- 0.11 b, and the lattice contribution to the nuclear quadrupole interaction in Tm metal, Psub(c) = -54.8 +- 5 MHz (for Q = -1.20 +- 0.07 b) and Psub(c) = -61 +- 8 MHz (for Q = -1.36 +- 0.11 b). In addition estimates are given for the various transferred and parent hyperfine fields in TmFe.

  6. Two-electron reduction of nitroaromatic compounds by flavin mononucleotide. DFT computational study

    Directory of Open Access Journals (Sweden)

    Liudmyla K. Sviatenko

    2016-08-01

    Full Text Available The mechanism for reduction of nitroaromatic compounds by flavin mononucleotide (FMN was examined at MPWB1K/tzvp level. The solvent effects were calculated using a PCM(Pauling and SMD(Pauling solvation models for ions and neutral molecules, respectively. Calculated thermodynamics of the reduction of nitro group to nitroso group suggests consequtive four-steps’ process (electron–proton–electron–proton transfer where the first proton comes from solution, while the second one – from FMN. Water molecule releases during fourth step of the process. Electron attachment to nitrocompound and electron lose by reduced FMN facilitate the breaking of N–O bond and proton release, respectively. Calculations show that reduction of nitro group to nitroso group in studied nitrocompounds is a thermodynamically feasible with 56–59 kcal/mol Gibbs free energy release. The most easy electron transfer proceeds for TNT (2,4,6-trinitrotoluene and NTO (5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one. While the most energy release occurs during proton transfer in case of ANTA (5-amino-3-nitro-1H-1,2,4-triazole.

  7. Compounding diagnostic delays: a qualitative study of point-of-care testing in South Africa.

    Science.gov (United States)

    Engel, Nora; Davids, Malika; Blankvoort, Nadine; Pai, Nitika Pant; Dheda, Keertan; Pai, Madhukar

    2015-04-01

    Successful point-of-care (POC) testing (completion of test-and-treat cycle in one patient encounter) has immense potential to reduce diagnostic and treatment delays, and improve patient and public health outcomes. We explored what tests are done and how in public/private, rural/urban hospitals and clinics in South Africa and whether they can ensure successful POC testing. This qualitative research study examined POC testing across major diseases in Cape Town, Durban and Eastern Cape. We conducted 101 semi-structured interviews and seven focus group discussions with doctors, nurses, community health workers, patients, laboratory technicians, policymakers, hospital managers and diagnostic manufacturers. In South Africa, diagnostics are characterised by a centralised system. Most tests conducted on the spot can be made to work successfully as POC tests. The majority of public/private clinics and smaller hospitals send samples via couriers to centralised laboratories and retrieve results the same way, via internet, fax or phone. The main challenge to POC testing lies in transporting samples and results, while delays risk patient loss from diagnostic/treatment pathways. Strategies to deal with associated delays create new problems, such as artificially prolonged turnaround times, strains on human resources and quality of testing, compounding additional diagnostic and treatment delays. For POC testing to succeed, particular characteristics of diagnostic ecosystems and adaptations of professional practices to overcome associated challenges must be taken into account. © 2014 John Wiley & Sons Ltd.

  8. Correlation between the structure and biological activity studies of supramolecular coordination azodye compounds

    Directory of Open Access Journals (Sweden)

    M.I. Abou-Dobara

    2017-02-01

    Full Text Available A series of novel bidentate azodye quinoline ligands were synthesized with various p-aromatic amines like p-(OCH3, CH3, H, Cl and NO2. Novel azodye (HLn and complexes [Cu(II/Ni(II] of these ligands have been characterized on the basis of elemental analysis, molar conductance and magnetic measurements, infrared and electronic spectral studies. Suitable structures have been proposed for these complexes. The synthesized ligands and their metal complexes were screened for their antimicrobial activity against four local bacterial species, two Gram positive bacteria (Bacillus cereus and Staphylococcus aureus and two Gram negative bacteria (Escherichia coli and Klebsiella pneumoniae as well as against four local fungal species; namely Aspergillus niger, Alternaria alternata, Penicillium italicum and Fusarium oxysporium. The tested compounds have good antibacterial activity against B. cereus, E. coli and K. pneumoniae. Very low effect was detected against S. aureus and F. oxysporium. We found that the results of antifungal activity of HLn revealed that the complexes are more toxic than ligands against fungi due to the transition metal involved in the coordination. Also Cu2+ complexes are more active than Ni2+ complexes against B. cereus, E. coli and K. pneumoniae. The size of the clear zone was in the following order p-(OCH3 < CH3 < H < Cl < NO2 as expected from Hammett’s constants σR.

  9. A Study on Magnetic Decoupling of Compound-Structure Permanent-Magnet Motor for HEVs Application

    Directory of Open Access Journals (Sweden)

    Qiwei Xu

    2016-10-01

    Full Text Available The compound-structure permanent-magnet (CSPM motor is used for an electrical continuously-variable transmission (E-CVT in a hybrid electric vehicle (HEV. It can make the internal combustion engine (ICE independent of the road loads and run in the high efficiency area to improve the fuel economy and reduce the emissions. This paper studies the magnetic coupling of a new type of CSPM motor used in HEVs. Firstly, through the analysis of the parameter matching with CSPM in the HEV, we receive the same dynamic properties’ design parameters between the CSPM motor and the THS (Toyota Hybrid System of the Toyota Prius. Next, we establish the equivalent magnetic circuit model of the overall and the secondary model considering the tangential and radial flux distribution in the outer rotor of the CSPM motor. Based on these two models, we explore the internal magnetic coupling rule of the CSPM motor. Finally, finite element method analysis in 2D-ansoft is used to analyze the magnetic field distribution of the CSPM motor in different operation modes. By the result of the finite element method analysis, the internal magnetic decoupling scheme is put forward, laying the theoretical foundation for the further application of the CSPM motor in HEVs.

  10. Analysis of flow around impermeable groynes on one side of symmetrical compound channel: An experimental study

    Directory of Open Access Journals (Sweden)

    Hassan SafiAHMED

    2010-03-01

    Full Text Available This paper presents the results of an experimental study on the influences of floodplain impermeable groynes on flow structure, velocity, and water depth around the groyne(s. A wooden symmetrical compound channel was used. Groyne models with three different groyne relative lengths, 0.5, 0.75, and 1.0, were used on one floodplain with single and series arrangements. Analysis of the experimental results using the measured flow velocity and water depth values showed that flow structure, velocity, and water depth mainly depend on groyne relative length and the relative distance between series groynes. The flow velocity at the main channel centerline increased by about 40%, 60%, and 85%, and in other parts on the horizontal plane at the floodplain mid-water depth by about 75%, 125%, and 175% of its original value in cases of one-side floodplain groyne(s with relative lengths of 0.5, 0.75, and 1.0, respectively. The effective distance between two groynes in series arrangement ranges from 3 to 4 times the groyne length. Using an impermeable groyne with a large relative length in river floodplains increases the generation of eddy and roller zones downstream of the groyne, leading to more scouring and deposition. To avoid that, the groyne relative length must be kept below half the floodplain width.

  11. Use of computational modeling approaches in studying the binding interactions of compounds with human estrogen receptors.

    Science.gov (United States)

    Wang, Pan; Dang, Li; Zhu, Bao-Ting

    2016-01-01

    Estrogens have a whole host of physiological functions in many human organs and systems, including the reproductive, cardiovascular, and central nervous systems. Many naturally-occurring compounds with estrogenic or antiestrogenic activity are present in our environment and food sources. Synthetic estrogens and antiestrogens are also important therapeutic agents. At the molecular level, estrogen receptors (ERs) mediate most of the well-known actions of estrogens. Given recent advances in computational modeling tools, it is now highly practical to use these tools to study the interaction of human ERs with various types of ligands. There are two common categories of modeling techniques: one is the quantitative structure activity relationship (QSAR) analysis, which uses the structural information of the interacting ligands to predict the binding site properties of a macromolecule, and the other one is molecular docking-based computational analysis, which uses the 3-dimensional structural information of both the ligands and the receptor to predict the binding interaction. In this review, we discuss recent results that employed these and other related computational modeling approaches to characterize the binding interaction of various estrogens and antiestrogens with the human ERs. These examples clearly demonstrate that the computational modeling approaches, when used in combination with other experimental methods, are powerful tools that can precisely predict the binding interaction of various estrogenic ligands and their derivatives with the human ERs.

  12. Antibacterial activity of fluoride compounds and herbal toothpastes on Streptococcus mutans: an in vitro study.

    Science.gov (United States)

    Randall, J P; Seow, W K; Walsh, L J

    2015-09-01

    Streptococcus mutans is an important bacterial species implicated in dental caries. This laboratory study compared the antimicrobial activity of a number of fluoride containing and herbal dentifrices and their components against S. mutans. An agar diffusion method was used with Mueller-Hinton agar. Wells were filled with either 10 commercial fluoride or 6 herbal dentifrices, or with solutions of various fluoride compounds, sodium lauryl sulphate, sodium benzoate, chlorhexidine digluconate or triclosan. Diameters of zones of bacterial growth inhibition surrounding the wells were measured using a micrometer. Significant differences were found for growth inhibition between the 10 fluoridated dentifrices (p fluoride type or fluoride concentration. The antibacterial activities of the 6 herbal toothpastes varied, with Herbal Fresh being the strongest. Sodium lauryl sulphate showed strong antimicrobial activity against S. mutans at the levels used in dentifrices. Antimicrobial activity of commercial dentifrices against S. mutans may be exerted by components other than fluoride. Ingredients such as triclosan and sodium lauryl sulphate have larger antimicrobial effects than fluorides in this model. © 2015 Australian Dental Association.

  13. Study on the prediction of visible absorption maxima of azobenzene compounds

    Institute of Scientific and Technical Information of China (English)

    LIU Jun-na; CHEN Zhi-rong; YUAN Shen-feng

    2005-01-01

    The geometries of azobenzene compounds are optimized with B3LYP/6-311 G* method, and analyzed with nature bond orbital, then their visible absorption maxima are calculated with TD-DFT method and ZINDO/S method respectively. The results agree well with the observed values. It was found that for the calculation of visible absorption using ZINDO/S method could rapidly yield better results by adjusting OWFπ-π (the relationship between π-π overlap weighting factor) value than by the TD-DFT method. The method of regression showing the linear relationship between OWFπ-π and BLN-N (nitrogen-nitrogen bond lengths) as OWFπ-π=-8.1537+6.5638BLN-N, can be explained in terms of quantum theory, and also be used for prediction of visible absorption maxima of other azobenzne dyes in the same series. This study on molecules' orbital geometry indicates that their visible absorption maxima correspond to the electron transition from HOMO (the highest occupied molecular orbital) to LUMO (the lowest unoccupied molecular orbital).

  14. Multigram Synthesis and in Vivo Efficacy Studies of a Novel Multitarget Anti-Alzheimer’s Compound

    Directory of Open Access Journals (Sweden)

    Irene Sola

    2015-03-01

    Full Text Available We describe the multigram synthesis and in vivo efficacy studies of a donepezil‒huprine hybrid that has been found to display a promising in vitro multitarget profile of interest for the treatment of Alzheimer’s disease (AD. Its synthesis features as the key step a novel multigram preparative chromatographic resolution of intermediate racemic huprine Y by chiral HPLC. Administration of this compound to transgenic CL4176 and CL2006 Caenorhabditis elegans strains expressing human Aβ42, here used as simplified animal models of AD, led to a significant protection from the toxicity induced by Aβ42. However, this protective effect was not accompanied, in CL2006 worms, by a reduction of amyloid deposits. Oral administration for 3 months to transgenic APPSL mice, a well-established animal model of AD, improved short-term memory, but did not alter brain levels of Aβ peptides nor cortical and hippocampal amyloid plaque load. Despite the clear protective and cognitive effects of AVCRI104P4, the lack of Aβ lowering effect in vivo might be related to its lower in vitro potency toward Aβ aggregation and formation as compared with its higher anticholinesterase activities. Further lead optimization in this series should thus focus on improving the anti-amyloid/anticholinesterase activity ratio.

  15. Kinetic Study of the Acid Degradation of Lignin Model Compound Intermediates

    Energy Technology Data Exchange (ETDEWEB)

    Sturgeon, M.; Kim, S.; Chmely, S. C.; Foust, T. D.; Beckham, G. T.

    2012-01-01

    Lignin is a major constituent of biomass, which remains underutilized in selective biomass conversion strategies to renewable fuels and chemicals. Here we are interested in understanding the mechanisms related to the acid deconstruction of lignin with a combined theoretical and experimental approach. Two model dimers with a b-O-4 aryl ether linkage (2-phenoxy-1-phenethanol and 2-phenoxy-1-phenyl-1,3 propanediol) were synthesized and deconstructed in H2SO4. The major products of the acidolysis of the b-O-4 compounds consisted of phenol and two aldehydes, phenylacetaldehyde and benzaldehyde. Quantum mechanical calculations were employed to elucidate possible deconstruction mechanisms with transition state theory. To confirm the proposed mechanisms a kentic study of several possible intermediates was done under similar acidolysis conditions. Epoxystyrene and 1-phenyl-1,2-ethandiol were used as intermediates. 2-phenoxyvinylbenzene was synthesized and subsequently deconstructed in H2SO4. The kinetics and product distribution of these intermediates were then used in confirming our proposed mechanisms.

  16. Yeast as a model system to study metabolic impact of selenium compounds

    Directory of Open Access Journals (Sweden)

    Enrique Herrero

    2015-04-01

    Full Text Available Inorganic Se forms such as selenate or selenite (the two more abundant forms in nature can be toxic in Saccharomyces cerevisiae cells, which constitute an adequate model to study such toxicity at the molecular level and the functions participating in protection against Se compounds. Those Se forms enter the yeast cell through other oxyanion transporters. Once inside the cell, inorganic Se forms may be converted into selenide through a reductive pathway that in physiological conditions involves reduced glutathione with its consequent oxidation into diglutathione and alteration of the cellular redox buffering capacity. Selenide can subsequently be converted by molecular oxygen into elemental Se, with production of superoxide anions and other reactive oxygen species. Overall, these events result in DNA damage and dose-dependent reversible or irreversible protein oxidation, although additional oxidation of other cellular macromolecules cannot be discarded. Stress-adaptation pathways are essential for efficient Se detoxification, while activation of DNA damage checkpoint and repair pathways protects against Se-mediated genotoxicity. We propose that yeast may be used to improve our knowledge on the impact of Se on metal homeostasis, the identification of Se-targets at the DNA and protein levels, and to gain more insights into the mechanism of Se-mediated apoptosis.

  17. Bach Adsorption Study for the Extraction of Silver Ions by Hydrazone Compounds from Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Abdussalam Salhin Mohamad Ali

    2012-01-01

    Full Text Available Sorbent materials based on a hydrazone Schiff base compound, C14H11BrN4O4, were prepared either by immobilizing the ligand into sol-gel (SG1 or bonding to silica (SG2. The sorbent materials were characterized by FT-IR, EDX, SEM, TEM, and TGA. The sorption characteristics of a matrix of eight transition metal ions (Ag+, Cu2+, Co2+, Ni2+, Fe3+, Pb2+, Zn2+, and Mn2+ using batch method were studied. Several key parameters that affected the extraction efficiency such as pH, contact time, metal ions concentration, and gel size (for SGl were investigated and optimized. Under the optimized conditions, the physically immobilized hydrazone sorbent (SG1 exhibits highest selectivity towards Ag+ ions, while the chemically bonded hydrazone sorbent (SG2 exhibits high extraction for all metal ions tested. However, for practical applications such as the removal and preconcentration of Ag+, the physically immobilized sorbent (SG1 is preferred.

  18. STUDY ON POLYMERIC CATALYST—PALLADIUM COMPLEX WITH RADIATION GRAFTING ACRYLONITRILE ON INORGANIC COMPOUND

    Institute of Scientific and Technical Information of China (English)

    ZHANGWanxi; CHEJitai

    1993-01-01

    Polymer bound palladium (Pd) complex catalysts with grafting acrylonitrile on inorganic compound(MgO,Y-molecular sieve and SiO2) by pre-radiation method were studies.The palladium-grafting polymers have been investigated by X-ray photoelectron spectrscopy(XPS).It is indicated that peak width of C1s and O1s spectra of MgO-g-PAN-Pd(radiation-induced graft) is wider than that of MgO-PAN-Pd(chemical method) and Peak numbers of former are one more than later.According to the report in reference,this peak is attributed to -O-C group.Thus,the graft acrylonitrile on MgO may complete through oxygen atoms im MgO and β-carbon atoms in acrylonitrile.The polymer catalyst obtained by radiation grafting is a higher active hydrogenation catalyst for olefines and better antioxic than that of one obtained by chemical method,and it has selectivity for hydrogenation catalyst.

  19. ESR studies on Er sup 3 sup + -doped YBiPt compound

    CERN Document Server

    Guener, S; Aktas, B

    2003-01-01

    The semi-metallic cubic compound YBiPt doped by Er sup 3 sup + (4f sup 1 sup 1) has been studied by ESR technique between 4 and 300 K. X-band and Q-band measurements have been performed. The angular dependence of the ESR spectra on the crystal orientation with respect to the static magnetic field has been measured. Two anisotropic lines with hyperfine peaks coming from the interaction between electronic and nuclear spins of sup 1 sup 6 sup 7 Er sup 3 sup + (I=7/2) isotopes have been observed below 30 K in the spectra. Computer modeling showed that these lines are the ESR signals from the quadruplet ground state of Er sup 3 sup + ions in the cubic crystal field. The values of crystal field parameters B sub 4 =-5.68 x 10 sup - sup 4 cm sup - sup 1 and B sub 6 =-6.64 x 10 sup - sup 6 cm sup - sup 1 have been extracted. Also an isotropic line near g=2 have been observed in both frequency bands. Dysonian lineshape of the spectra components due to the skin-depth effect shows the conducting property of the sample un...

  20. Spectroelectrochemical studies of nuclease-active zinc(II) coordination compounds from the ligands Hpyramol and Hpyrimol

    Energy Technology Data Exchange (ETDEWEB)

    Ozalp-Yaman, Seniz, E-mail: seniz@atilim.edu.t [Atilim University, Engineering Faculty, Chemistry Group, 06836 Ankara (Turkey); Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, 2300 RA Leiden (Netherlands); Hoog, Paul de; Maheswari, Palanisamy Uma; Casellas, Helene [Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, 2300 RA Leiden (Netherlands); Golobic, Amalija; Kozlevcar, Bojan [University of Ljubljana, Faculty of Chemistry and Chemical Technology, Askerceva 5, P.O. Box 537, 1001 Ljubljana (Slovenia); Gamez, Patrick; Reedijk, Jan [Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, 2300 RA Leiden (Netherlands)

    2010-12-01

    The electrochemical oxidation of four zinc(II) coordination compounds from the ligands 4-methyl-2-(2-pyridylmethyl)aminophenol (Hpyramol) and 4-methyl-2-(2-pyridylmethylene)aminophenol (Hpyrimol) with chloride or acetate as counter-ions has been studied by in situ spectroelectrochemistry in dimethylformamide (DMF). Low-temperature EPR studies of electrolyte solutions of all zinc compounds indicate the presence of a phenoxyl radical with a g-value in the range 2.070-2.099, which is illustrative for an electron delocalization over the metal centre. The final product of this oxidative process is shown to be a benzoquinone methide derivative.

  1. Magnetism and magnetocaloric effect in multicomponent Laves-phase compounds: Study and comparative analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ćwik, J., E-mail: cwikjac@ml.pan.wroc.pl

    2014-01-15

    This paper presents a review and results of comparative study of the influence of Gd on some physical properties of (R{sub 0.9}R′{sub 0.1}){sub 1−x}Gd{sub x}Co{sub 2} solid solutions with R=Dy, Ho and R′=Er, Ho and x varied from 0.05 to 0.15. Powder X-ray diffraction analysis performed at room temperature revealed that all studied solid solutions solidify with the formation of a Laves-phase MgCu{sub 2}-type structure (space group Fd−3m). The magnetization behavior and the magnetic transition are analyzed in terms of the Landau theory. The studies of magnetic properties and heat capacity showed that a relatively small Gd addition significantly increases T{sub C} of the compounds. The maximum percentage increase in T{sub C}, namely, ∼43% was observed for (Ho{sub 0.9}Er{sub 0.1}){sub 1−x}Gd{sub x}Co{sub 2}. However, the highest temperature was noted for the (Dy{sub 0.9}Ho{sub 0.1}){sub 0.85}Gd{sub 0.15}Co{sub 2} solid solution; it is T{sub C}=183.4 K. Below the ordering temperature, all samples are ferrimagnetically ordered; at high temperatures, they are Curie–Weiss paramagnets. Moreover, a small Gd addition eliminates the field-induced magnetic transition near T{sub C} and, as consequence, transforms the nature of magnetic transition from the first- to second-order. The magnetocaloric effect has been estimated in terms of both isothermal magnetic entropy and adiabatic temperature changes. The highest adiabatic temperature change ΔT{sub ad}=3 K and highest isothermal entropy change ΔS{sub mag}=12.1 J/kg K were observed for (Ho{sub 0.9}Er{sub 0.1}){sub 0.95}Gd{sub 0.05}Co{sub 2} at ∼90 K in magnetic fields of 2 T and 3 T, respectively. A decrease in the entropy change has been observed with increasing Gd content in all studied samples. The smallest values of ΔS{sub mag} were observed for the (Dy{sub 0.9}Ho{sub 0.1}){sub 1−x}Gd{sub x}Co{sub 2} solid solutions. Under an external field change of from 0 to 3 T, the maximum entropy change for (Dy{sub 0

  2. [A prospective multicenter randomized controlled clinical study on the efficacy and safety of Guaifenesin compound pseudoephedrine hydrochloride oral solution].

    Science.gov (United States)

    Lu, Quan

    2010-03-01

    To evaluate efficacy and safety of Guaifenesin compound pseudoephedrine hydrochloride oral solution for the treatment of cough, expectoration, nasal congestion and runny nose in children. This was a prospective multicenter randomized single-blind, parallel-controlled clinical study. A total of 10 centers participated in this study, the actual number of cases in line with the program was 412, of whom 205 cases in trial group were treated with Guaifenesin compound pseudoephedrine hydrochloride oral solution, and 207 cases in control group with ambroxol hydrochloride oral solution, treatment of both groups persisted for 7 days. The improvement rate of each single symptom and the combined symptoms and the overall effective rate were compared between the two groups. The adverse drug reactions and compliance were assessed as well. The treatment of both groups showed efficacy. Except sputum stickiness, the improvement of all symptoms in trial group was superior to that in the control group on the 3rd day after treatment (P Guaifenesin compound pseudoephedrine hydrochloride oral solution was 82.9% and the overall efficacy rate was 89.3%. Guaifenesin compound Pseudoephedrine hydrochloride oral solution had higher compliance and its adverse event rate was merely 0.92%. Guaifenesin compound pseudoephedrine hydrochloride oral solution showed significant efficacy and safety in children for treatment of cough, expectoration, nasal congestion and runny nose caused by common cold or acute tracheobronchitis.

  3. A STUDY ON INTERNAL FIXATION OF COMPOUND FRACTURES OF TIBIA USING INTERLOCKING NAIL WITHOUT REAMING

    Directory of Open Access Journals (Sweden)

    Pradeep Chandra

    2016-06-01

    Full Text Available As one-third of the tibial surface is subcutaneous throughout its length, open fractures are commonly encountered in this bone. The factors which determine the outcome of these fractures are severity of the injury, indicated by the degree of initial displacement, comminution and soft tissue injury and the damage to the tibial blood supply. In open fractures not only is the endosteal circulation disrupted but also the periosteal circulation, because of periosteal stripping. The various available options of treatment such as conservative short leg or long leg casting, open reduction and internal fixation with plates and screws, intramedullary fixation (Including Ender pins, Intramedullary nails and Interlocking Intramedullary nails with reaming or without reaming and external fixation techniques have their own advantages and disadvantages. The present study was conducted in the Department of Orthopaedics, Gandhi Hospital, during the period from October 2013 to November 2015, to evaluate the results of internal fixation with interlocking intramedullary nailing without reaming in the treatment of the open fractures of tibia. In our study, we got 91% good-to-excellent results evaluated by Johner and Wruh criteria. We opine that closed unreamed interlocking intramedullary nailing yields good-to-excellent results in compound diaphyseal fractures of the tibia, as this technique allows a good control over the rotations with axial stability of the fracture, thus maintaining the length of the limb and enabling early joint motion. The endosteal blood supply is also well preserved. These factors help in lowering the rates of infection, malunions and non-unions.

  4. A DFT study of volatile organic compounds adsorption on transition metal deposited graphene

    Science.gov (United States)

    Kunaseth, Manaschai; Poldorn, Preeyaporn; Junkeaw, Anchalee; Meeprasert, Jittima; Rungnim, Chompoonut; Namuangruk, Supawadee; Kungwan, Nawee; Inntam, Chan; Jungsuttiwong, Siriporn

    2017-02-01

    Recently, elevated global emission of volatile organic compounds (VOCs) was associated to the acceleration and increasing severity of climate change worldwide. In this work, we investigated the performance of VOCs removal via modified carbon-based adsorbent using density functional theory. Here, four transition metals (TMs) including Pd, Pt, Ag, and Au were deposited onto single-vacancy defective graphene (SDG) surface to increase the adsorption efficiency. Five prototypical VOCs including benzene, furan, pyrrole, pyridine, and thiophene were used to study the adsorption capability of metal-deposited graphene adsorbent. Calculation results revealed that Pd, Pt, Au, and Ag atoms and nanoclusters bind strongly onto the SDG surface. In this study, benzene, furan and pyrrole bind in the π-interaction mode using delocalized π-electron in aromatic ring, while pyridine and thiophene favor X- interaction mode, donating lone pair electron from heteroatom. In terms of adsorption, pyridine VOC adsorption strengths to the TM-cluster doped SDG surfaces are Pt4 (-2.11 eV) > Pd4 (-2.05 eV) > Ag4 (-1.53 eV) > Au4 (-1.87 eV). Our findings indicate that TM-doped SDG is a suitable adsorbent material for VOC removal. In addition, partial density of states analysis suggests that benzene, furan, and pyrrole interactions with TM cluster are based on p-orbitals of carbon atoms, while pyridine and thiophene interactions are facilitated by hybridized sp2-orbitals of heteroatoms. This work provides a key insight into the fundamentals of VOCs adsorption on carbon-based adsorbent.

  5. Performance study of compounded biocover material for methane removal based on cattle manure compost.

    Science.gov (United States)

    Wei, Wenping; Deng, Hui; Li, Guoxue; Wang, Xue; Lu, Jianjiang

    2016-01-01

    Methane is the second most significant greenhouse gas. Landfill cover soils play an important role in mitigation of methane emission from critical sources - Landfills. In this study, methane removal biocover materials based on cattle manure compost (CMC) were constructed and its performance was investigated. When comparing CH4 removal abilities of sand (S), clay soil (CS), paddy soil (PS) and CMC, CMC was the most effective biocover material for the reduction of methane emission. The maximum removal rate (Vmax) and half saturation constant (Km) of CMC peaked at 3451.25 ± 18.57 μg g(-1) h(-1) and 3.67 ± 0.02 × 10(5) ppm, respectively, which are higher than those in previous studies. Thereafter, three compounded biocover materials (CBMs) were established based on the mixture of CMC and other three materials (ratio of 2:8). The rate of the three CBMs was enhanced by 13.56, 13.27 and 16.42 times, respectively, more than the S, CS and PS by adding CMC. Saturated water content of 80% and 35 °C were found to be the optimum moisture and temperature, respectively, for CBMs. Analysis of community diversity using terminal restriction fragment length polymorphism (T-RFLP) showed that the diversity and evenness indexes of the CBMs decreased after adding CMC; Type I methanotroph was the most dominated methanotroph in the CBMs. CMC not only influenced bacterial community but also improved nutrient and CH4 removal capacity of CBMs. All results showed that CMC and CBMs could effectively remove CH4, and the screening and construction of CBMs are important for decreasing CH4 emission.

  6. Kinetic study of crystallisation of sol–gel derived calcia–alumina binary compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zahedi, Marjan; Roohpour, Nima; Ray, Asim K., E-mail: asim.ray@brunel.ac.uk

    2014-01-05

    Graphical abstract: A novel sol–gel synthesis technique is employed for the fabrication of amorphous and crystalline nanoporous C12A7. Crystalline C12A7 consists of nano-sized cages which can accommodate H{sup −}, O{sup 2−}, e{sup −} introducing remarkable characteristics. -- Highlights: • Highest levels of homogeneity and clarity in the synthesized C12A7 solution. • Sol–gel formulation of binary C12A7 in stoichiometrical ratio of 12:7. • High temperature XRD to study effect of the heating rate on crystallization. • In situ investigation in to crystallisation of C12A7 with temperature rise. • Raman and FTIR spectra for crystal structure of annealed C12A7. -- Abstract: In-situ High Temperature X-ray Diffraction (HTXRD) and Differential Scanning Calorimetric (DSC) studies were performed on a sol–gel derived binary compound of a calcia–alumina (C12A7) system consisting of calcium oxide (CaO) and aluminium oxide (Al{sub 2}O{sub 3}) in a ratio of 12:7 for in situ investigation into the phase transformations under progressively increasing thermal activation from room-temperature to 1200 °C. The crystallisation of amorphous samples formulated at room-temperature on magnesium oxide (MgO) single crystal (1 0 0) substrates was found to be complete on heat treatment at 1100 °C for 3 h. This observation was further supported by independent Fourier Transform Infrared (FTIR) and Raman Spectroscopies. Values of 348 kJ/mol and 375 kJ/mol were estimated from Kissinger plots for activation energies of crystallisation of CaO and Al{sub 2}O{sub 3} constituents, respectively.

  7. Study of LiBOB compound synthesis by vacuum process as lithium ion battery electrolytes

    Science.gov (United States)

    Lestariningsih, T.; Wigayati, E.; Ratri, C.; Sabrina, Q.

    2017-04-01

    Lithium bis (oxalato) borate or LiBOB is potential candidate to substitute LiPF6 which has many problems in lithium ion batteries. Many studies have been synthesized of electrolyte salt LiBOB to improve performance as electrolyte lithium ion batteries. In this paper we have studied the synthesis of compounds LiBOB undergoing pre-heat treatment in a vacuum. LiBOB was synthesized by mixing technical grade raw materials H2C2O4.2H2O, LiOH and H3BO3. The mixture H2C2O4.2H2O and LiOH was preheated at 60 °C for 2 h before adding H3BO3 in several time to be mortared in vacuum dryer, the mixture of the three starting materials was preheated in two steps at 70 °C for 6 h and the third step of preheating at a temperature of 100 °C. This powder was then characterized using XRD, FTIR and BET. The characterization results of LiBOB compared to commercial LiBOB powder. The XRD analysis results showed that the sample have formed LiBOB and LiBOB hydrate phase, while FTIR analysis results show the formation of functional groups of LiBOB. In addition, the BET results shows the surface area of synthesized LiBOB is 75.994 m2/g, close the surface area of commercial LiBOB, i.e 108.776 m2/g.

  8. Study of organic compounds-water interactions by partition in aqueous two-phase systems.

    Science.gov (United States)

    Madeira, Pedro P; Bessa, Ana; Teixeira, Miguel A; Álvares-Ribeiro, Luís; Aires-Barros, M Raquel; Rodrigues, Alírio E; Zaslavsky, Boris Y

    2013-12-27

    Partition coefficients of fourteen organic compounds were determined in 10 or 20 different polymer/polymer aqueous two-phase systems (ATPS) all at physiological pH (0.15M NaCl in 0.01M phosphate buffer, pH 7.4). Solute-specific coefficients characterizing different types of solute-water interactions for the compounds examined were determined by the multiple linear regression analysis. It is shown that (i) the partition behavior for the polar organic compounds is affected not only by dipole-dipole and hydrogen-bond interactions with aqueous environment but, notably, in most cases also by dipole-ion interactions; (ii) it is possible to predict partition behavior for compounds with pre-determined solute-specific coefficients in ATPS with characterized solvent features; and (iii) linear combinations of the solute-specific coefficients for the organic compounds might be useful in the development of quantitative structure-activity relationship (QSAR) analysis to describe their odor detection threshold.

  9. Computational study on fused five membered heterocyclic compounds containing tertiary oxygen

    Science.gov (United States)

    Dai, Yujie; Zhang, Tongcun; Piao, Ying'ai; Zhang, Xiuli; Hu, Yanying; Zhang, Liming; Jia, Shiru; He, Huixin

    2017-02-01

    The structure, stability and electronic properties of two fused five membered heterocyclic compounds containing tertiary oxygen have been investigated with quantum chemistry computation. The results show that 3H-4λ3-furo[1,2-a]furan (M1) and 2a1λ4-oxacyclopenta[cd]pentalene (M2) both own three Csbnd O bonds and especially in M2 the three Csbnd O bonds and angles are approximately identical. The two compounds are comparatively stable and M2 with three pentacycles is more stable than compound M1 according to the Csbnd O bond lengths, bond orders, Egap, electronegativity (χ), hardness (η), electrophilicity (ω), and aromaticity indexes. The aromaticity indexes such as NICS(0), NICS(1) and NICS(1)zz show that they both have strong aromaticity. The natural bonding orbital (NBO) analysis shows that oxygen atom takes hybrid orbitals composed of s and p orbital components to form σ(Csbnd O) bonds in compounds M1 and M2. The second order perturbation analysis shows that the occurrence of intramolecular charge transfer within the molecule exists in compound M1.

  10. Study of the Biological Activity of Novel Synthetic Compounds with Antiviral Properties against Human Rhinoviruses

    Directory of Open Access Journals (Sweden)

    Raffaello Pompei

    2011-04-01

    Full Text Available Picornaviridae represent a very large family of small RNA viruses, some of which are the cause of important human and animal diseases. Since no specific therapy against any of these viruses currently exists, palliative symptomatic treatments are employed. The early steps of the picornavirus replicative cycle seem to be privileged targets for some antiviral compounds like disoxaril and pirodavir. Pirodavir’s main weakness is its cytotoxicity on cell cultures at relatively low doses. In this work some original synthetic compounds were tested, in order to find less toxic compounds with an improved protection index (PI on infected cells. Using an amino group to substitute the oxygen atom in the central chain, such as that in the control molecule pirodavir, resulted in decreased activity against Rhinoviruses and Polioviruses. The presence of an -ethoxy-propoxy- group in the central chain (as in compound I-6602 resulted in decreased cell toxicity and in improved anti-Rhinovirus activity. This compound actually showed a PI >700 on HRV14, while pirodavir had a PI of 250. These results demonstrate that modification of pirodavir’s central hydrocarbon chain can lead to the production of novel derivatives with low cytotoxicity and improved PI against some strains of Rhinoviruses.

  11. First principles study on half-metallic properties of Heusler compounds Ti2VZ (Z=Al, Ga, and In)

    Science.gov (United States)

    Galehgirian, S.; Ahmadian, F.

    2015-01-01

    First principles calculations using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method in the framework of density functional theory (DFT) were performed to study the electronic structures and magnetic properties of new full-Heusler compounds Ti2VZ (Z=Al, Ga, and In). Electronic structure calculations showed that Ti2VZ (Z=Al, Ga, and In) compounds in AlCu2Mn-type are conventional ferrimagnets. The Ti2VAl, Ti2VGa, and Ti2VIn compounds in the CuHg2Ti-type structure have half-metallic characteristics with a respective majority band gap of 0.52, 0.51, and 0.59 eV at the equilibrium lattice parameter. The origin of half-metallicity in these compounds was also discussed. The total magnetic moments of Ti2VZ (Z=Al, Ga, and In) compounds in the CuHg2Ti-type structures were 2 μB per formula unit which were in agreement with Slater-Pauling rule (Mtot=18-Ztot). The Ti2VAl, Ti2VGa, and Ti2VIn compounds in the CuHg2Ti-type structure respectively showed half-metallic characteristics at lattice constants ranges of 6.12-7.17 Å, 5.99-7.12 Å, and 6.31-7.06 Å, indicating the lattice distortion did not affect the half-metallic properties of these compounds which makes them interesting materials in the spintronics field.

  12. Study on F-F Transitions of Powdered Neodymium Compounds by Photoacoustic Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    杨跃涛; 苏庆德; 赵贵文; 张淑仪

    2002-01-01

    Photoacoustic (PA) spectra of powdered neodymium oxide (Nd2O3 (A type)), neodymium hydrated chloride (NdCl3*6H2O) and neodymium fluoride (NdF3) were reported. PA band shifts as compared to their positions in aqueous Nd3+ are used to calculate the nephelauxetic parameters of the compounds. The variation of these parameters and correlation with the nature of metal-ligand bonding were discussed. A novel method is introduced to determine the relative values of oscillator strengths and Judd-Ofelt parameters of powdered samples using PA spectroscopy. It is found that a linear correlation exists between relative values of τ2 and oscillator strengths of hypersensitive transitions of the title compounds. It is hopetul that the new method of PA technique may serve for the Judd-Ofelt quantitative analysis of powdered rare earth compounds.

  13. In Situ and Laboratory Studies on the Fate of Specific Organic Compounds in an Anerobic Landfill Leachate Plume, 2. Fate of Aromatic and Chlorinated Aliphatic Compounds

    DEFF Research Database (Denmark)

    Nielsen, Per Henning; Bjarnadóttir, Helga; Winter, Pia L.

    1995-01-01

    and laboratory batch microcosm experiments performed focusing on redox conditions, microbiology and the fate of 7 phenolic compounds. In this paper we present the results on the fate of 8 aromatic compounds and 4 chlorinated aliphatic compounds. Nitrobenzene was transformed at all distances from the landfill...... the landfill in Fe(IIl)-reducing conditions but not in NO3-reducing conditions at 350 m from the landfill. Abiotic processes apparently contributed to the transformation of tetrachloromethane. A local variation in the transformation of the chlorinated aliphatic hydrocarbons was observed at 2 m from...

  14. Retrospective study of reverse dorsal metacarpal flap and compound flap: a review of 122 cases

    Institute of Scientific and Technical Information of China (English)

    LU Lai-jin; GONG Xu; LIU Zhi-gang; ZHANG Zhi-xin

    2006-01-01

    Objective:To evaluate the clinical application and discuss the operative indication of the reverse dorsal metacarpal flap and its compound flap on the skin defects of hand.Methods: From 1990 to 2003, we applied the reverse dorsal metacarpal flap and its compound flap to repair soft tissue defects of fingers in 122 cases, which included 90cases of the reverse metacarpal flap and 32 cases of its compound flaps with tendon grafts, nerve grafts or bone grafts. Based on the follow-up observations, we analyzed the indications of the reverse metacarpal flap and its compound flaps, the postoperative contours, flap colors and textures in comparison to contralateral fingers retrospectively.Results: In the series of 122 cases, flaps survived and the donor site defects were closed directly. The follow-up period ranged from 1-12 years. The postoperative contours,colors and textures of the flaps and its compound flaps were similar to those of normal fingers, although linear scar remained. According to standards of sense recovery(British Medical Research Council, BMRC ), the sense function of the flaps resumed S3 after operation for 1 year.In 10 cases with the tendon defects treated by the flap with tendon grafts, function of flexion-extension of fingers resumed 50%-75% in comparison to the contralateral fingers using the method of measurement of total active motion. In 7 cases with the phalangeal nonunion or bone defects treated by the flap with bone grafts, union occurred after operation for 3 months.Conclusions: To soft tissue defects on fingers with bone or tendon exposure, the reverse metacarpal flap and its compound flap are a better choice for repairing. The range of repairing is up to the distal interphalangeal joint of fingers. The second dorsal metacarpal artery is more consistent and larger as the choice of vascular pedicle, in comparison with other dorsal metacarpal arteries.Postoperative flap color and texture are similar to normal fingers.

  15. Comparative study between reamed versus unreamed interlocking intramedullary nailing in compound fractures of shaft tibia

    Directory of Open Access Journals (Sweden)

    Subhash Puri

    2013-01-01

    Full Text Available Background: Tibia is the commonest bones to sustain open injury because of subcutaneous position. Treatment of open fractures requires simultaneous management of both skeletal and soft tissue injury. Intramedullary nailing with reaming is generally considered to be contraindicated for open fractures tibia, because it damages the endosteal blood supply which will lead to non-union, deep infection. However, recent studies with or without reaming in open fracture tibia shows no influence in healing of fracture. Purpose: To compare the clinical and radiological results of intramedullary interlocking nailing of open fractures of the tibial shaft after reaming versus unreamed medullary canal. Materials and Methods: Between 2008 and 2011, we have treated 40 patients with compound tibia fracture (type I, II, IIIA by simultaneous care of wound and skeletal injury. Primary fixation for fracture stabilization was done by closed intramedullary interlock nailing either reamed or unreamed; the allocation to the two groups made on alternating basis. Wound was managed by thorough debridement with primary/delayed primary closure by suturing, split thickness skin grafting or fasciocutaneous flap cover. Active, non-weight bearing exercises were started from next post-op day. Partial weight bearing after suture removal was started on 12 th day. Further follow-up was done at 6 weeks interval for union. Results: Open fractures of shaft of tibia treated with unreamed/reamed interlocking nailing gave excellent results. In present series, 19 fractures (95% treated by unreamed and 19 (95% fractures treated by reamed technique, united within 6 months of injury. Delay in union was noticed in one patient treated by unreamed technique who had segmental and extensive soft tissue injury and in reamed nailing there was one patient with deep infection, which was treated with antibiotic coated nail. Conclusion: Time to complete union was similar in both groups. Adequate

  16. 15N NMR study of nitrate ion structure and dynamics in hydrotalcite-like compounds

    Science.gov (United States)

    Hou, X.; James, Kirkpatrick R.; Yu, P.; Moore, D.; Kim, Y.

    2000-01-01

    We report here the first nuclear magnetic resonance (NMR) spectroscopic study of the dynamical and structural behavior of nitrate on the surface and in the interlayer of hydrotalcite-like compounds (15NO3--HT). Spectroscopically resolvable surface-absorbed and interlayer NO3- have dramatically different dynamical characteristics. The interlayer nitrate shows a well defined, temperature independent uniaxial chemical shift anisotropy (CS A) powder pattern. It is rigidly held or perhaps undergoes rotation about its threefold axis at all temperatures between -100 ??C and +80 ??C and relative humidities (R.H.) from 0 to 100% at room temperature. For surface nitrate, however, the dynamical behavior depends substantially on temperature and relative humidity. Analysis of the temperature and R.H. dependences of the peak width yields reorieritational frequencies which increase from essentially 0 at -100 ??C to 2.6 ?? 105 Hz at 60 ??C and an activation energy of 12.6 kJ/mol. For example, for samples at R.H. = 33%, the surface nitrate is isotropically mobile at frequencies greater than 105 Hz at room temperature, but it becomes rigid or only rotates on its threefold axis at -100 ??C. For dry samples and samples heated at 200 ??C (R.H. near 0%), the surface nitrate is not isotropically averaged at room temperature. In contrast to our previous results for 35Cl--containing hydrotalcite (35Cl--HT), no NMR detectable structural phase transition is observed for 15NO3--HT. The mobility of interlayer nitrate in HT is intermediate between that of carbonate and chloride.

  17. Long-term studies on the effects of nonvolatile organic compounds on porous media surface areas.

    Science.gov (United States)

    Khachikian, Crist S; Harmon, Thomas C

    2002-01-01

    This paper investigates the long-term behavior of porous media contaminated by nonvolatile organic compounds (NVOC) in terms of specific interfacial surface area. Specifically, a natural sand, Moffett sand (MS), was contaminated with naphthalene and the surface area was measured repeatedly over time using nitrogen adsorption-desorption techniques. A field-contaminated sand affected by lamp-black material (LB) from former manufactured gas plant operations was also studied. Lampblack is a carbonaceous skeleton containing polycyclic aromatic hydrocarbons (PAHs) and other hydrocarbons. It is hypothesized that soils contaminated by these types of chemicals will exhibit significantly less surface area than their clean counterparts. The surface areas for the contaminated MS samples increased toward their clean-MS values during the 700-h aging period, but achieved the clean values only after pentane extraction or heating at 60 degrees C. Heating at 50 degrees C failed to achieve a similar recovery of the clean-MS surface area value. Nonspecific mass loss tracked the increase in surface area as indirect evidence that naphthalene loss was the cause of the surface area increase. For the LB samples, aging at 100 degrees C produced a slight decrease in surface area and mass while aging at 250 degrees C caused the surface area to increase roughly threefold while the mass decreased by approximately 1%. These results suggest that, under moderate heating and over the time scale of this investigation, there is a redistribution of the complex contaminant mixture on the solid matrix. Greater temperatures remove mass more efficiently and therefore exhibited the surface area increase expected in this experiment.

  18. Dissolution kinetics of volatile organic compound vapors in water: An integrated experimental and computational study

    Science.gov (United States)

    Mahmoodlu, Mojtaba G.; Pontedeiro, Elizabeth M.; Pérez Guerrero, Jesús S.; Raoof, Amir; Majid Hassanizadeh, S.; van Genuchten, Martinus Th.

    2017-01-01

    In this study we performed batch experiments to investigate the dissolution kinetics of trichloroethylene (TCE) and toluene vapors in water at room temperature and atmospheric pressure. The batch systems consisted of a water reservoir and a connected headspace, the latter containing a small glass cylinder filled with pure volatile organic compound (VOC). Results showed that air phase concentrations of both TCE and toluene increased relatively quickly to their maximum values and then became constant. We considered subsequent dissolution into both stirred and unstirred water reservoirs. Results of the stirred experiments showed a quick increase in the VOC concentrations with time up to their solubility limit in water. VOC vapor dissolution was found to be independent of pH. In contrast, salinity had a significant effect on the solubility of TCE and toluene vapors. VOC evaporation and vapor dissolution in the stirred water reservoirs followed first-order rate processes. Observed data could be described well using both simplified analytical solutions, which decoupled the VOC dynamics in the air and water phases, as well as using more complete coupled solutions. However, the estimated evaporation (ke) and dissolution (kd) rate constants differed by up to 70% between the coupled and uncoupled formulations. We also numerically investigated the effects of fluid withdrawal from the small water reservoir due to sampling. While decoupling the VOC air and water phase mass transfer processes produced unreliable estimates of kd, the effects of fluid withdrawal on the estimated rate constants were found to be less important. The unstirred experiments showed a much slower increase in the dissolved VOC concentrations versus time. Molecular diffusion of the VOCs within the aqueous phase became then the limiting factor for mass transfer from air to water. Fluid withdrawal during sampling likely caused some minor convection within the reservoir, which was simulated by increasing the

  19. Atomic jump frequencies in intermetallic compounds studied using perturbed angular correlation of gamma rays

    Science.gov (United States)

    Newhouse, Randal Leslie

    Atomic jump frequencies were determined in a variety of intermetallic compounds through analysis of nuclear relaxation of spectra measured using the nuclear hyperfine technique, perturbed angular correlation (PAC) of gamma rays. Observed at higher temperatures, this relaxation is attributed to fluctuations in the orientation or magnitude of electric field gradients (EFG) at nuclei of 111In/Cd probe atoms as the atoms make diffusive jumps. Jump frequencies were obtained by fitting dynamically relaxed PAC spectra using either an empirical relaxation function or using ab initio relaxation models created using the program PolyPacFit. Jump frequency activation enthalpies were determined from measurements over a range of temperatures. Diffusion was studied in the following systems: 1) Pseudo-binary alloys having the L12 crystal structure such as In3(La1-xPrx). The goal was to see how jump frequencies were affected by random disorder. 2) The family of layered phases, LanCoIn3n+2 ( n=0,1,2,3…∞). The goal was to see how jump frequencies varied with the spacing of Co layers, which were found to block diffusion. 3) Phases having the FeGa3 structure. The goal was to analyze dynamical relaxation for probe atoms having multiple inequivalent jump vectors. 4) Phases having the tetragonal Al4Ba structure. The goal was to search for effects in the PAC spectra caused by fluctuations in magnitudes of EFGs without fluctuations in orientations. Ab initio relaxation models were developed to simulate and fit dynamical relaxation for PAC spectra of FeGa3, and several phases with the Al4Ba structure in order to determine underlying microscopic jump frequencies. In the course of this work, site preferences also were observed for 111In/Cd probe atoms in several FeGa 3 and Al4Ba phases.

  20. Correlation between structural studies and third order NLO properties of selected new quinolinium semi-organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Bouchouit, K., E-mail: karim.bouchouit@laposte.net [Departement de Chimie, Faculte des Sciences, Universite de Jijel (Algeria); Bendeif, E.E. [Laboratoire de Cristallographie, Resonance Magnetique et Modelisation CRM2 CNRS UMR 7036, Institut Jean Barriol, Nancy Universite, Faculte des Sciences, BP 239, 54506 Vandoeuvre-les-Nancy, CEDEX (France); EL Ouazzani, H. [Institut des Sciences et Technologies Moleculaires d' Angers UMR CNRS 6200 MOLTECH ANJOU, Universite d' Angers 2, Boulevard Lavoisier, 49045 Angers (France); Dahaoui, S.; Lecomte, C. [Laboratoire de Cristallographie, Resonance Magnetique et Modelisation CRM2 CNRS UMR 7036, Institut Jean Barriol, Nancy Universite, Faculte des Sciences, BP 239, 54506 Vandoeuvre-les-Nancy, CEDEX (France); Benali-cherif, N. [Laboratoire des Structures, Proprietes et Interactions Inter Atomiques (LASPI2A), Centre Universitaire de Khenchela, 40000 Khenchela (Algeria); Sahraoui, B. [Institut des Sciences et Technologies Moleculaires d' Angers UMR CNRS 6200 MOLTECH ANJOU, Universite d' Angers 2, Boulevard Lavoisier, 49045 Angers (France)

    2010-09-14

    Graphical abstract: Organic quinolinium moieties build a zigzag layers in compounds (II) - Abstract: New quinolinium semi-organic compounds of formula (C{sub 9}H{sub 8}N){sub 2}{sup +}.SO{sub 4}{sup 2-},H{sub 2}O (I) (bis-quinolinium sulphate monohydrate) and (C{sub 9}H{sub 8}N){sup +}.NO{sub 3}{sup -} (II) (quinolinium nitrate) have been synthesized and characterized by UV-Vis absorption spectroscopy, nonlinear optical (NLO) measurements and by single crystal X-ray diffraction. The third order nonlinear optical properties of (I) and (II) were investigated using two methods: the degenerate four wave mixing technique (DFWM) performed in solution at {lambda} = 532 nm and the third-harmonic generation (THG) measurements carried out on thin films at {lambda} = 1064 nm. The NLO measurements showed that compound (I) presents better nonlinear optical properties compared to compound (II). To understand further the optical behaviour of (I) and (II), the crystal structures of both compounds were determined from accurate single crystal X-ray diffraction measurements performed at 100 K. The crystallographic studies revealed the key role of the intermolecular interactions and the molecular arrangements in the enhancement of the NLO properties.

  1. DFT studies on a high energy density cage compound 4-trinitroethyl-2,6,8,10,12-pentanitrohezaazaisowurtzitane.

    Science.gov (United States)

    Zhang, Jian-ying; Du, Hong-chen; Wang, Fang; Gong, Xue-dong; Huang, Yin-sheng

    2011-06-23

    Polynitro cage compound 4-trinitroethyl-2,6,8,10,12-pentanitrohexaazaisowurtzitane has the same framework with but higher stability than CL-20 and is a potential new high energy density compound (HEDC). In this paper, the B3LYP/6-31G(d,p) method of density functional theory (DFT) has been used to study its heat of formation, IR spectrum, and thermodynamic properties. The stability of the compound was evaluated by the bond dissociation energies. The calculated results show that the first step of pyrolysis is the rupture of the N-NO(2) bond in the side chain and verify the experimental observation that the title compound has better stability than CL-20. The crystal structure obtained by molecular mechanics belongs to the P2(1)2(1)2(1) space group, with lattice parameters a = 12.59 Å, b = 10.52 Å, c = 12.89 Å, Z = 4, and ρ = 2.165 g·cm(-3). Both the detonation velocity of 9.767 km·s(-1) and the detonation pressure of 45.191 GPa estimated using the Kamlet-Jacobs equation are better than those of CL-20. Considering that this cage compound has a better detonation performance and stability than CL-20, it may be a superior HEDC.

  2. Blood shizonticidal activities of phenazines and naphthoquinoidal compounds against Plasmodium falciparum in vitro and in mice malaria studies

    Directory of Open Access Journals (Sweden)

    Nicolli Bellotti de Souza

    2014-08-01

    Full Text Available Due to the recent advances of atovaquone, a naphthoquinone, through clinical trials as treatment for malarial infection, 19 quinone derivatives with previously reported structures were also evaluated for blood schizonticide activity against the malaria parasite Plasmodium falciparum. These compounds include 2-hydroxy-3-methylamino naphthoquinones (2-9, lapachol (10, nor-lapachol (11, iso-lapachol (12, phthiocol (13 and phenazines (12-20. Their cytotoxicities were also evaluated against human hepatoma and normal monkey kidney cell lines. Compounds 2 and 5 showed the highest activity against P. falciparum chloroquine-resistant blood-stage parasites (clone W2, indicated by their low inhibitory concentration for 50% (IC50 of parasite growth. The therapeutic potential of the active compounds was evaluated according to the selectivity index, which is a ratio of the cytotoxicity minimum lethal dose which eliminates 50% of cells and the in vitro IC50. Naphthoquinones 2 and 5, with activities similar to the reference antimalarial chloroquine, were also active against malaria in mice and suppressed parasitaemia by more than 60% in contrast to compound 11 which was inactive. Based on their in vitro and in vivo activities, compounds 2 and 5 are considered promising molecules for antimalarial treatment and warrant further study.

  3. 定心藤中酚性成分的研究%Study of phenolic compounds from Mappianthus iodoies

    Institute of Scientific and Technical Information of China (English)

    曾立; 尹文清

    2011-01-01

    Objective: Study the phenolic compounds from Mappianthus iodoies. Methods: The column of silica gel was employed for the isolation and purification of the phenolic compounds,the structures of the compounds were identified by physiochemical properties and spectral analysis. Results: Six phenolic compounds were isolated from Mappianthus iodoies,Their structures were determined by spectroscopic analysis to be vanillin sinomenine(Ⅰ), Vanillin(Ⅱ), chrysin(Ⅲ), vanillic acid (Ⅳ),quercetin(Ⅴ), gallic acid(Ⅵ). Conclusion: All compounds were first reported from this plant.%目的:研究定心藤中酚性成分.方法:用色谱技术进行分离,波谱法进行鉴定.结果:从定心藤中分离得到6个酚性化合物,依次鉴定为青藤碱(I)、香草醛(Ⅱ)、白杨素(Ⅲ)、香草酸(Ⅳ)、槲皮素(Ⅴ)、没食子酸(Ⅵ).结论:所有化合物均首次从该植物中分离得到.

  4. PHYTOCHEMICAL STUDY AND EVALUATION OF THE ANTIMICROBIAL AND ANTIOXIDANT ACTIVITY OF ESSENTIAL OILS AND PHENOLIC COMPOUNDS OF PISTACIA LENTISCUS L

    OpenAIRE

    K. Arab; O. Bouchenak; K. Yahiaoui

    2014-01-01

    This work aims for the phytochemical study and evaluation of the antioxidant activity of phenolic compounds and essential oils of medicinal plant Pistacia lentiscus L. quantitatively and qualitatively. Through the results obtained, it appears that the leaves and fruits are rich in substances with a high antioxidant power. The yield of the phenolic compounds obtained from 10g  to powder of plant  is for leaves 116.49 %  and 61.34 % for fruit . For essential oils, it is 0.253 ± 0.131 % for 100 ...

  5. Study of antioxidant property of a thiosphosphorated compound derived from cashew nut shell liquid in hydrogenated naphthenics oils

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, A.A.S.; Carneiro, E.A. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Quimica]. E-mail: adasanders@gmail.com; Rios, M.A.S.; Hiluy Filho, J.J.; Carioca, J.O.B.; Barros, G.G.; Mazzetto, S.E. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Parque de Desenvolvimento Tecnologico

    2008-01-15

    The present work shows the aspects related to the synthesis and thermogravimetric analysis of thiophosphorated and phosphorated compounds from hydrogenated cardanol. Studies on thermal-oxidative stability were investigated, using a classical thermoanalytical-thermogravimetric method (TG/DTG) in an air atmosphere. Its use as an antioxidant additive in hydrogenated naphthenic NH10, NH20 and NH140 oils was evaluated. The addition of 1.2% synthesized compounds to the oils has improved their thermal-oxidative stability by 5-15 deg C. The occurrence of major thermal degradation events at higher temperatures (T{sub max}) in additivated oils is a good indication of the antioxidant properties of the thiophosphorated and phosphorated cardanol compounds antioxidant properties. (author)

  6. Study of antioxidant property of a thiosphorated compound derived from cashew nut shell liquid in hydrogenated naphthenics oils

    Directory of Open Access Journals (Sweden)

    A. A. S. Lopes

    2008-03-01

    Full Text Available The present work shows the aspects related to the synthesis and thermogravimetric analysis of thiophosphorated and phosphorated compounds from hydrogenated cardanol. Studies on thermal-oxidative stability were investigated, using a classical thermoanalytical-thermogravimetric method (TG/DTG in an air atmosphere. Its use as an antioxidant additive in hydrogenated naphthenic NH10, NH20 and NH140 oils was evaluated. The addition of 1.2% synthesized compounds to the oils has improved their thermal-oxidative stability by 5-15ºC. The occurrence of major thermal degradation events at higher temperatures (Tmax in additivated oils is a good indication of the antioxidant properties of the thiophosphorated and phosphorated cardanol compounds antioxidant properties.

  7. A Comparative Study of the Electronic and Magnetic Properties of Gd5Ge4 and Gd5Si4 Compounds

    Science.gov (United States)

    Z. Momeni, Larimi; Amirabadizadeh, A.; Yazdani, A.; Arabi, H.

    2014-12-01

    We present a comparative study of electronic structure and magnetic properties of Gd5Si4 and Gd5Ge4 compounds using first principles full potential linearized augmented plane wave (FP-LAPW) method based on density functional theory (DFT) using the WIEN2k code. The local-spin density approximation with correlation energy (LSDA+U) method has been used as the exchange-correlation potential. The optimized lattice constants are in good agreement with the experimental data. The total and partial density of states (DOS) of Gd5Si4 and Gd5Ge4 show the difference in Si 3p-Gd 5d and Ge 4p-Gd 5d hybridization, which have an effective role in indirect exchange interaction. In addition, the magnetic moments of Gd, Si, and Ge atoms and the compounds are calculated to clarify the differences in the magnetic properties of these compounds.

  8. A quantum chemical based toxicity study of estimated reduction potential and hydrophobicity in series of nitroaromatic compounds.

    Science.gov (United States)

    Gooch, A; Sizochenko, N; Sviatenko, L; Gorb, L; Leszczynski, J

    2017-02-01

    Nitroaromatic compounds and the products of their degradation are toxic to bacteria, cells and animals. Various studies have been carried out to better understand the mechanism of toxicity of aromatic nitrocompounds and their relationship to humans and the environment. Recent data relate cytotoxicity of nitroaromatic compounds to their single- or two-electron enzymatic reduction. However, mechanisms of animal toxicity could be more complex. This work investigates the estimated reduction and oxidation potentials of 34 nitroaromatic compounds using quantum chemical approaches. All geometries were optimized with density functional theory (DFT) using the solvation model based on density (SMD) and polarizable continuum model (PCM) solvent model protocols. Quantitative structure-activity/property (QSAR/QSPR) models were developed using descriptors obtained from quantum chemical optimizations as well as the DRAGON software program. The QSAR/QSPR equations developed consist of two to four descriptors. Correlations have been identified between electron affinity (ELUMO) and hydrophobicity (log P).

  9. PHYTOCHEMICAL STUDY AND EVALUATION OF THE ANTIMICROBIAL AND ANTIOXIDANT ACTIVITY OF ESSENTIAL OILS AND PHENOLIC COMPOUNDS OF PISTACIA LENTISCUS L

    Directory of Open Access Journals (Sweden)

    K. Arab

    2015-07-01

    Full Text Available This work aims for the phytochemical study and evaluation of the antioxidant activity of phenolic compounds and essential oils of medicinal plant Pistacia lentiscus L. quantitatively and qualitatively. Through the results obtained, it appears that the leaves and fruits are rich in substances with a high antioxidant power. The yield of the phenolic compounds obtained from 10g  to powder of plant  is for leaves 116.49 %  and 61.34 % for fruit . For essential oils, it is 0.253 ± 0.131 % for 100 g of plant material. The chromatographic profile of the essential oil of Pistacia lentiscus L. shows that monoterpenes are the major compound (9.675 % of identified molecules. The strong antioxidant activity of extracts obtained only confirms the traditional use of this plant by the local population.

  10. PHYTOCHEMICAL STUDY AND EVALUATION OF THE ANTIMICROBIAL AND ANTIOXIDANT ACTIVITY OF ESSENTIAL OILS AND PHENOLIC COMPOUNDS OF PISTACIA LENTISCUS L

    Directory of Open Access Journals (Sweden)

    K. Arab

    2014-06-01

    Full Text Available This work aims for the phytochemical study and evaluation of the antioxidant activity of phenolic compounds and essential oils of medicinal plant Pistacia lentiscus L. quantitatively and qualitatively. Through the results obtained, it appears that the leaves and fruits are rich in substances with a high antioxidant power. The yield of the phenolic compounds obtained from 10g to powder of plant is for leaves 116.49 % and 61.34 % for fruit . For essential oils, it is 0.253 ± 0.131 % for 100 g of plant material. The chromatographic profile of the essential oil of Pistacia lentiscus L. shows that monoterpenes are the major compound (9.675 % of identified molecules. The strong antioxidant activity of extracts obtained only confirms the traditional use of this plant by the local population.

  11. Growth of Compounding Awareness Predicts Reading Comprehension in Young Chinese Students: A Longitudinal Study from Grade 1 to Grade 2

    Science.gov (United States)

    Cheng, Yahua; Zhang, Jie; Li, Hong; Wu, Xinchun; Liu, Hongyun; Dong, Qiong; Li, Liping; Nguyen, Thi Phuong; Zheng, Minglu; Zhao, Ying; Sun, Peng

    2017-01-01

    Using a longitudinal sample of young Chinese students (fall and spring in grades 1 and 2: times 1-4, respectively) and growth curve analysis, this study examined whether the initial status and growth rates of compounding awareness from time 1 to time 4 uniquely contribute to reading comprehension at time 4 and whether word-reading efficiency at…

  12. Studies on the quantitative structure-activity relationship of the inhibition of xanthine oxidase by azaheterocyclic compounds.

    NARCIS (Netherlands)

    Naeff, H.S.D.

    1990-01-01

    This thesis contains the results of a QSAR analysis of the interaction of bovine milk xanthine oxidase with two azaheterocyclic compounds, namely the 6-arylpteridin- 4-ones and the 8-arylhypoxanthines. Xanthine oxidase has active sites for various substrates. The studies done for this thesis were of

  13. Growth of Compounding Awareness Predicts Reading Comprehension in Young Chinese Students: A Longitudinal Study from Grade 1 to Grade 2

    Science.gov (United States)

    Cheng, Yahua; Zhang, Jie; Li, Hong; Wu, Xinchun; Liu, Hongyun; Dong, Qiong; Li, Liping; Nguyen, Thi Phuong; Zheng, Minglu; Zhao, Ying; Sun, Peng

    2017-01-01

    Using a longitudinal sample of young Chinese students (fall and spring in grades 1 and 2: times 1-4, respectively) and growth curve analysis, this study examined whether the initial status and growth rates of compounding awareness from time 1 to time 4 uniquely contribute to reading comprehension at time 4 and whether word-reading efficiency at…

  14. A Singlet Oxygen Photogeneration and Luminescence Study of Unsymmetrically Substituted Mesoporphyrinic Compounds

    Directory of Open Access Journals (Sweden)

    Anabela Sousa Oliveira

    2009-01-01

    Full Text Available This paper deals with a series of new unsymmetrically substituted mesoporphyrins: 5-(2-hydroxyphenyl-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHO, 5-(3-hydroxyphenyl-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHM, 5-(4-hydroxyphenyl-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHP, 5-(2-hydroxyphenyl-10,15,20-tris-butyl-21,23-H-porphyrin (TBPOHO, and their parent nonsubstituted compounds, respectively, 5,10,15,20-tetrakis-phenyl-21,23-H-porphyrin (TPP and 5,10,15,20-tetrakis-butyl-21,23-H-porphyrin (TBP. Several photophysical studies were carried out to access the influence of the unsymmetrical substitution at the porphyrinic macrocycle on porthyrin's photophysical properties, especially porthyrin's efficiency as singlet oxygen sensitizers. The quantum yields of singlet oxygen generation were determined in benzene (ΦΔ(TPP = 0.66 ± 0.05; ΦΔ(TPPOHO = 0.69 ± 0.04; ΦΔ(TPPOHM = 0.62 ± 0.04; ΦΔ(TPPOHP = 0.73 ± 0.03; ΦΔ(TBP = 0.76 ± 0.03; ΦΔ(TBPOHO = 0.73 ± 0.02 using the 5,10,15,20-tetraphenyl-21,23-H-porphine (ΦΔ(TPP = 0.66 and Phenazine (ΦΔ(Phz = 0.83 as reference compounds. Their fluorescence quantum yields were found to be (Φf(TPPOHO = 0.10 ± 0.04; Φf(TPPOHM = 0.09 ± 0.03; Φf(TPPOHP = 0.13 ± 0.02; Φf(TBP = 0.08 ± 0.03 and Φf(TBPOHO = 0.08 ± 0.02 using 5,10,15,20-tetraphenyl-21,23-H-porphine as reference Φf(TPP = 0.13. Singlet state lifetimes were also determined in the same solvent. All the porphyrins presented very similar fluorescence lifetimes (mean values of τS (with O2, air equilibrated = 9.6 ± 0.3 nanoseconds and (without O2, argon purged = 10.1 ± 0.6 nanoseconds, resp.. The phosphorescence emission was found to be negligible for this series of unsymmetrically substituted mesoporphyrins, but an E-type, thermally activated, delayed fluorescence process was proved to occur at room temperature.

  15. Ab initio study on structures and stabilities of OLi_nhyperlithiated compounds

    Institute of Scientific and Technical Information of China (English)

    郑祥娥; 王志中; 唐敖庆

    1999-01-01

    The geometries of hyperlithiated compounds OLin were optimized by means of HF, MP2 and DFT methods with 6-31G basis set. The dissociation energies of those optimized stable geometries of OLin were calculated, the results are in good agreement with experimental values; and moreover, the dissociation energy of OLi6 is predicted. In addition, the fundamental vibrational frequencies were also predicted.

  16. Absorption tuning of the green fluorescent protein chromophore: synthesis and studies of model compounds

    DEFF Research Database (Denmark)

    Brøndsted Nielsen, Mogens; Andersen, Lars Henrik; Rinza, Tomás Rocha

    2011-01-01

    The green fluorescent protein (GFP) chromophore is a heterocyclic compound containing a p-hydroxybenzylidine attached to an imidazol-5(4H)-one ring. This review covers the synthesis of a variety of model systems for elucidating the intrinsic optical properties of the chromophore in the gas phase...

  17. [Progress in study of flavonoids from Annonaceae and biological activities of these compounds].

    Science.gov (United States)

    Hu, Chun-Mei; Wu, Jiu-Hong

    2007-05-01

    More than 50 new flavonoids derived from Annonaceae are reported in the last two decades. Many genuses in Annonaceae contain flavonoids having structural novelty and broad pharmacological activities. Due to the pharmacological interest of some of these compounds, chemical investigations on this topic have grown considerably in the decades. Here the biological activities of some of these flavonoids are also briefly discussed.

  18. Search for new scintillators by studying the fluorescence properties of powdered compounds with synchrotron radiation.

    Science.gov (United States)

    Dewu, W; Jianfei, L; Yaning, X; Yifan, G; Yu, C; Hancheng, S; Jiashan, Z; Zuqi, Z

    1995-03-01

    This paper describes a method for investigating the properties of powdered compounds using synchrotron X-radiation. The fluorescence decay times of bismuth germanate, BaF(2), CeF(3) and CsI, as well as the light yields of several samples of gadolinium silicate, prepared in different ways, have been measured.

  19. GENETIC STUDIES ON TRIPTERYGIUM WILFORDII--AN ACTIVE COMPOUND ISOLATED FROM THE PLANT

    Institute of Scientific and Technical Information of China (English)

    SillJia-Fang; WANGYi; LIUQi-Lan; PANLi; SUNJia-Qing; ZI-IANGZhu-Tao; HUYanZhong; XUYe; QIANShao-Zhen

    1989-01-01

    The multiglycosides ofTriptcrygium wilfordii Hook. f(GTW), a Chinese herbal medicine used for the treatment of certain diseases, has been shown to cause reversible infertility both in male rats and in men. Very recently, we Found that an active compound (T4)

  20. Exhaled volatile organic compounds for phenotyping chronic obstructive pulmonary disease: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Basanta Maria

    2012-08-01

    Full Text Available Abstract Background Non-invasive phenotyping of chronic respiratory diseases would be highly beneficial in the personalised medicine of the future. Volatile organic compounds can be measured in the exhaled breath and may be produced or altered by disease processes. We investigated whether distinct patterns of these compounds were present in chronic obstructive pulmonary disease (COPD and clinically relevant disease phenotypes. Methods Breath samples from 39 COPD subjects and 32 healthy controls were collected and analysed using gas chromatography time-of-flight mass spectrometry. Subjects with COPD also underwent sputum induction. Discriminatory compounds were identified by univariate logistic regression followed by multivariate analysis: 1. principal component analysis; 2. multivariate logistic regression; 3. receiver operating characteristic (ROC analysis. Results Comparing COPD versus healthy controls, principal component analysis clustered the 20 best-discriminating compounds into four components explaining 71% of the variance. Multivariate logistic regression constructed an optimised model using two components with an accuracy of 69%. The model had 85% sensitivity, 50% specificity and ROC area under the curve of 0.74. Analysis of COPD subgroups showed the method could classify COPD subjects with far greater accuracy. Models were constructed which classified subjects with ≥2% sputum eosinophilia with ROC area under the curve of 0.94 and those having frequent exacerbations 0.95. Potential biomarkers correlated to clinical variables were identified in each subgroup. Conclusion The exhaled breath volatile organic compound profile discriminated between COPD and healthy controls and identified clinically relevant COPD subgroups. If these findings are validated in prospective cohorts, they may have diagnostic and management value in this disease.

  1. Bonding in inorganic compounds: a study by x-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Avanzino, S.C.

    1978-10-01

    Core electron binding energies were measured for a variety of inorganic and organometallic compounds using gas-phase X-ray photoelectron spectroscopy (XPS). The atomic charge distributions in these molecules are deduced from the binding energies, often leading to a better understanding of the bonding in these compounds. The XPS spectra of fifteen volatile tin compounds were recorded. The data suggest that the metal d orbitals are not significantly involved in the bonding. The oxygen ls XPS spectra of gaseous CH/sub 3/Mn(CO)/sub 5/, (..pi..-C/sub 5/H/sub 5/Fe(CO)/sub 2/)/sub 2/, and Co/sub 4/(CO)/sub 12/ can be readily resolved into separate peaks due to bridging and terminal carbonyl groups. The C ls spectrum of Fe(CO)/sub 5/ consists of a single symmetric peak. The carbonyl ligand core binding energies of transition-metal carbonyl complexes are sensitive to differences in the metal-to-CO ligand bonding. Both C ls and O ls carbonyl binding energies correlate well with average C-O stretching force constants or average C-O stretching frequencies. The metal and carbonyl binding energies in a series of pentacarbonylmanganese complexes LMn(CO)/sub 5/ are a good measure of the relative electronegativities of the ligands L. High-quality X-ray photoelectron spectra have been obtained for compounds dissolved in glycerin solutions, and aqueous solutions were converted into glycerin solutions which gave good XRSspectra of the solutes. The technique appears promising as a future analytical application of X-ray photoelectron spectroscopy. The shifts in the binding energies of oxygen, chlorine, and carbon atoms in some isoelectronic isostructural compounds can be explained in terms of simple trends in atomic charges.

  2. Study on the recycling of waste PVC compounds from electrical wires

    Energy Technology Data Exchange (ETDEWEB)

    Roman Jr, Celso, E-mail: romancelso@gmail.com; Zattera, Ademir José, E-mail: romancelso@gmail.com [Center for Exact Sciences and Technology (CCET), University of Caxias do Sul (UCS), Caxias do Sul-RS (Brazil)

    2014-05-15

    The good mechanical, thermal and electrical properties of poly (vinyl chloride) (PVC) make it a polymer used in many applications, among which is the coating of wires and cables. The processing of PVC for this application is made using the extrusion process. The PVC waste resulting from extrusion can be recycled or placed on landfills. The objective of this work is to develop recycling methods to decrease the amount of PVC stored in landfills. This work evaluated the influence of successive processing of PVC on the final properties of the obtained compound, which will be used in the process of coating wire and cable by extrusion. The mechanical properties of the electrical wires were assessed according to the Brazilian Association of Technical Standards (ABNT NBR 6251). Tests of tensile strength, elongation at break, before and after thermal aging in an oven with air circulation for a period of 168 hours at 100 °C were performed. The degradation of the PVC compound was carried out through Fourier transform infrared spectroscopy (FTIR) and mechanical properties evaluation. The results showed that the compound can be reprocessed five times keeping the minimum requirements of the ABNT NBR 6251 Standard. Reprocessing was stopped upon color changing (yellowing) of the compound. Yellowing is a characteristic degradation behavior by dehydrochlorination of PVC. FTIR analysis showed changes at 1600 cm{sup −1}, 1430 cm{sup −1}, 685 cm{sup −1} and 614 cm{sup −1} bands. The performance of the PVC compound for coating electrical wire and cable was fair, meeting the requirements of the ABNT NBR 6251 Standard even after five reprocessing cycles.

  3. Improved QSPR Study of Diamagnetic Susceptibilities for Organic Compounds Using Two Novel Molecular Connectivity Indexes

    Institute of Scientific and Technical Information of China (English)

    MU Lailong; HE Hongmei; YANG Weihua

    2009-01-01

    For predicting the molar diamagnetic susceptibilities of organic compounds, a variable molecular connectivity index mχ' and its converse index mχ" based on adjacency matrix of molecular graphs and the variable atomic valence connectivity index δi' were proposed. The optimal values of parameters x, a, and y included in definition of δi', mχ' and mχ" can be found by an optimization method. When x=2.9, a= 1.10, and y=0.36, a good five-parameter model for the molar diamagnetic susceptibilities can be constructed from 0χ',1χ',2χ',1χ" and 2χ" by using the best subset re-gression analysis method. The correlation coefficient r, standard error s, and average absolute deviation of the mul-tilinear regression (MLR) model are 0.9930, 4.96 cgs, and 3.74 cgs, respectively, for the 721 organic compounds (training set). The cross-validation by using the leave-one-out method demonstrates that the MLR model is highly reliable from the point of view of statistics. The average absolute deviation of predicted values of the molar dia-magnetic susceptibility of another 360 organic compounds (test set) is 4.37 cgs for the MLR model. The results show that the current method is more effective than literature methods for estimating the molar diamagnetic suscep-tibility of an organic compound. The MLR method can provide an acceptable model for the prediction of the molar diamagnetic susceptibilities of organic compounds.

  4. The solvent-extractable organic compounds in the Indonesia biomass burning aerosols - characterization studies

    Science.gov (United States)

    Fang, M.; Zheng, M.; Wang, F.; To, K. L.; Jaafar, A. B.; Tong, S. L.

    The large-scale air pollution episode due to the out-of-control biomass burning for agricultural purposes in Indonesia started in June 1997, has become a severe environmental problem for itself and the neighboring countries. The fire lasted for almost five months. Its impact on the health and ecology in the affected areas is expected to be substantial, costly and possibly long lasting. Air pollution Index as high as 839 has been reported in Malaysia. API is calculated based on the five pollutants: NO 2, SO 2, O 3, CO, and respirable suspended particulates (PM10). It ranges in value from 0 to 500. An index above 101 is considered to be unhealthy and a value over 201 is very unhealthy (Abidin and Shin, 1996). The solvent-extractable organic compounds from four total suspended particulate (TSP) high-volume samples collected in Kuala Lumpur, Malaysia (Stations Pudu and SIRIM) were subjected to characterization - the abundance was determined and biomarkers were identified. Two of the samples were from early September when the fire was less intense, while the other two were from late September when Kuala Lumpur experienced very heavy smoke coverage which could be easily observed from NOAA/AVHRR satellite images. The samples contained mainly aliphatic hydrocarbons such as n-alkanes and triterpanes, alkanoic acids, alkanols, and polycyclic aromatic hydrocarbons. The difference between the early and late September samples was very significant. The total yield increased from 0.6 to 24.3 μg m -3 at Pudu and 1.9 to 20.1 μg m -3 at SIRIM, with increases in concentration in every class. The higher input of vascular plant wax components in the late September samples, when the fire was more intense, was characterized by the distribution patterns of the homologous series n-alkanes, n-alkanoic acids, and n-alkanols, e.g., lower U : R, higher >C 22/C 20/Abas et al., 1995), the present study also showed an absence of conifer tracers in the smoke aerosols indicating tropical wood

  5. Study of the effect of surfactants on extraction and determination of polyphenolic compounds and antioxidant capacity of fruits extracts.

    Science.gov (United States)

    Hosseinzadeh, Reza; Khorsandi, Khatereh; Hemmaty, Syavash

    2013-01-01

    Micelle/water mixed solutions of different surface active agents were studied for their effectiveness in the extraction of polyphenolic compounds from various varieties of apples from west Azerbaijan province in Iran. The total content of polyphenolic compound in fruit extracts were determined using ferrous tartrate and Folin-Ciocalteu assays methods and chromatographic methods and compared with theme. High performance liquid chromatography is one of the most common and important methods in biochemical compound identification. The effect of pH, ionic strength, surfactant type, surfactant concentration, extraction time and common organic solvent in the apple polyphenolics extractions was studied using HPLC-DAD. Mixtures of surfactants, water and methanol at various ratios were examined and micellar-water solutions of Brij surfactant showed the highest polyphenol extraction efficiency. Optimum conditions for the extraction of polyphenolic compounds from apple occurred at 7 mM Brij35, pH 3. Effect of ionic strength on extraction was determined and 2% (W/V) potassium Chloride was determined to be the optimum salt concentration. The procedure worked well with an ultrasound bath. Total antioxidant capacity also was determined in this study. The method can be safely scaled up for pharmaceutical applications.

  6. Study of the effect of surfactants on extraction and determination of polyphenolic compounds and antioxidant capacity of fruits extracts.

    Directory of Open Access Journals (Sweden)

    Reza Hosseinzadeh

    Full Text Available Micelle/water mixed solutions of different surface active agents were studied for their effectiveness in the extraction of polyphenolic compounds from various varieties of apples from west Azerbaijan province in Iran. The total content of polyphenolic compound in fruit extracts were determined using ferrous tartrate and Folin-Ciocalteu assays methods and chromatographic methods and compared with theme. High performance liquid chromatography is one of the most common and important methods in biochemical compound identification. The effect of pH, ionic strength, surfactant type, surfactant concentration, extraction time and common organic solvent in the apple polyphenolics extractions was studied using HPLC-DAD. Mixtures of surfactants, water and methanol at various ratios were examined and micellar-water solutions of Brij surfactant showed the highest polyphenol extraction efficiency. Optimum conditions for the extraction of polyphenolic compounds from apple occurred at 7 mM Brij35, pH 3. Effect of ionic strength on extraction was determined and 2% (W/V potassium Chloride was determined to be the optimum salt concentration. The procedure worked well with an ultrasound bath. Total antioxidant capacity also was determined in this study. The method can be safely scaled up for pharmaceutical applications.

  7. Study on the presence and influence of phenolic compounds in callogenesis and somatic embryo development of cocoa (Theobroma cacao L..

    Directory of Open Access Journals (Sweden)

    Sulistyani Pancaningtyas

    2015-03-01

    Full Text Available Cocoa (Theobroma cacao L. like most tropical trees is recalcitrant in tissue culture. Somatic embryogenesis is generally efficient micropropagation technique to multiply elite material. However, Somatic embryogenesis in cocoa is difficult and this species is considered as recalcitrant. One of the factors often considered as a component of in vitro recalsitrance is a high phenolic content and oxidation of these compounds. In cocoa tissue culture accumulate large amounts of poliphenolics compounds which probably impair further development. This study was conducted to investigate the composition of phenolic compounds in cocoa flower and leaves, and their changes troughout the somatic embryogenesis process. Calli were induced in cacao floral and leaves explants on a half-strenght Murashige and Skoog medium containing 30 g/L Glucose and combination of 2,4 dichlorophenoxyacetic acid (2,4 D with kinetin (kin. Total polyphenol content was observed on Sulawesi 1 cocoa clone. Embryogenic and non-embryogenic callus were also compared. The percentage of callus production from flower tissue is 85%, percentage of embryogenic callus 40 %, although  the percentage of somatic embryo production from embryogenic callus callus is 70%. The conservation of callus into somatic embryos followed by decline in phenol content and an increase in peroxidase. The synthesis kinetics for these compounds in calli, under different somatic embryogenesis conditions, revealed a higher concentration under non-embryogenic conditions. So that, phenolic compound can influence the production of calli and an absence the phenolic compound can enhance production of somatic embryo.Kata kunci: Theobroma cacao L., polifenol, embrio somatik, kalus, flavonoid, katekin, in vitro recalcitance

  8. Occurrence of 13 volatile organic compounds in foods from the Canadian total diet study.

    Science.gov (United States)

    Cao, Xu-Liang; Sparling, Melissa; Dabeka, Robert

    2016-01-01

    Volatile organic compounds (VOCs) are ubiquitous in the environment due to evaporation and incomplete combustion of fuels, use of consumer and personal care products, etc. and they can accumulate in foods. Some VOCs in foods can also be formed during food processing and preparation and migrate from food packaging. In this pilot study, a GC-MS method based on headspace solid-phase microextraction (SPME) was validated and used to analyse selected individual foods which can be consumed directly and 153 different total diet composite food samples for 13 VOCs. Vinyl chloride was not detected in any of the 153 composite food samples, while the other 12 VOCs were detected at various frequencies, with m-xylene being the most frequently detected (in 151 of the 153 samples), followed by toluene (145), 1,3,5-trimethylbenzene (140), ethylbenzene (139), styrene (133), 1,2,4-trimethylbenzene (122), benzene (96), p-dichlorobenzene (95), n-butylbenzene (55), chloroform (45), naphthalene (45) and trichloroethylene (31). Concentrations of the 12 VOCs in most of the food composite samples were low, with the 90th percentiles from 1.6 ng g(-1) for n-butylbenzene to 20 ng g(-1) for toluene. However, some VOCs were detected at higher levels with maxima, for example, of 948 ng g(-1) for m-xylene and 320 ng g(-1) for ethylbenzene in chewing gum, 207 ng g(-1) for styrene and 157 ng g(-1) for toluene in herbs and spices. VOCs were detected at higher levels in most of the individual food items than their corresponding composite samples, for example, the average chloroform concentration in the individual canned soft drinks was 20 ng g(-1) compared with 3.0 ng g(-1) in their composite, and the average toluene concentration in the individual canned citrus juice was 96 ng g(-1) compared with 0.68 ng g(-1) in their composite. Thus, for determination of VOCs in foods which can be consumed directly, their individual food items should be analysed whenever possible for accurate

  9. Immune function biomarkers in children exposed to lead and organochlorine compounds: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Obi-Osius Nadia

    2005-04-01

    Full Text Available Abstract Background Different organochlorines and lead (Pb have been shown to have immunomodulating properties. Children are at greater risk for exposure to these environmental toxicants, but very little data exist on simultaneous exposures to these substances. Methods We investigated whether the organochlorine compounds (OC dichlorodiphenylethylene (DDE, hexachlorobenzene (HCB, hexachlorocyclohexane (γ-HCH, the sum of polychlorinated biphenyls (ΣPCBs and Pb were associated with immune markers such as immunoglobulin (Ig levels, white blood cell (WBC, counts of lymphocytes; eosinophils and their eosinophilic granula as well as IgE count on basophils. The investigation was part of a cross-sectional environmental study in Hesse, Germany. In 1995, exposure to OC and Pb were determined, questionnaire data collected and immune markers quantified in 331 children. For the analyses, exposure (OC and Pb concentrations were grouped in quartiles (γ-HCH into tertiles. Using linear regression, controlling for age, gender, passive smoking, serum lipids, and infections in the previous 12 months, we assessed the association between exposures and immune markers. Adjusted geometric means are provided for the different exposure levels. Results Geometric means were: DDE 0.32 μg/L, ΣPCBs 0.50 μg/L, HCB 0.22 μg/L, γ-HCH 0.02 μg/L and Pb 26.8 μg/L. The ΣPCBs was significantly associated with increased IgM levels, whereas HCB was inversely related to IgM. There was a higher number of NK cells (CD56+ with increased γ-HCH concentrations. At higher lead concentrations we saw increased IgE levels. DDE showed the most associations with significant increases in WBC count, in IgE count on basophils, IgE, IgG, and IgA levels. DDE was also found to significantly decrease eosinophilic granula content. Conclusion Low-level exposures to OC and lead (Pb in children may have immunomodulating effects. The increased IgE levels, IgE count on basophils, and the reduction of

  10. Wild Roman chamomile extracts and phenolic compounds: enzymatic assays and molecular modelling studies with VEGFR-2 tyrosine kinase.

    Science.gov (United States)

    Guimarães, Rafaela; Calhelha, Ricardo C; Froufe, Hugo J C; Abreu, Rui M V; Carvalho, Ana Maria; Queiroz, Maria João R P; Ferreira, Isabel C F R

    2016-01-01

    Angiogenesis is a process by which new blood vessels are formed from the pre-existing vasculature, and it is a key process that leads to tumour development. Some studies have recognized phenolic compounds as chemopreventive agents; flavonoids, in particular, seem to suppress the growth of tumor cells modifying the cell cycle. Herein, the antiangiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and the main phenolic compounds present (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, and luteolin-7-O-glucoside) was evaluated through enzymatic assays using the tyrosine kinase intracellular domain of the Vascular Endothelium Growth Factor Receptor-2 (VEGFR-2), which is a transmembrane receptor expressed fundamentally in endothelial cells involved in angiogenesis, and molecular modelling studies. The methanolic extract showed a lower IC50 value (concentration that provided 50% of VEGFR-2 inhibition) than the infusion, 269 and 301 μg mL(-1), respectively. Regarding phenolic compounds, luteolin and apigenin showed the highest capacity to inhibit the phosphorylation of VEGFR-2, leading us to believe that these compounds are involved in the activity revealed by the methanolic extract.

  11. Synthesis of hydantoin and thiohydantoin related compounds from benzil and study of their cytotoxicity

    Directory of Open Access Journals (Sweden)

    A. Kashem Liton and M. Rabiul Islam

    2006-06-01

    Full Text Available Condensation of benzil (1 with urea, monophenyl urea and diphenyl urea in the presence of absolute ethanol using 30% aqueous NaOH gave the products 1a, 1b and 1c respectively and also with thiourea, monomethyl thiourea, dimethyl thiourea and diethyl thiourea the products 2a, 2b, 2c and 2d were obtained. Methylation of the product, 2a in the presence of dimethyl formamide (DMF using K2CO3 formed 2. The compounds 1b, 1c, 2b, 2c and 2 showed highly cytotoxic activity and the compounds 1a, 2a, 2d showed relatively low cytotoxic activity against brine shrimp lethality bioassay.

  12. Studies regarding the effects of an antioxidant compound in top athletes.

    Science.gov (United States)

    Drăgan, I; Dinu, V; Cristea, E; Mohora, N; Ploesteanu, E; Stroescu, V

    1991-01-01

    The authors performed a controlled trial in 15 top junior athletes (road cyclists) in order to make evident some antioxidant effects of a new compound, containing selenium, vitamin E, glutathion and cysteine, prepared as tablets. Nonproteic -SH and lipid peroxides (MDA) in blood have been recorded initially on basal conditions and 3 weeks later--during the time the athletes received daily, before training session, 2 h cycling on road about 70km--2 tablets of the antioxidant product (respectively placebo). Then, after one week we applied the cross over method. 3 weeks of antioxidant treatment induced significant increase of the nonproteic -SH and significant decrease of the lipid peroxides (MDA), especially in comparison with placebo treatment. These results support the idea of some antioxidant effects of this compound which might be useful in the biological preparation of endurance athletes.

  13. QSPR Study on Octanol/water Partition Coefficient (lgKow) of Substituted Naphthalin Compounds

    Institute of Scientific and Technical Information of China (English)

    ZENG Xiao-Lan; WANG Zun-Yao; ZHAI Zhi-Cai; ZHU Jin-Jin

    2007-01-01

    Structural parameters of 24 substituted naphthalin compounds were computed at four levels using Hartree-Fock and DFT methods. Based on the experimental data of octanol/water partition coefficient (lgKow), three-parameter (energy of the highest occupied molecular orbital (EHOMO), the most positive atomic net charges of molecule (q+) and molecular average polarizability (α)) dependent equations were developed using structural parameters as theoretical descriptors. Especially, lgKow dependent equation calculated at the HF/6-311G** level is more advantageous than others in view of their correlation and predictive abilities. This dependent equation was validated by variance inflation factors (VIF) and t-test methods and used to predict lgKow of eight designed compounds. Upon comparison, the predictive abilities of our work are all more advantageous than those calculated from molecular property calculator program.

  14. Synthesis, Mass Spectrometric Studies, and Biological Evaluation of 3,5-Dimethoxyhomophthalic Acid and Related Compounds

    Institute of Scientific and Technical Information of China (English)

    GHULAM Qadeer; NASIM Hasan-rama; FAN Zhi-jin

    2007-01-01

    3,5-Dimethoxyhomophthalic acid was synthesized in four steps from 3,5-dimethoxycinnamic acid via a series of reactions including cyclization of 3-(3' ,5'-dimethoxyphenyl) propionic acid to 5,7-dimethoxy-1-indanone and oxidative decomposition of methyl-2-hydroxy-2-[ 5,7-dimethyoxy-1-oxo-1H-inden-2 (3H) -ylidene ] acetate to 3,5-dimethoxyhomophthalic acid. The synthesized compounds were characterized by elemental analysis, IR, 1H NMR, and MS. The biological evaluation experiments of 3,5-dimthoxyhomophthalic acid and the related synthesized compounds were also carried out. Naturally occurring biologically active isocoumarins were prepared in a single step by the condensation of the homophthalic acid with appropriate acid chlorides.

  15. Study on the Mechanism of Compound Mistletoe Fluidextract in Relieving Hypertension

    Institute of Scientific and Technical Information of China (English)

    YE Fang; DU Guang-zhong; CUI Ai-qing; LU Xiao-ting; WANG You-jing

    2009-01-01

    Objective: To observe the effect of Fufang Jisheng Liujin Gao (复文寄生流浸膏 Compound Mistletoe Fluidextract) on blood pressure in the spontaneous hypertensive rats (SHR) and the renal hypertensive dogs (RHD). Methods: The blood pressure-decreasing effects of single administration and 14-day consecutive administration of Compound Mistletoe Fluidextract (CMF) in SHR and RHD were investigated and compared with that of Niuhuang Jiangya Wan (牛黄降压丸 Bezoar Hypertension-relieving Pills). Results: Both single administration and 14-day consecutive administration of CMF had significant hypotensive effects in SHR and RHD. Conclusion: The hypotensive action of CMF is gradual, but lasts for a longer period, with a dose-effect relationship in a range of doses.

  16. A Theoretical Study on Pyrolysis and Sensitivity of Energetic Compounds(Ⅴ)--Nitro Derivatives of Methylbenzene

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    UHF-SCF-AM1 MO calculations were performed for two kinds of pyrolysis reactions of seven nitro derivatives of methylbenzene(homolysis reactions by the rupture of bond C-NO2 into radicals and isomerization reactions in the way of methyl H transferring to the ortho nitro O atom). The molecular geometries of the reactants, the transition states and the products of the fourteen reactions were fully optimized. The activation energies for these two kinds of reactions have been obtained. The results indicate that this category of compounds is more easily pyrolyzed by being initiated via isomerization reactions. A parallel relationship exists between the activation energy of the isomerization reactions and the impact sensitivity of the seven titled compounds.

  17. Quasielastic neutron scattering studies of H motion in Laves-phase compounds

    CERN Document Server

    Skripov, A V; Cook, J C; Udovic, T J; Hempelmann, R

    2002-01-01

    The results of our quasielastic neutron scattering measurements for a number of cubic Laves-phase hydrides AB sub 2 H sub x are consistent with the coexistence of two types of H motion: the fast localized jumps within the hexagons formed by interstitial g (A sub 2 B sub 2) sites and the slower hopping from one hexagon to another. The analysis of these results has revealed the relation between the hydrogen-hopping rates, the g-g distances, and the ratio of the metallic radii R sub A and R sub B of the elements A and B forming the AB sub 2 compound. We conclude that the behavior of the two frequency scales of H motion is determined mainly by R sub A /R sub B. A new type of localized H motion is predicted for compounds with R sub A /R sub B >1.35. (orig.)

  18. Antimicrobial and Volatile Compounds Study of Four Spices Commonly Used in Indonesian Culinary

    OpenAIRE

    Hamad, Alwani; Mahardika, M. Gigih Panji; Istifah, Istifah; Hartanti, Dwi

    2016-01-01

    The n-hexane extracts of the aerial parts of Ocimum x citriodorum and the leaves of Cymbopogon citratus, Syzygium aromaticum and Syzygium polyanthum were evaluated for their antimicrobial activity against some food borne microorganisms. Their volatile compounds were analyzed by gas chromatography/mass spectrometry (GC/MS). All extracts inhibited the growth of Bacillus subtilis. The extract of S. polyanthum showed the strongest inhibitory activity against Salmonella typhimurium. The growth of ...

  19. Electron paramagnetic resonance study of ternary CuII compounds with glycine and phenanthroline

    Indian Academy of Sciences (India)

    Ricardo C Santana; Anderson B C Araújo; Jesiel F Carvalho; Rafael Calvo

    2014-01-01

    We report here electron paramagnetic resonance (EPR) measurements at 9 and 34 GHz, and room temperature (), in powder and single crystal samples of the ternary compounds of copper nitrate or copper chloride with glycine and 1,10-phenanthroline [Cu(Gly)(phen)(H2O)]·NO3·1.5H2O (1) and [Cu(Gly)(phen)Cl]2·7H2O (2). In compound 1, the copper ions are arranged in 1-D chains along one of the crystal axes connected by syn-anti carboxylate ligands, while in 2 the array is nearly 3-D and the connections involve -bonds and stacking interactions. The angular variation of the squared g-factor and the line width were measured as a function of orientation of the magnetic field (0) in three orthogonal crystal planes. In both compounds we observed one resonance without hyperfine structure for any magnetic field orientation which we attribute to the collapse of the hyperfine coupling and of the resonances of two chemically identical but rotated coppers in the unit cell, produced by exchange interactions. We analyse the results in terms of the structures of the compounds and chemical paths connecting neighbour copper ions which support the exchange interactions between neighbour spins in the lattice. Considering the collapse of the EPR signals of rotated sites in the lattices we are able to set lower limits to the exchange interactions, which are supported by weak equatorial-apical carboxylate bridges in 1, and by paths containing hydrogen bonds and aromatic - interactions in 2. Broadening due to dipole-dipole couplings and hyperfine interactions are strongly reduced by these exchange couplings and their role in the EPR line width is more difficult to recognize.

  20. Theoretical and experimental study on lipophilicity and wound healing activity of ginger compounds

    Institute of Scientific and Technical Information of China (English)

    Mohammed Afroz Bakht; Mohammed F Alajmi; Perwez Alam; Aftab Alam; Prawez Alam; Tariq Mohammed Aljarba

    2014-01-01

    Objective: To correlate the chromatographic and computational method to calculate lipophilicity of selected ginger compounds and to observe the effects of log P on wound healing. Methods:Mixtures of acetonitrile and water with acetonitrile content between 95% and 50% v/v in 5% increments were kept separately in 10 different chromatographic chambers, saturated with solvent for 2 h. Spots were observed under UV light at λ=254 nm p-anisaldehyde used as a spraying reagent. Theoretical calculation was done using the Alogps 2.1 online program at www. vcclab.org/lab/alogps. For percentage wound contraction, five groups of animal (mice) (25-30 g) of either sex were selected. Wound were created on dorsal surface of animals using toothed forceps, scalpel and pointed scissors. The wound areas were calculated using vernier caliper. After making wound mice were orally administered 35 mg/kg 6-shogoal, 6-gingerol, 8-gingerol and 10-gingerol respectively. Group E as the control group received tap water. Results:The lipophilicity values determined in thin layer chromatography were correlated with the theoretically calculated various log P by linear regression analysis. Significant correlations were found between log P values calculated by software program and the experimental reversed-phase thin-layer chromatography data. Order of wound healing property of ginger compounds is directly dependent on lipophilicity i.e. more lipophilic compound has highest activity. Conclusions:Experimentally determined lipophilicity (RMO) values were correlated with log Pdetermined by software's and found satisfactory. Lipophilicity (RMO) is a useful parameter for the determination and prediction of biological activity of ginger compounds.

  1. SURVEY ON CLINICAL STUDY OF COMPOUND ACUPUNCTURE ANESTHESIA IN RESENT 10 YEARS IN CHINA

    Institute of Scientific and Technical Information of China (English)

    秦必光; 胡北喜; 等

    2002-01-01

    In the present paper,the authors make a review on the progresses of acupuncture anesthesia(AA) from (1)historical development,(2)research on acupuncture combined with local anesthesia;(3)research on acupuncture combined with epidural anesthesia;and (4)research on acupuncture combined with general anesthesia.Compound acupuncture anesthesia provides a new anesthetic measure for surgical operations and has a definits analyesic effect and many advantages,and should be investigated further.

  2. Volatile Organic Compound and Particulate Emission Studies of AF (Air Force) Paint Booth Facilities. Phase 1.

    Science.gov (United States)

    1988-07-01

    Schaums outline series, McGraw Hill Book Company, September 1986. 13. Rule 451; Surface Coatings of Miscellaneous Metal Parts and Products. Sacramento...analyzed as soon as possible by the Acurex Chemistry Laboratory. The accuracy and completeness of each data set were determined based on the quality...compounds of interest. Three sets of tubes were submitted for analysis to the Acurex Chemistry Laboratory, thus three clean tubes were spiked with tne

  3. Comparative study of four QSAR models of aromatic compounds to aquatic organisms

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Quantitative structure-activity relationships (QSARs) were developed for 43 aromatic compounds toxicity to Photobacterium phosphoreum and Daphnia magna based on four methods: octanol/water partition coefficient, linear solvation energy relationship, molecular connectivity index and group contribution. Through the evaluation of four QSAR methods, LSER was proved to be the best. And it applied to the widest range of chemicals with the greatest accuracy.

  4. A case study: shelf-life of smoked herring fillets by volatile compounds analysis.

    Directory of Open Access Journals (Sweden)

    Cristian Bernardi

    2014-02-01

    Full Text Available Two different products of vacuum packed cold smoked herrings were analyzed at time intervals in order to evaluate the efficiency of the processing and product stability. Microbiological total counts, lactic acid bacteria, total coliforms, pH, water activity, water content, salt content (WPS were determined. Differences in hygienic conditions and salt content were found. Principal components analysis (PCA of volatile compounds determined by GC-MS analysis allowed the differentiation of the processing.

  5. Determination of Carbonyl Compounds in Cigarette Mainstream Smoke. The CORESTA 2010 Collaborative Study and Recommended Method

    Directory of Open Access Journals (Sweden)

    Intorp M

    2014-12-01

    Full Text Available A recommended method has been developed and published by CORESTA, applicable to the quantification of selected carbonyl compounds (acetaldehyde, formaldehyde, acetone, acrolein, methyl ethyl ketone, crotonaldehyde, propionaldehyde and butyraldehyde in cigarette mainstream smoke. The method involved smoke collection in impinger traps, derivatisation of carbonyls with 2,4-dinitrophenylhydrazine (DNPH, separation of carbonyl hydrazones by reversed phase high performance liquid chromatography and detection by ultra violet or diode array.

  6. Ab initio study of antiphase boundaries and stacking faults in L12 and DO22 compounds

    DEFF Research Database (Denmark)

    Rosengaard, N. M.; Skriver, Hans Lomholt

    1994-01-01

    We have performed ab initio calculations of the energies of antiphase boundaries as well as complex and superlattice intrinsic stacking faults in nine intermetallic compounds observed in the face-centered-cubic L1(2) and DO22 structures. The calculations were performed by means of a Green's funct......'s function technique based on the linear-muffin-tin-orbitals method within the tight-binding and atomic-sphere approximations....

  7. Studies on the Synthesis and the Structure of Ferric Aluminum Magnesium Hydrotalcite-like Compounds

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The particles of ferric aluminum magnesium hydrotalcite-like compounds (Fe-Al-Mg_HTlc) were synthesized by co-precipitation method. It was found that when n(Fe)/n(Al+Mg+Fe)0.30, Al(OH)3 will emerge; when the molar ratio of Fe/(Fe+Al+Mg) >0.30, the amorphous composition will appear. Hence Fe3+ and Al3+ have no concentration superposition effect on the crystal structure of the samples.

  8. DRIFT and DRUV spectroscopy methods for studying the interaction of metal compounds with native cellulose

    OpenAIRE

    Visekruna, Jovana

    2015-01-01

    Dissertação de mestrado, Qualidade em Análises, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015 Cellulose, the most abundant organic polymer on earth, has numerous applications including the application in pharmacy as excipient in different kinds of pharmaceutical formulations where it comes in contact with metal compounds used in therapeutic purposes. Chemically, is composed of hundreds to thousands of β 1→4 linked D glucopyranose units. It is insoluble in water and most...

  9. 3D-QSAR and docking studies of estrogen compounds based on estrogen receptor β

    Institute of Scientific and Technical Information of China (English)

    YANG XuShu; WANG XiaoDong; LUO Si; JI Li; QIN Liang; LI Rong; SUN Cheng; WANG LianSheng

    2009-01-01

    Close attention has been paid to estrogen compounds because these chemicals may pose a serious threat to the health of humans and wildlife.Estrogen receptor (ER) exists as two subtypes,ERo and ERβ.The difference in amino acids sequence of the binding sites of ERo and ERβ might lead to a result that some synthetic estrogens and naturally occurring steroidal ligands have different relative affinities and binding modes for ERa and ERβ.In this investigation,comparative molecular similarity indices analysis (CoMSIA) was performed on 50 estrogen compounds binding ERβ to find out the structural relationship with the activities.We also compared two alignment schemes employed in CoMSIA analysis,namely,atom-fit and receptor-based alignment,with respect to the predictive capability of their respective models for structurally diverse data sets.The model with the significant correlation and the best predictive power (R2=0.961,q2LOO=0.671,Rp2red=0.722) was achieved.The CoMSIA and docking results revealed the structural features related to an activity and provided an insight into molecular mechanisms of estrogenic activities for estrogen compounds.

  10. Syntheses, Characterization, Resolution, and Biological Studies of Coordination Compounds of Aspartic Acid and Glycine

    Science.gov (United States)

    Akinkunmi, Ezekiel; Ojo, Isaac; Adebajo, Clement; Isabirye, David

    2017-01-01

    Enantiomerically enriched coordination compounds of aspartic acid and racemic mixtures of coordination compounds of glycine metal-ligand ratio 1 : 3 were synthesized and characterized using infrared and UV-Vis spectrophotometric techniques and magnetic susceptibility measurements. Five of the complexes were resolved using (+)-cis-dichlorobis(ethylenediamine)cobalt(III) chloride, (+)-bis(glycinato)(1,10-phenanthroline)cobalt(III) chloride, and (+)-tris(1,10-phenanthroline)nickel(II) chloride as resolving agents. The antimicrobial and cytotoxic activities of these complexes were then determined. The results obtained indicated that aspartic acid and glycine coordinated in a bidentate fashion. The enantiomeric purity of the compounds was in the range of 22.10–32.10%, with (+)-cis-dichlorobis(ethylenediamine)cobalt(III) complex as the more efficient resolving agent. The resolved complexes exhibited better activity in some cases compared to the parent complexes for both biological activities. It was therefore inferred that although the increase in the lipophilicity of the complexes may assist in the permeability of the complexes through the cell membrane of the pathogens, the enantiomeric purity of the complexes is also of importance in their activity as antimicrobial and cytotoxic agents. PMID:28293149

  11. 3D-QSAR and docking studies of estrogen compounds based on estrogen receptor β

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Close attention has been paid to estrogen compounds because these chemicals may pose a serious threat to the health of humans and wildlife. Estrogen receptor (ER) exists as two subtypes, ERα and ERβ. The difference in amino acids sequence of the binding sites of ERα and ERβ might lead to a result that some synthetic estrogens and naturally occurring steroidal ligands have different relative affinities and binding modes for ERα and ERβ. In this investigation, comparative molecular similarity indices analysis (CoMSIA) was performed on 50 estrogen compounds binding ERβ to find out the structural relationship with the activities. We also compared two alignment schemes employed in CoMSIA analy-sis, namely, atom-fit and receptor-based alignment, with respect to the predictive capability of their respective models for structurally diverse data sets. The model with the significant correlation and the best predictive power (R2=0.961, qL 2OO=0.671, RP 2red=0.722) was achieved. The CoMSIA and docking results revealed the structural features related to an activity and provided an insight into molecular mechanisms of estrogenic activities for estrogen compounds.

  12. Syntheses, Characterization, Resolution, and Biological Studies of Coordination Compounds of Aspartic Acid and Glycine.

    Science.gov (United States)

    Aiyelabola, Temitayo; Akinkunmi, Ezekiel; Ojo, Isaac; Obuotor, Efere; Adebajo, Clement; Isabirye, David

    2017-01-01

    Enantiomerically enriched coordination compounds of aspartic acid and racemic mixtures of coordination compounds of glycine metal-ligand ratio 1 : 3 were synthesized and characterized using infrared and UV-Vis spectrophotometric techniques and magnetic susceptibility measurements. Five of the complexes were resolved using (+)-cis-dichlorobis(ethylenediamine)cobalt(III) chloride, (+)-bis(glycinato)(1,10-phenanthroline)cobalt(III) chloride, and (+)-tris(1,10-phenanthroline)nickel(II) chloride as resolving agents. The antimicrobial and cytotoxic activities of these complexes were then determined. The results obtained indicated that aspartic acid and glycine coordinated in a bidentate fashion. The enantiomeric purity of the compounds was in the range of 22.10-32.10%, with (+)-cis-dichlorobis(ethylenediamine)cobalt(III) complex as the more efficient resolving agent. The resolved complexes exhibited better activity in some cases compared to the parent complexes for both biological activities. It was therefore inferred that although the increase in the lipophilicity of the complexes may assist in the permeability of the complexes through the cell membrane of the pathogens, the enantiomeric purity of the complexes is also of importance in their activity as antimicrobial and cytotoxic agents.

  13. Study of Raman spectroscopic analysis method for sodium compounds at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Fumiyoshi; Ohtori, Norikazu [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center

    2002-09-01

    High-temperature sodium on exposure to air produces a corrosive melt including Na{sub 2}O, Na{sub 2}O{sub 2} and NaOH after reaction with oxygen and moisture. If the melt contacts steel, several sodium-iron complex oxides will be produced by the corrosion reaction. To contribute to elucidation of the corrosion mechanism, the Raman spectroscopic technique for analysis of strongly corrosive sodium compounds was developed and the behavior of corrosive chemical species in the compounds was investigated. Several Raman spectra of a series of typical sodium compounds such as Na{sub 2}O{sub 2} were measured in the range from room temperature to 1,073K. Subsequently, a simulated corrosive mixture of molten sodium hydroxide with peroxide was investigated, and peroxide ion was detected up to 823K. Thus, peroxide ion can be a corrosive chemical species in the melt at high temperature. Moreover, Raman spectra obtained for several sodium-iron complex oxides, e.g. Na{sub 4}FeO{sub 3}, indicate that each oxide can be identified up to 573K. (author)

  14. Synthesis and Antiplatelet Activity of Antithrombotic Thiourea Compounds: Biological and Structure-Activity Relationship Studies

    Directory of Open Access Journals (Sweden)

    André Luiz Lourenço

    2015-04-01

    Full Text Available The incidence of hematological disorders has increased steadily in Western countries despite the advances in drug development. The high expression of the multi-resistance protein 4 in patients with transitory aspirin resistance, points to the importance of finding new molecules, including those that are not affected by these proteins. In this work, we describe the synthesis and biological evaluation of a series of N,N'-disubstituted thioureas derivatives using in vitro and in silico approaches. New designed compounds inhibit the arachidonic acid pathway in human platelets. The most active thioureas (compounds 3d, 3i, 3m and 3p displayed IC50 values ranging from 29 to 84 µM with direct influence over in vitro PGE2 and TXA2 formation. In silico evaluation of these compounds suggests that direct blockage of the tyrosyl-radical at the COX-1 active site is achieved by strong hydrophobic contacts as well as electrostatic interactions. A low toxicity profile of this series was observed through hemolytic, genotoxic and mutagenic assays. The most active thioureas were able to reduce both PGE2 and TXB2 production in human platelets, suggesting a direct inhibition of COX-1. These results reinforce their promising profile as lead antiplatelet agents for further in vivo experimental investigations.

  15. Development of a direct exposure system for studying the mechanisms of central neurotoxicity caused by volatile organic compounds

    OpenAIRE

    2015-01-01

    Many volatile organic compounds (VOCs) used in work places are neurotoxic. However, it has been difficult to study the cellular mechanisms induced by a direct exposure to neurons because of their high volatility. The objective of this study was to establish a stable system for exposing brain slices to VOCs. With a conventional recording system for brain slices, it is not possible to keep a constant bath concentration of relatively highly volatile solvents, e.g. 1-bromopropane (1-BP). Here we ...

  16. Studies of obtaining and stability in aqueous medium of new complex compounds of Ti(IV) and Zr(IV) used in ecological leather tanning

    Science.gov (United States)

    Crudu, Marian; Sibiescu, Doina; Rosca, Ioan; Sutiman, Daniel; Vizitiu, Mihaela

    2009-01-01

    In this paper, the study of obtaining new coordination compounds of Ti(IV) and Zr(IV) using as ligand: D,L-β-iso-butyric acid, is presented. Also, the stability of these compounds in aqueous medium is studied. The studies of obtaining and of stability of the new compounds were accomplished in aqueous solutions using methods characteristic for coordination compounds: conductance and pH measurements. The combination ratios and the stability were determined with methods characteristic for studies in solutions. From experimental data resulted that the combination ratio of central metallic atoms with the ligand derived from D,L-β-iso-butyric acid was 1:2. From experimental data resulted that in strong acid and strong basic mediums, the coordination compounds could not be obtained. The optimal stability of the studied compounds is limited between 3-6, pH - values. This fact is in accordance with the conditions of using these compounds in ecological leather tanning. Of great importance is that these compounds were used with very good results in tanning processes of different types of leather. This fact evidenced that the ecological alternative of tanning is better than non-ecological tanning using chrome compounds. The importance of this paper consists in obtaining new coordination compounds that can be used in ecological leather tanning.

  17. Solid-state NMR/NQR and first-principles study of two niobium halide cluster compounds.

    Science.gov (United States)

    Perić, Berislav; Gautier, Régis; Pickard, Chris J; Bosiočić, Marko; Grbić, Mihael S; Požek, Miroslav

    2014-01-01

    Two hexanuclear niobium halide cluster compounds with a [Nb6X12](2+) (X=Cl, Br) diamagnetic cluster core, have been studied by a combination of experimental solid-state NMR/NQR techniques and PAW/GIPAW calculations. For niobium sites the NMR parameters were determined by using variable Bo field static broadband NMR measurements and additional NQR measurements. It was found that they possess large positive chemical shifts, contrary to majority of niobium compounds studied so far by solid-state NMR, but in accordance with chemical shifts of (95)Mo nuclei in structurally related compounds containing [Mo6Br8](4+) cluster cores. Experimentally determined δiso((93)Nb) values are in the range from 2,400 to 3,000 ppm. A detailed analysis of geometrical relations between computed electric field gradient (EFG) and chemical shift (CS) tensors with respect to structural features of cluster units was carried out. These tensors on niobium sites are almost axially symmetric with parallel orientation of the largest EFG and the smallest CS principal axes (Vzz and δ33) coinciding with the molecular four-fold axis of the [Nb6X12](2+) unit. Bridging halogen sites are characterized by large asymmetry of EFG and CS tensors, the largest EFG principal axis (Vzz) is perpendicular to the X-Nb bonds, while intermediate EFG principal axis (Vyy) and the largest CS principal axis (δ11) are oriented in the radial direction with respect to the center of the cluster unit. For more symmetrical bromide compound the PAW predictions for EFG parameters are in better correspondence with the NMR/NQR measurements than in the less symmetrical chlorine compound. Theoretically predicted NMR parameters of bridging halogen sites were checked by (79/81)Br NQR and (35)Cl solid-state NMR measurements.

  18. NATO Advanced Study Institute on Mixed-Valence Compounds : Theory and Applications in Chemistry, Physics, Geology, and Biology

    CERN Document Server

    1980-01-01

    It has been a decade since two seminal reviews demonstrated that mixed-valence compounds share many unique and fascinating features. The insight pro­ vided by those early works has promoted a great deal of both experimental and theoretical study. As a result of extensive efforts, our understanding of the bonding and properties of mixed-valence compounds has advanced substantially. There has been no compre­ hensive treatment of mixed-valence compounds since 1967, and the meeting convened at Oxford in September, 1979, provided a unique opportunity to examine the subject and its many ramifications. Mixed-valence compounds play an important role in many fields. Although the major impact of the subject has been in chemistry, its importance has become increasingly clear in solid state physics, geology, and biology. Extensive interest and effort in the field of molecular metals has demonstrated that mixed-valency is a prerequisite for high elec­ trical conductivity. The intense colors of many minerals have been s...

  19. Study on a method for loading a Li compound to produce tritium using high-temperature gas-cooled reactor

    Energy Technology Data Exchange (ETDEWEB)

    Nakaya, Hiroyuki, E-mail: nakaya@nucl.kyushu-u.ac.jp [Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, 744 Motooka, Fukuoka 8190395 (Japan); Matsuura, Hideaki [Department of Applied Quantum Physics and Nuclear Engineering, Kyushu University, 744 Motooka, Fukuoka 8190395 (Japan); Katayama, Kazunari [Department of Advanced Energy Engineering Science, Kyushu University, 6-1 Kasuga-koen, Kasuga 8168580 (Japan); Goto, Minoru; Nakagawa, Shigeaki [Japan Atomic Energy Agency, 4002 Oarai, Ibaraki (Japan)

    2015-10-15

    Highlights: • Tritium production by a high-temperature gas-cooled reactor was studied. • The loading method considering tritium outflow suppression was estimated. • A reactor with 600 MWt produced 400–600 g of tritium for 180 days. • A possibility that tritium outflow can be sufficiently suppressed was shown. - Abstract: Tritium production using high-temperature gas-cooled reactors and its outflow from the region loading Li compound into the helium coolant are estimated when considering the suppression of tritium outflow. A Li rod containing a cylindrical Li compound placed in an Al{sub 2}O{sub 3} cladding tube is assumed as a method for loading Li compound. A gas turbine high-temperature reactor of 300 MW electrical nominal capacity (GTHTR300) with 600 MW thermal output power is considered and modeled using the continuous-energy Monte Carlo transport code MVP-BURN, where burn-up simulations are carried out. Tritium outflow is estimated from equilibrium solution for the tritium diffusion equation in the cladding tube. A GTHTR300 can produce 400–600 g of tritium over a 180-day operation using the chosen method of loading the Li compound while minimizing tritium outflow from the cladding tube. Optimizing tritium production while suppressing tritium outflow is discussed.

  20. 姜汁柠檬复合饮料的研制%Study on Compound Beverage with Ginger and Lemon

    Institute of Scientific and Technical Information of China (English)

    李欣芮; 刘畅

    2016-01-01

    以生姜、柠檬为主要研究对象,对姜汁柠檬复合饮料加工工艺进行研究。在单因素实验的基础上通过正交试验,确定姜汁柠檬复合饮料的最佳配方。结果表明:最佳调配方案为姜汁添加量7%、柠檬汁加量为12%、蜂蜜添加量为6%、白砂糖添加量为10%。稳定剂的最佳调配方案为阿拉伯胶0.1%、黄原胶为0.1%。%The study focused on the processing technology of compound juice made from ginger and lemon. The formula for the compound beverage was confirmed by single factor experiment and orthogonal test.The result showed the optimum formula of the compound healthy beverage is obtained,which is 7% ginger extract,12% lemon juice extract,6% honey and 10% white granulated sugar in the compound healthy beverage.The optimum formula of the additive is obtained,which is 0.1% acacia and 0.1%xanthan gum .

  1. Occurrence of Endocrine Active Compounds and Biological Responses in the Mississippi River - Study Design and Data, June through August 2006

    Science.gov (United States)

    Lee, Kathy E.; Yaeger, Christine S.; Jahns, Nathan D.; Schoenfuss, Heiko L.

    2008-01-01

    Concern that selected chemicals in the environment may act as endocrine active compounds in aquatic ecosystems is widespread; however, few studies have examined the occurrence of endocrine active compounds and identified biological markers of endocrine disruption such as intersex occurrence in fish longitudinally in a river system. This report presents environmental data collected and analyzed by the U.S. Geological Survey, Minnesota Pollution Control Agency and St. Cloud State University as part of an integrated biological and chemical study of endocrine disruption in fish in the Mississippi River. Data were collected from water, bed sediment, and fish at 43 sites along the river from the headwaters at Lake Itasca to 14 miles downstream from Brownsville, Minnesota during June through August 2006. Twenty-four individual compounds were detected in water samples, with cholesterol, atrazine, N,N-diethyl-meta-toluamide, metolachlor, and hexahydrohexamethylcyclopentabenzopyran detected most frequently (in at least 10 percent of the samples). The number of compounds detected in water per site ranged from 0 to 8. Forty individual compounds were detected in bed-sediment samples. The most commonly detected compounds (in at least 50 percent of the samples) were indole, beta-sitosterol, cholesterol, beta-stigmastanol, 3-methyl-1H-indole, p-cresol, pyrene, phenol, fluoranthene, 3-beta coprostanol, benzo[a]pyrene, acetophenone, and 2,6-dimethylnaphthalene. The total number of detections in bed sediment (at a site) ranged from 3 to 31. The compounds NP1EO, NP2EO, and 4-nonylphenol were detected in greater than 10 percent of the samples. Most (80 percent) female fish collected had measurable concentrations of vitellogenin. Vitellogenin also was detected in 62, 63, and 33 percent of male carp, smallmouth bass, and redhorse, respectively. The one male walleye sample plasma sample analyzed had a vitellogenin detection. Vitellogenin concentrations were lower in male fish (not

  2. Beer thiol-containing compounds and redox stability: kinetic study of 1-hydroxyethyl radical scavenging ability.

    Science.gov (United States)

    de Almeida, Natália E C; Lund, Marianne N; Andersen, Mogens L; Cardoso, Daniel R

    2013-10-02

    The 1-hydroxyethyl radical is a central intermediate in oxidative reactions occurring in beer. The reactivity of thiol-containing compounds toward 1-hydroxyethyl radical was evaluated in beer model solutions using a competitive kinetic approach, employing the spin-trap 4-POBN as a probe and by using electron paramagnetic resonance to detect the generated 1-hydroxyethyl/4-POBN spin adduct. Thiol-containing compounds were highly reactive toward the 1-hydroxyethyl radical with apparent second-order rate constants close to the diffusion limit in water and ranging from 0.5 × 10⁹ L mol⁻¹ s⁻¹ for the His-Cys-Lys-Phe-Trp-Trp peptide to 6.1 × 10⁹ L mol⁻¹ s⁻¹ for the reduced lipid transfer protein 1 (LTP1) isolated from beer. The reactions gave rise to a moderate kinetic isotope effect (k(H)/k(D) = 2.3) suggesting that reduction of the 1-hydroxyethyl radical by thiol-containing compounds takes place by hydrogen atom abstraction from the RSH group rather than electron transfer. The content of reduced thiols in different beers was determined using a previously established method based on ThioGlo-1 as the thiol derivatization reagent and detection of the derivatized thiols by reverse-phase liquid chromatography coupled to a fluorescence detector. The total level of thiol in beer (oxidized and reduced) was determined after a reduction step employing 3,3',3″-phosphanetriyltripropanoic acid (TCEP) as the disulfide reductant. A good correlation among total protein and total thiol content in different beers was observed. The results suggest a similar ratio between reduced thiols and disulfides in all of the tested beers, which indicates a similar redox state.

  3. Comparative study of the endocrine-disrupting activity of bisphenol A and 19 related compounds.

    Science.gov (United States)

    Kitamura, Shigeyuki; Suzuki, Tomoharu; Sanoh, Seigo; Kohta, Ryuki; Jinno, Norimasa; Sugihara, Kazumi; Yoshihara, Shin'ichi; Fujimoto, Nariaki; Watanabe, Hiromitsu; Ohta, Shigeru

    2005-04-01

    The endocrine-disrupting activities of bisphenol A (BPA) and 19 related compounds were comparatively examined by means of different in vitro and in vivo reporter assays. BPA and some related compounds exhibited estrogenic activity in human breast cancer cell line MCF-7, but there were remarkable differences in activity. Tetrachlorobisphenol A (TCBPA) showed the highest activity, followed by bisphenol B, BPA, and tetramethylbisphenol A (TMBPA); 2,2-bis(4-hydroxyphenyl)-1-propanol, 1,1-bis(4-hydroxyphenyl)propionic acid and 2,2-diphenylpropane showed little or no activity. Anti-estrogenic activity against 17beta-estradiol was observed with TMBPA and tetrabromobisphenol A (TBBPA). TCBPA, TBBPA, and BPA gave positive responses in the in vivo uterotrophic assay using ovariectomized mice. In contrast, BPA and some related compounds showed significant inhibitory effects on the androgenic activity of 5alpha-dihydrotestosterone in mouse fibroblast cell line NIH3T3. TMBPA showed the highest antagonistic activity, followed by bisphenol AF, bisphenol AD, bisphenol B, and BPA. However, TBBPA, TCBPA, and 2,2-diphenylpropane were inactive. TBBPA, TCBPA, TMBPA, and 3,3'-dimethylbisphenol A exhibited significant thyroid hormonal activity towards rat pituitary cell line GH3, which releases growth hormone in a thyroid hormone-dependent manner. However, BPA and other derivatives did not show such activity. The results suggest that the 4-hydroxyl group of the A-phenyl ring and the B-phenyl ring of BPA derivatives are required for these hormonal activities, and substituents at the 3,5-positions of the phenyl rings and the bridging alkyl moiety markedly influence the activities.

  4. Single crystal growth, superconductivity and Fermi surface study of plutonium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Haga, Y. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan)], E-mail: haga.yoshinori@jaea.go.jp; Aoki, D. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Yamagami, H. [Department of Physics, Faculty of Science, Kyoto Sangyo University, Kyoto 603-8555 (Japan); Matsuda, T.D. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Nakajima, K.; Arai, Y. [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Yamamoto, E.; Nakamura, A. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Homma, Y. [Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Shiokawa, Y. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Institute for Materials Research, Tohoku University, Oarai, Ibaraki 311-1313 (Japan); Onuki, Y. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan)

    2007-10-11

    Single crystals of plutonium compounds PuRhGa{sub 5} and PuIn{sub 3} are successfully grown. For PuRhGa{sub 5}, anisotropy of the superconducting upper critical field was found and analyzed by the anisotropic mass model, consistent with quasi-two-dimensional electronic states predicted by band calculations. On the other hand, the de Haas-van Alphen oscillation was observed in PuIn{sub 3}. By comparing with the band calculations, it is concluded that 5f electrons are itinerant in PuIn{sub 3}.

  5. Syntheses, magnetic and spectral studies on polystyrene supported coordination compounds of bidentate and tetradentate Schiff bases

    Indian Academy of Sciences (India)

    D Kumar; P K Gupta; A Syamal

    2005-05-01

    The reaction of aminomethylated polystyrene (PSCH2-NH2) and 2-hydroxyacetanilide in DMF results in the formation of polystyrene-anchored monobasic bidentate Schiff base, PSCH2-LH (I). On the other hand, the reaction of chloromethylated polystyrene (PSCH2-Cl), 3-formylsalicylic acid, ethylenediamine and acetylacetone in DMF in presence of ethyl acetate (EA) and triethylamine (TEA) produces another polystyrene-anchored dibasic tetradentate Schiff base, PSCH2-L'H2 (II). Both I and II react with a number of di-, tri- and hexavalent metal ions like Co, Ni, Cu, Zn and Cd to form polystyreneanchored coordination compounds, and these have been characterized and discussed.

  6. [Practicability study on a group of vigilant chemical compounds including chlorheridine diacetate].

    Science.gov (United States)

    Fu, Xiao-Min; Jin, Ai-Hua; Zou, Jian; Li, Qian-Li

    2002-01-01

    To test in vitro the spermatozocidine drug which can also prevent sex transmitting diseases (STD) pathogens. Chlorheridine diacetate and other three chemical compounds were applied in vitro spermatozocidine and sperm inhibitting tests. The lowest concentrations of chlorheridine diacetate and p-nitrophenol which can inhibit human sperm in 20 seconds were 1.25 mg/ml. The minimal inhibitory concentration and minimal bactericidal concentration of chlorheridine diacetate and p-nitrophenol on Streptococcus albus Stemberg were 0.125 to 0.50 mg/ml and 0.25 to 1.00 mg/ml. Chlorheridine diacetate and p-uitrophenol have strong spermatozocidine and antibacteria effects.

  7. The Study of Biogenetic Organic Compound Emissions and Ozone in a Subtropical Bamboo Forest

    Science.gov (United States)

    Bai, Jianhui; Guenther, Alex; Turnipseed, Andrew; Duhl, Tiffany; Duhl, Nanhao; van der A, Ronald; Yu, Shuquan; Wang, Bin

    2016-08-01

    Emissions of Biogenic Volatile Organic compounds (BVOCs), Photosynthetically Active Radiation (PAR), and meteorological parameters were measured in some ecosystems in China. A Relaxed Eddy Accumulation system and an enclosure technique were used to measure BVOC emissions. Obvious diurnal and seasonal variations of BVOC emissions were found. Empirical models of BVOC emissions were developed, the estimated BVOC emissions were in agreement with observations. BVOC emissions in growing seasons in the Inner Mongolia grassland, Chnagbai Mountain temperate forest, LinAn subtropical bamboo forest were estimated. The emission factors of these ecosystems were calculated.

  8. Studies on green and efficient catalytic oxidation of a triazole compound

    Science.gov (United States)

    Luo, J.; Liu, Y. C.; Huang, K. H.; Chai, T.; Wang, J. H.; Yu, Y. W.; Yuan, J. M.; Chang, S. J.; Guo, J. H.; Zhang, J.

    2016-07-01

    1-Methyl-3,5-dinitro-1,2,4-triazole is an insensitive energetic compound that can be prepared by oxidizing the nitrate salt of 1-methylguanazole. The influence of the reaction time, reaction temperature, reactant ratio, feeding method and catalytic oxidation method on the yield were discussed. The results show that the optimum reaction conditions are as follows: mass ratio of sodium tungstate to nitrate salt to 1-methylguanazole, 4:4.4; time, 5.5h; and temperature, 65-75°C. The yield of this oxidation reaction reached 51.36%.

  9. Synthesis, Structural, and Antimicrobial Studies of Some New Coordination Compounds of Palladium(II with Azomethines Derived from Amino Acids

    Directory of Open Access Journals (Sweden)

    Monika Gupta

    2013-01-01

    Full Text Available Some new coordination compounds of palladium(II have been synthesized by the reaction of palladium(II acetate with azomethines in a 1 : 2 molar ratio using acetonitrile as a reaction medium. Azomethines used in these studies have been prepared by the condensation of 2-acetyl fluorene and 4-acetyl biphenyl with glycine, alanine, valine, and leucine in methanol. An attempt has been made to probe their bonding and structures on the basis of elemental analyses and IR, 1H, and 13C NMR spectral studies. Pd(II compounds have been found to be more active than their uncomplexed ligands as both of them were screened for antibacterial, antifungal, and insecticidal activities.

  10. Cage Compounds as Potential Energetic Oxidizers: A Theoretical Study of a Cage Isomer of N2O3

    Science.gov (United States)

    2014-07-01

    in Aqueous Alkaline-Solutions – Evidence for the Existence of Molecular Isomers of Dintrogen Tetraoxide and Dintrogen Trioxide, J. [a] R.J... Molecular Volumes, J. Phys. Chem. A 2007, 111, 10874 [21] G. Singh, S. P. Felix, P. Soni, Studies on energetic compounds Part 21. Thermolysis and...25] a) P. Piecuch, M. Wloch, Renormalized coupled- cluster methods exploiting left eigenstates of the similarity-transformed Hamiltonian , J. Chem

  11. Thermal Studies of Ammonium Cyanide Reactions: A Model for Thermal Alteration of Prebiotic Compounds in Meteorite Parent Bodies

    Science.gov (United States)

    Hammer, P. G.; Locke, D. R.; Burton, A. S.; Callahan, M. P.

    2017-01-01

    Organic compounds in carbonaceous chondrites were likely transformed by a variety of parent body processes including thermal and aqueous processing. Here, we analyzed ammonium cyanide reactions that were heated at different temperatures and times by multiple analytical techniques. The goal of this study is to better understand the effect of hydrothermal alteration on cyanide chemistry, which is believed to be responsible for the abiotic synthesis of purine nucleobases and their structural analogs detected in carbonaceous chondrites.

  12. Structural, electronic, optical and thermodynamic properties of cubic REGa{sub 3} (RE = Sc or Lu) compounds: Ab initio study

    Energy Technology Data Exchange (ETDEWEB)

    Murtaza, G., E-mail: murtaza@icp.edu.pk [Materials Modeling Laboratory, Department of Physics, Islamia College Peshawar (Pakistan); Gupta, S.K. [Department of Physics, Michigan Technological University, Houghton, MI 49931 (United States); Seddik, T. [Laboratoire de Physique Quantique et de Modélisation Mathématique, Université de Mascara, 29000 Mascara (Algeria); Khenata, R., E-mail: khenata_rabah@yahoo.fr [Laboratoire de Physique Quantique et de Modélisation Mathématique, Université de Mascara, 29000 Mascara (Algeria); Alahmed, Z.A. [Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451 (Saudi Arabia); Ahmed, R. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Khachai, H. [Physics Department, Djillali Liabes University of Sidi Bel-Abbes (Algeria); Jha, P.K. [Department of Physics, Maharaja Krishnakumarsinhji Bhavnagar University, Bhavnagar 364001 (India); Bin Omran, S. [Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451 (Saudi Arabia)

    2014-06-01

    Highlights: • REGa{sub 3} (RE = Sc or Lu) compounds are mechanical stabile. • Both ScGa{sub 3} and LuGa{sub 3} exhibit metallic behavior just like other REGa{sub 3} compounds. • Melting temperature T{sub m} (K) for ScGa{sub 3} and LuGa{sub 3} are 1244.2 and 1143.8. • High absorption observed in the visible energy region. • The present study would be helpful for future experimental/theoretical explorations. - Abstract: Structural, elastic, optoelectronic and thermodynamic properties of REGa{sub 3} (RE = Sc and Lu) compounds have been studied self consistently by employing state of the art full potential (FP) linearized (L) approach of augmented plane wave (APW) plus local orbitals method. Calculations were executed at the level of Perdew–Burke and Ernzerhof (PBE) parameterized generalized gradient approximation (GGA) for exchange correlation functional in addition to modified Becke–Johnson (mBJ) potential. Our obtained results of lattice parameters show reasonable agreement to the previously reported experimental and other theoretical studies. Analysis of the calculated band structure of ScGa{sub 3} and LuGa{sub 3} compounds demonstrates their metallic character. Moreover, a positive value of calculated Cauchy pressure, in addition to reflecting their ductile nature, endorses their metallic character as well. To understand optical behavior calculations related to the important optical parameters; real and imaginary parts of the dielectric function, reflectivity R(ω), refractive index n(ω) and electron energy-loss function L(ω) have also been performed. In the present work, thermodynamically properties are also investigated by employing lattice vibrations integrated in quasi harmonic Debye model. Obtained results of volume, heat capacity and Debye temperature as a function of temperature for both compounds, at different values of pressure, are found to be consistent. The calculated value of melting temperature for both compounds (ScGa{sub 3} and Lu

  13. Ion channeling study of defects in compound crystals using Monte Carlo simulations

    Energy Technology Data Exchange (ETDEWEB)

    Turos, A., E-mail: turos@fuw.edu.pl [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland); National Centre for Nuclear Research, Andrzeja Soltana 7, 05-400 Otwock (Poland); Jozwik, P. [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland); National Centre for Nuclear Research, Andrzeja Soltana 7, 05-400 Otwock (Poland); Nowicki, L. [National Centre for Nuclear Research, Andrzeja Soltana 7, 05-400 Otwock (Poland); Sathish, N. [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland)

    2014-08-01

    Ion channeling is a well-established technique for determination of structural properties of crystalline materials. Defect depth profiles have been usually determined basing on the two-beam model developed by Bøgh (1968) [1]. As long as the main research interest was focused on single element crystals it was considered as sufficiently accurate. New challenge emerged with growing technological importance of compound single crystals and epitaxial heterostructures. Overlap of partial spectra due to different sublattices and formation of complicated defect structures makes the two beam method hardly applicable. The solution is provided by Monte Carlo computer simulations. Our paper reviews principal aspects of this approach and the recent developments in the McChasy simulation code. The latter made it possible to distinguish between randomly displaced atoms (RDA) and extended defects (dislocations, loops, etc.). Hence, complex defect structures can be characterized by the relative content of these two components. The next refinement of the code consists of detailed parameterization of dislocations and dislocation loops. Defect profiles for variety of compound crystals (GaN, ZnO, SrTiO{sub 3}) have been measured and evaluated using the McChasy code. Damage accumulation curves for RDA and extended defects revealed non monotonous defect buildup with some characteristic steps. Transition to each stage is governed by the different driving force. As shown by the complementary high resolution XRD measurements lattice strain plays here the crucial role and can be correlated with the concentration of extended defects.

  14. Ion channeling study of defects in compound crystals using Monte Carlo simulations

    Science.gov (United States)

    Turos, A.; Jozwik, P.; Nowicki, L.; Sathish, N.

    2014-08-01

    Ion channeling is a well-established technique for determination of structural properties of crystalline materials. Defect depth profiles have been usually determined basing on the two-beam model developed by Bøgh (1968) [1]. As long as the main research interest was focused on single element crystals it was considered as sufficiently accurate. New challenge emerged with growing technological importance of compound single crystals and epitaxial heterostructures. Overlap of partial spectra due to different sublattices and formation of complicated defect structures makes the two beam method hardly applicable. The solution is provided by Monte Carlo computer simulations. Our paper reviews principal aspects of this approach and the recent developments in the McChasy simulation code. The latter made it possible to distinguish between randomly displaced atoms (RDA) and extended defects (dislocations, loops, etc.). Hence, complex defect structures can be characterized by the relative content of these two components. The next refinement of the code consists of detailed parameterization of dislocations and dislocation loops. Defect profiles for variety of compound crystals (GaN, ZnO, SrTiO3) have been measured and evaluated using the McChasy code. Damage accumulation curves for RDA and extended defects revealed non monotonous defect buildup with some characteristic steps. Transition to each stage is governed by the different driving force. As shown by the complementary high resolution XRD measurements lattice strain plays here the crucial role and can be correlated with the concentration of extended defects.

  15. Feasibility study of heavy ion beams and compound target materials for muon production

    CERN Document Server

    Son, Jaebum; Kim, Gi Dong; Kim, Yong Kyun

    2015-01-01

    We have investigated the feasibility of using compound materials as target for muon production by virtue of simulations using a GEANT4 toolkit. A graphite and two thermostable compound materials, beryllium oxide (BeO) and boron carbide (B4C) were considered as muon production targets and their muon production rates for 600-MeV proton beam were calculated and compared. For thermal analysis, total heat deposited on the targets by the proton beams and the secondary particles was calculated with a MCNPX code, and then the temperature distribution of target was derived from the calculated heat by using an ANSYS code with consideration for heat transfer mechanisms, such as thermal conduction and thermal radiation. In addition, we have investigated whether the heavy ion beams can be utilized for muon production. For various beam species such as 3He2, 4He, 7Li, 10B and 12C, their muon production rates were calculated and compared with that obtained for a proton beam.

  16. Study of the cardiotoxic potential of pharmaceutical compounds in chick myocardial myocyte reaggregate cultures.

    Science.gov (United States)

    Seaman, C W; Toseland, C D; Maile, P A; Francis, I; White, D J

    1994-08-01

    Cardiotoxicity produced by doxorubicin in vivo is considered to be due to a direct effect on the myocardium and this is also a major component with toxicity of isoprenaline and digoxin. In the case of the cardiotoxicity produced at high doses by the antihypertensives hydralazine and pinacidil, an indirect mechanism operating by way of their exaggerated pharmacological effects is believed to be responsible. These compounds were examined for their cardiotoxic potential in vitro using chick myocardial myocyte reaggregate (MMR) cultures; allylamine HCl was used as a positive control. Cultures were incubated for up to 24 hr with each compound; parameters analysed were: spontaneous beating activity (SBA), lactate dehydrogenase (LDH) leakage and microscopic evidence of cytotoxicity. Allylamine, doxorubicin, digoxin and to a lesser extent isoprenaline were highly toxic to MMR cultures, as demonstrated by their effects on SBA, LDH leakage and morphology. Hydralazine showed very mild cytotoxicity at the highest concentrations with no LDH leakage; pinacidil was not cytotoxic but showed a dose-related inhibition of SBA. These results confirm the direct toxic action of doxorubicin and digoxin on myocardial cells and indicate that this is also an important mechanism in vivo for isoprenaline. The lack of any significant toxicity with hydralazine and pinacidil accords with an indirect mechanism based on their pharmacology.

  17. Structural stability and masnetism of metastable Ni-Pt intermetallic compounds studied by ab initio calculation

    Institute of Scientific and Technical Information of China (English)

    CHE XingLai; LI diaHao; DAI Ye; LIU BaiXin

    2009-01-01

    The self-consistent electronic structure calculations were carried out with the accurate frozen-core full-potential projector augmented-wave method on 13 Ni-Pt intermetallic compounds of simple crys-talline structures, i.e. A15, D019, D03 and L12 Ni3Pt and NiPt3, and α-NiAs, B1, B2, L28, and L10 NiPt. The calculations reveal that the L12 Ni3Pt, L10 NiPt and L12 NiPt3 are energetically more stable than their respective competitive structures, indicating that the three structures may be formed in some appro-priate conditions. The obtained results match well with the experimental observation or other theory predictions. It is found that there is hybridization between Ni 3d and Pt 5d states, which may signifi-cantly affect the structural stability and magnetism of metastable Ni-Pt intermetallic compounds.

  18. Antioxidant and cytotoxic activities of naturally occurring phenolic and related compounds: a comparative study.

    Science.gov (United States)

    Rao, Yerra Koteswara; Geethangili, Madamanchi; Fang, Shih-Hua; Tzeng, Yew-Min

    2007-09-01

    The antioxidant (DPPH radical and superoxide anion scavenging activities), and cytotoxic (in tumor, Jurkat, PC-3, Colon 205, HepG2, and normal PBMCs cells) activities of 16 plant phenolic or related compounds were evaluated in vitro. Different categories compounds corresponding to 10 flavonoids, three lignans, two phenolic acids, and a catechin showed significant mean differences in antioxidant and cytotoxic activities. Particularly, the flavonols, quercetin (3) and tiliroside (11) possess significant antioxidant activity, as well as cytotoxic activity against Jurkat; and Jurkat and HepG2 cells, respectively. In contrast, the flavanone, 5,7-dimethoxy-3',4'-methylenedioxyflavanone (7), and homoisoflavonoid, isobonducellin (10) shown to have no significant antioxidant activity, but exhibited potent cytotoxic activity in Jurkat and HepG2 cells, while moderate growth inhibition against Colon205 cells. Interestingly, none of these derivatives shown to have toxicity toward normal peripheral blood mononuclear cells, over the concentration range tested (5-200 microM). Cytotoxic activities of some natural flavonoids identified in the medicinal plants were evaluated for the first time.

  19. Organic compounds containing methoxy and cyanoacrylic acid: Synthesis, characterization, crystal structures, and theoretical studies

    Energy Technology Data Exchange (ETDEWEB)

    Khalaji, A. D., E-mail: alidkhalaji@yahoo.com [Golestan University, Department of Chemistry, Faculty of Science (Iran, Islamic Republic of); Maddahi, E. [Iran University of Science & Technology, Ms.C Educated, Department of Chemistry (Iran, Islamic Republic of); Dusek, M.; Fejfarova, K. [Institute of Physics of the ASCR, v.v.i. (Czech Republic); Chow, T. J. [Academia Sinica, Institute of Chemistry (China)

    2015-12-15

    Metal-free organic compounds 24-SC ((E)-2-cyano-3-(2,4-dimethoxyphenyl)acrylic acid) and 34-SC ((E)-2-cyano-3-(3,4-dimethoxyphenyl)acrylic acid), containing methoxy groups as a donor and the acrylic acid as an acceptor were synthesized and characterized by CHN, FT-IR, UV-Vis, {sup 1}H-NMR and single crystal X-ray diffraction and used as photosensitizers for the application of dye-sensitized solar cells (DSSC). The sensitizing characteristics of them were evaluated. Both compounds contain the natural molecule, its anionic form and the piperidinium cation and they differ by number of these molecules in the asymmetric unit. To get further insight into the effect of molecular structure on the performance of DSSC, their geometry and energies of HOMO and LUMO were optimized by density functional theory calculation at the B3LYP/6-31G(d) level with Gaussian 03. Overall conversion efficiencies of 0.78 under full sunlight irradiation are obtained for DSSCs based on the new metal-free organic dyes 24-SC and 34-SC.

  20. Amino acid anions in organic ionic compounds. An ab initio study of selected ion pairs.

    Science.gov (United States)

    Benedetto, A; Bodo, E; Gontrani, L; Ballone, P; Caminiti, R

    2014-03-06

    The combination of amino acids in their deprotonated and thus anionic form with a choline cation gives origin to a new and potentially important class of organic ionic compounds. A series of such neutral ion pairs has been investigated by first principle methods. The results reveal intriguing structural motives as well as regular patterns in the charge distribution and predict a number of vibrational and optical properties that could guide the experimental investigation of these compounds. The replacement of choline with its phosphocholine analogue causes the spontaneous reciprocal neutralization of cations and anions, taking place through the transfer of a proton between the two ions. Systems of this kind, therefore, provide a wide and easily accessible playground to probe the ionic/polar transition in organic systems, while the easy transfer of H(+) among neutral and ionic species points to their potential application as proton conductors. The analysis of the ab initio data highlights similarities as well as discrepancies from the rigid-ions force-field picture and suggests directions for the improvement of empirical models.

  1. Thermal and structural study on the lattice compound 1,4-diammoniumbutane bis(theophyllinate)

    Energy Technology Data Exchange (ETDEWEB)

    Ban, Margit; Madarasz, Janos; Bombicz, Petra; Pokol, Gyoergy; Gal, Sandor

    2004-10-01

    Crystalline title compound (1) prepared from aqueous solution of theophylline and 1,4-diaminobutane has been structurally and thermally characterized. Both the two-step TG decomposition curve and elemental analysis of the hexagonal crystals show that it consists of theophylline and 1,4-diaminobutane in 2:1 molar ratio. Actually, presence of one type of both theophyllinate anions and 1,4-diammoniumbutane dication have been indicated by FTIR spectroscopy. The molecular structure of lattice compound (1) has been determined by single crystal X-ray diffraction, where the hydrogen positions have been obtained from differential Fourier maps. It has confirmed that the crystal is really built up from these ionic constituents bound together with an extensive net of hydrogen bonds. The coupled TG-FTIR analysis of the evolved gases has revealed that the diamine is released as a whole molecule in the first decomposition step. Clathrate 1 and the proton migration in it might serve as a structural model of solid aminophylline whose crystal structure is still unknown.

  2. Study of Thermodynamic Properties of Nonstoichiometric Phase with Compound Energy Model

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Using compound energy model (CEM), the thermodynamic properties of and were evaluated.The evaluation was based on the optimization of ZrO2-CeO2 and ZrO2-CeO1.5 systems, as well as the miscibility gap inCeO1.5-CeO2 system. Except the cubic fluorite structure phase assessed with compound energy model, all the other solutionphases were assessed with subsitutional solution model. The model parameters were evaluated through fitting the selectedexperimental data by means of thermodynamic optimization. A set of parameters with thermodynamics self-consistency wasobtained and satisfactorily described the complex relation between y in and the partial pressure of oxygen atdifferent temperatures, also the interdependence among miscellaneous factors such as temperature, oxygen partial pressure,seem to be reasonable when put into the explanation of pressureless sintering of CeO2-stabilized ZrO2 powder compacts at acontrolled oxygen partial pressure.

  3. N-Nitroso compounds and childhood brain tumors: a case-control study.

    Science.gov (United States)

    Preston-Martin, S; Yu, M C; Benton, B; Henderson, B E

    1982-12-01

    We questioned mothers of 209 young brain tumor patients and mothers of 209 controls about experiences of possible etiological relevance which they had during pregnancy or which their children had while growing up. Long-suspected brain tumor risk factors such as head trauma and X-rays appeared to be factors for relatively few cases. Increased risk was associated with maternal contact with nitrosamine-containing substances such as burning incense (odds ratio, 3.3; p = 0.005), sidestream cigarette smoke (odds ratio, 1.5; p = 0.03), and face makeup (odds ratio, 1.6; p = 0.02); with maternal use of diuretics (odds ratio, 2.0; p = 0.03) and antihistamines (odds ratio, 3.4; p = 0.002); and with the level of maternal consumption of cured meats (p = 0.008). These drugs contain nitrosatable amines and amides, and the cured meats contain nitrites, chemicals which are precursors of N-nitroso compounds. We propose a hypothesis that brain tumors in these young people are related to in utero exposure to N-nitroso compounds and their precursors, the most potent nervous system carcinogens known in experimental animals.

  4. Feasibility study of heavy-ion beams and compound target materials for muon production

    Science.gov (United States)

    Sohn, Jae Bum; Lee, Ju Hahn; Kim, Gi Dong; Kim, Yong Kyun

    2015-10-01

    We have investigated the feasibility of using compound materials as targets for muon production by virtue of simulations using a GEANT4 toolkit. A graphite material and two thermostable compound materials, beryllium oxide (BeO) and boron carbide (B4C), were considered as muon production targets, and their muon production rates for a 600-MeV proton beam were calculated and compared. For the thermal analysis, the total heat deposited on the targets by the proton beams and the secondary particles was calculated with the MCNPX code; then, the temperature distribution of target was derived from the calculated heat by using the ANSYS code with consideration of heat transfer mechanisms such as thermal conduction and thermal radiation. In addition, we have investigated whether the heavy-ion beams can be utilized for muon production. For various beam species such as 3He2, 4He, 7Li, 10B and 12C, their muon production rates were calculated and compared with the rates experimentally-obtained for a proton beam.

  5. Comparative study of phenolic compounds and antioxidant activity in different species of cherries.

    Science.gov (United States)

    Liu, Yun; Liu, Xinyan; Zhong, Fei; Tian, Rongrong; Zhang, Kaichun; Zhang, Xiaoming; Li, Tianhong

    2011-05-01

    A new spectrometric method ultra performance liquid chromatography-tandem mass spectrometric with high precision and rapid analysis was developed to separate 17 phenolic compounds. Different species of cherries, including 10 sweet cherry (Prunus avium L.) cultivars, a tart cherry (P. cerasus L.) rootstock (CAB), and a hybrid rootstock 'Colt' (P. avium × P. pseudocerasus), were analyzed for phenolics contents by this method. The results showed that significant differences were observed among the phenolic compound contents in different cherry species. In 10 sweet cherry cultivars, the contents of neochlorogenic acid and cyanidin-3O-rutinoside were much higher in red-colored fruits (for example, 64.60 and 44.50 mg/100 g fresh weight in Burlat, respectively) than those in bicolored ones. Principal component analysis revealed that cyanidin-3O-rutinoside was an effective index for grouping the cultivars with similar species and fruit colors. Moreover, there were strong positive correlations between phenolics content and antioxidant activity, which was higher in red-colored cherries.

  6. Structural stability and magnetism of metastable Ni-Pt intermetallic compounds studied by ab initio calculation

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The self-consistent electronic structure calculations were carried out with the accurate frozen-core full-potential projector augmented-wave method on 13 Ni-Pt intermetallic compounds of simple crystalline structures,i.e. A15,D019,D03 and L12 Ni3Pt and NiPt3,and α-NiAs,B1,B2,L2a,and L10 NiPt. The calculations reveal that the L12 Ni3Pt,L10 NiPt and L12 NiPt3 are energetically more stable than their respective competitive structures,indicating that the three structures may be formed in some appropriate conditions. The obtained results match well with the experimental observation or other theory predictions. It is found that there is hybridization between Ni 3d and Pt 5d states,which may significantly affect the structural stability and magnetism of metastable Ni-Pt intermetallic compounds.

  7. Theoretical study of elastic, mechanical and thermodynamic properties of MgRh intermetallic compound

    Directory of Open Access Journals (Sweden)

    S. Boucetta

    2014-03-01

    Full Text Available In the last years, Magnesium alloys are known to be of great technological importance and high scientific interest. In this work, density functional theory plane-wave pseudo potential method, with local density approximation (LDA and generalized gradient approximation (GGA are used to perform first-principles quantum mechanics calculations in order to investigate the structural, elastic and mechanical properties of the intermetallic compound MgRh with a CsCl-type structure. Comparison of the calculated equilibrium lattice constant and experimental data shows good agreement. The elastic constants were determined from a linear fit of the calculated stress–strain function according to Hooke's law. From the elastic constants, the bulk modulus B, shear modulus G, Young's modulus E, Poisson's ratio σ, anisotropy factor A and the ratio B/G for MgRh compound are obtained. The sound velocities and Debye temperature are also predicted from elastic constants. Finally, the linear response method has been used to calculate the thermodynamic properties. The temperature dependence of the enthalpy H, free energy F, entropy S, and heat capacity at constant volume Cv of MgRh crystal in a quasi-harmonic approximation have been obtained from phonon density of states and discussed for the first report. This is the first quantitative theoretical prediction of these properties.

  8. Elastic and mechanical properties of Mg3Rh intermetallic compound: An ab initio study

    Directory of Open Access Journals (Sweden)

    S. Boucetta

    2016-06-01

    Full Text Available In this work, density functional theory plane-wave pseudo potential method, with local density approximation (LDA and generalized gradient approximation (GGA are used to investigate the structural, elastic, mechanical and thermodynamic properties of the intermetallic compound Mg3Rh. Comparison of the calculated equilibrium lattice constants and experimental data shows very good agreement. The elastic constants were determined from a linear fit of the calculated stress-strain function according to Hooke's law. From the elastic constants, the bulk modulus B, shear modulus G, Young's modulus E, Poisson's ratio σ, anisotropy factor A, the ratio B/G and the hardness parameter H for Mg3Rh compound are obtained. Our calculated elastic constants indicate that the ground state structure of Mg3Rh is mechanically stable. The calculation results show that this intermetallic crystal is stiff, elastically anisotropic and ductile material. The sound velocities and Debye temperature are also predicted from elastic constants. This is the first quantitative theoretical prediction of these properties.

  9. Studies on interaction of insect repellent compounds with odorant binding receptor proteins by in silico molecular docking approach.

    Science.gov (United States)

    Gopal, J Vinay; Kannabiran, K

    2013-12-01

    The aim of the study was to identify the interactions between insect repellent compounds and target olfactory proteins. Four compounds, camphor (C10H16O), carvacrol (C10H14O), oleic acid (C18H34O2) and firmotox (C22H28O5) were chosen as ligands. Seven olfactory proteins of insects with PDB IDs: 3K1E, 1QWV, 1TUJ, 1OOF, 2ERB, 3R1O and OBP1 were chosen for docking analysis. Patch dock was used and pymol for visualizing the structures. The interactions of these ligands with few odorant binding proteins showed binding energies. The ligand camphor had showed a binding energy of -136 kcal/mol with OBP1 protein. The ligand carvacrol interacted with 1QWV and 1TUJ proteins with a least binding energy of -117.45 kcal/mol and -21.78 kcal/mol respectively. The ligand oleic acid interacted with 1OOF, 2ERB, 3R1O and OBP1 with least binding energies. Ligand firmotox interacted with OBP1 and showed least binding energies. Three ligands (camphor, oleic acid and firmotox) had one, two, three interactions with a single protein OBP1 of Nilaparvatha lugens (Rice pest). From this in silico study we identified the interaction patterns for insect repellent compounds with the target insect odarant proteins. The results of our study revealed that the chosen ligands showed hydrogen bond interactions with the target olfactory receptor proteins.

  10. A novel aromatic oil compound inhibits microbial overgrowth on feet: a case study

    Directory of Open Access Journals (Sweden)

    Misner Bill D

    2007-07-01

    Full Text Available Abstract Background Athlete's Foot (Tinea pedis is a form of ringworm associated with highly contagious yeast-fungi colonies, although they look like bacteria. Foot bacteria overgrowth produces a harmless pungent odor, however, uncontrolled proliferation of yeast-fungi produces small vesicles, fissures, scaling, and maceration with eroded areas between the toes and the plantar surface of the foot, resulting in intense itching, blisters, and cracking. Painful microbial foot infection may prevent athletic participation. Keeping the feet clean and dry with the toenails trimmed reduces the incidence of skin disease of the feet. Wearing sandals in locker and shower rooms prevents intimate contact with the infecting organisms and alleviates most foot-sensitive infections. Enclosing feet in socks and shoes generates a moisture-rich environment that stimulates overgrowth of pungent both aerobic bacteria and infectious yeast-fungi. Suppression of microbial growth may be accomplished by exposing the feet to air to enhance evaporation to reduce moistures' growth-stimulating effect and is often neglected. There is an association between yeast-fungi overgrowths and disabling foot infections. Potent agents virtually exterminate some microbial growth, but the inevitable presence of infection under the nails predicts future infection. Topical antibiotics present a potent approach with the ideal agent being one that removes moisture producing antibacterial-antifungal activity. Severe infection may require costly prescription drugs, salves, and repeated treatment. Methods A 63-y female volunteered to enclose feet in shoes and socks for 48 hours. Aerobic bacteria and yeast-fungi counts were determined by swab sample incubation technique (1 after 48-hours feet enclosure, (2 after washing feet, and (3 after 8-hours socks-shoes exposure to a aromatic oil powder-compound consisting of arrowroot, baking soda, basil oil, tea tree oil, sage oil, and clove oil. Conclusion

  11. Teaching compound words to a spelling-disabled child via Smart Notebook Technology: Α case study approach

    Directory of Open Access Journals (Sweden)

    Styliani N. Tsesmeli

    2015-10-01

    Full Text Available The case-study aims to examine the effectiveness of training of morphological structure on the spelling of compounds by a spelling-disabled primary school student. The experimental design of the intervention was based on the word-pair paradigm and included a pre-test, a training program and a post-test (n= 50 pairs. The Training Program aimed to offer systematic, targeted and step-by-step instruction of morphological decomposition of words to the student and delivered via the Smart Notebook educational software. The intervention had a substantial impact in enhancing the spelling of compounds by the individual. Especially, instructional gains were statistically significant, and generalized substantially to untrained but analogous words and pseudowords in terms of structure and common stems. These findings are particularly important for the development of alternative approaches to the educational interventions of individuals with spelling difficulties and developmental dyslexia, and are consistent with the experimental literature.

  12. Application of a Pyroprobe-Deuterium NMR System: Deuterium Tracing and Mechanistic Study of Upgrading Process for Lignin Model Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ben, Haoxi; Jarvis, Mark W.; Nimlos, Mark R.; Gjersing, Erica L.; Sturgeon, Matthew R.; Foust, Thomas D.; Ragauskas, Arthur J.; Biddy, Mary J.

    2016-04-21

    In this study, a pyroprobe-deuterium (2H) NMR system has been used to identify isotopomer products formed during the deuteration and ring opening of lignin model compounds. Several common model compounds for lignin and its upgraded products, including guaiacol, syringol, toluene, p-xylene, phenol, catechol, cyclohexane, methylcyclohexane, and methylcyclopentane, have been examined for selective ring opening. Similar pathways for upgrading of toluene and p-xylene has been found, which will undergo hydrogenation, methyl group elimination, and ring opening process, and benzene, cyclohexane, and methylcyclohexane have been found as major intermediates before ring opening. Very interestingly, the 2H NMR analysis for the deuterium-traced ring opening of catechol on Ir/..gamma..-Al2O3 is almost identical to the ring opening process for phenol. The ring opening processes for guaiacol and syringol appeared to be very complicated, as expected. Benzene, phenol, toluene, cyclohexane, and methylcyclohexane have been determined to be the major products.

  13. Theoretical studies on a series of 1,2,4-triazoles derivatives as potential high energy density compounds

    Indian Academy of Sciences (India)

    Zhang Rui-Zhou; Li Xiao-Hong; Zhang Xian-Zhou

    2012-09-01

    Density functional theory calculations at B3LYP/6-31G∗∗ and B3P86/6-31G∗∗ levels were performed to predict the densities (), detonation velocities (D), pressures (P) and the thermal stabilities for a series of 1,2,4-triazole derivatives for looking high energy density compounds (HEDCs). The heats of formation (HOFs) are also calculated via designed isodesmic reactions. The calculations on the bond dissociation energies (BDEs) indicate that the position of the subsitutent group has great effect on the BDE and the BDEs of the initial scission step are between 31 and 65 kcal/mol. In addition, the condensed phase heats of formation are also calculated for the title compounds. These results would provide basic information for further studies of HEDCs.

  14. Electronic and optical properties of (U,Th)O2 compound from screened hybrid density functional studies

    Science.gov (United States)

    Mo, Chongjie; Yang, Yu; Kang, Wei; Zhang, Ping

    2016-04-01

    The electronic structure and optical properties for the (U,Th)O2 compound are systematically studied by employing the Heyd-Scuseria-Ernzerh method (HSE) of screened hybrid density functional. The electronic band gap of (U,Th)O2 is predicted to be 3.06 eV, in the middle of the values of UO2 and ThO2. Based on wavefunction analysis, we conclude (U,Th)O2 to be a Mott insulator in its ground state. The frequency dependent dielectric functions and optical properties are then calculated and compared with those of ThO2 and UO2. At the visible light frequency range, the adsorption coefficients for ThO2, UO2 and (U,Th)O2 are totally different, which gives an accessible method to predict the proportion of U atoms in an arbitrary unknown (U,Th)O2 compounds from the adsorption spectrum of visible lights.

  15. A case study involving allergic reactions to sulfur-containing compounds including, sulfite, taurine, acesulfame potassium and sulfonamides.

    Science.gov (United States)

    Stohs, Sidney J; Miller, Mark J S

    2014-01-01

    A case study is reported whereby an individual with known sulfite and sulfonamide allergies develops hypersensitivity to taurine above a threshold level as well as to the non-nutritive sweetener acesulfame potassium, compounds that are not normally associated with allergic reactions. Sulfites, sulfonamides, taurine and acesulfame potassium all contain a SO3 moiety. Challenge tests provide evidence for the hypersensitivities to taurine and acesulfame potassium. The subject is also allergic to thiuram mix and thimerosal, sulfur containing compounds, as well as to various food products. This may be the first case where hypersensitivities to taurine and acesulfame potassium have been documented and reported. Several mechanistic explanations are provided for the untoward reactions to taurine and acesulfame potassium. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Design of L21-type antiferromagnetic semiconducting full-Heusler compounds: A first principles DFT + GW study

    Science.gov (United States)

    Tas, M.; Şaşıoǧlu, E.; Friedrich, C.; Blügel, S.; Galanakis, I.

    2017-02-01

    Antiferromagnetic spintronics is an on-going growing field of research. Employing both standard density functional theory and the GW approximation within the framework of the full-potential linearized augmented-plane-wave method, we study the electronic and magnetic properties of seven potential antiferromagnetic semiconducting Heusler compounds with 18 (or 28 when Zn is present) valence electrons per unit cell. We show that in these compounds G-type antiferromagnetism is the ground state and that they are all either semiconductors (Cr2ScP, Cr2TiZn, V2ScP, V2TiSi, and V3Al) or semimetals (Mn2MgZn and Mn2NaAl). The many-body corrections have a minimal effect on the electronic band structure with respect to the standard electronic structure calculations.

  17. Breads enriched with guava flour as a tool for studying the incorporation of phenolic compounds in bread melanoidins.

    Science.gov (United States)

    Alves, Genilton; Perrone, Daniel

    2015-10-15

    In the present study we aimed at studying, for the first time, the incorporation of phenolic compounds into bread melanoidins. Fermentation significantly affected the phenolics profile of bread doughs. Melanoidins contents continuously increased from 24.1 mg/g to 71.9 mg/g during baking, but their molecular weight decreased at the beginning of the process and increased thereafter. Enrichment of white wheat bread with guava flour increased the incorporation of phenolic compounds up to 2.4-fold. Most phenolic compounds showed higher incorporation than release rates during baking, leading to increases from 3.3- to 13.3-fold in total melanoidin-bound phenolics. Incorporation patterns suggested that phenolic hydroxyls, but not glycosidic bonds of melanoidin-bound phenolics are cleaved during thermal processing. Antioxidant capacity of bread melanoidins increased due to enrichment with guava flour and increasing baking periods and was partially attributed to bound phenolics. Moreover, FRAP assay was more sensitive to measure this parameter than TEAC assay.

  18. Morphological constraints in children's spoken language comprehension: a visual world study of plurals inside compounds in English.

    Science.gov (United States)

    Silva, Renita; Gerth, Sabrina; Clahsen, Harald

    2013-11-01

    Many previous studies have shown that the human language processor is capable of rapidly integrating information from different sources during reading or listening. Yet, little is known about how this ability develops from child to adulthood. To gain insight into how children (in comparison to adults) handle different kinds of linguistic information during on-line language comprehension, the current study investigates a well-known morphological phenomenon that is subject to both structural and semantic constraints, the plurals-in-compounds effect, i.e. the dislike of plural (specifically regular plural) modifiers inside compounds (e.g. rats eater). We examined 96 seven-to-twelve-year-old children and a control group of 32 adults measuring their eye-gaze changes in response to compound-internal plural and singular forms. Our results indicate that children rely more upon structural properties of language (in the present case, morphological cues) early in development and that the ability to efficiently integrate information from multiple sources takes time for children to reach adult-like levels. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Experimental Study on Vehicle Integration of a Compound Regeneration System for Diesel Particulate Filter

    Science.gov (United States)

    Zi, Xinyun; Zhang, Weifeng; Yao, Guangtao; Xu, Zhengfei; He, Jinyong

    A compound regeneration system has shown potential in DPF regeneration. The system consists of FBC, burner and DOC to adapt to high sulfur in China. An aging test of 60,000 km and environmental compatibility test in cold zone, tropical zone and plateau is carried out, with the system integrated on Foton BJ1049V9JD6-SB light duty diesel. Statistics show aging of DPF promotes filtration efficiency because of microstructure change. Both DOC and engine aging are important elements of HC and CO increase. The working effect in cold zone and tropical zone and adaptability of regeneration device in plateau are discussed. The results reflect strong adaptability of regeneration device and discover the main difficulty for system application, which refers to overproof emissions due to aged DOC.

  20. Process engineering versus product engineering - A case study on volatile organic compounds removal

    DEFF Research Database (Denmark)

    Coutinho, João A.P.; Vilela, T.; Pereira, P.

    2005-01-01

    to the problem-need specified in the beginning of the project, but producing a novel formulation (chemical product design) represents a method that results to a completely xylene-free process which is environmentally and economically more interesting than those generated via the more traditional process......Three solutions for removing the dangerous volatile organic compound (VOC) xylene from an industrial coating process are presented and compared. Two of them are based on classical process engineering principles, i.e., development of separation-cleaning methods such as incineration and adsorption....... The last approach is somewhat different and is based on the so-called product engineering concept, i.e., in this case, a change of the formulation so that xylene is entirely eliminated from the process. It is shown that both the process and the product engineering approaches yield viable solutions...

  1. Determination of cetirizine in tablets and compounded capsules: comparative study between CE and HPLC

    Directory of Open Access Journals (Sweden)

    Lisiane Bajerski

    2010-01-01

    Full Text Available A capillary electrophoresis (CE method was developed and validated for determination of cetirizine dihydrochloride in tablets and compounded capsules. The electrophoretic separation was performed in an uncoated fused-silica capillary (40 cm x 50 μm i.d. using 20 mmol L-1 sodium tetraborate buffer (pH 9.3 as background electrolyte, a hydrodinamic sample injection at 50 mBar for 5 s, 20 KV applied voltage at 25 °C, and detection at 232 nm. The proposed method was compared with the high performance liquid chromatographic (HPLC method previously validated for this drug, and statistical analysis showed no significant difference between the techniques.

  2. Rb-intercalated C{sub 60} compounds studied by photoemission spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Brambilla, A. [INFM - Dipartimento di Fisica, Politecnico di Milano, p.za L. da Vinci 32, I-20133 Milan (Italy)]. E-mail: alberto.brambilla@polimi.it; Giovanelli, L. [Sincrotrone Trieste S.C.p.A., Strada Statale 14, Km 163.5, I-34012 Basovizza, Trieste (Italy); Vilmercati, P. [Sincrotrone Trieste S.C.p.A., Strada Statale 14, Km 163.5, I-34012 Basovizza, Trieste (Italy); Cattoni, A. [INFM - Dipartimento di Fisica, Politecnico di Milano, p.za L. da Vinci 32, I-20133 Milan (Italy); Biagioni, P. [INFM - Dipartimento di Fisica, Politecnico di Milano, p.za L. da Vinci 32, I-20133 Milan (Italy); Goldoni, A. [Sincrotrone Trieste S.C.p.A., Strada Statale 14, Km 163.5, I-34012 Basovizza, Trieste (Italy); Finazzi, M. [INFM - Dipartimento di Fisica, Politecnico di Milano, p.za L. da Vinci 32, I-20133 Milan (Italy); Duo, L. [INFM - Dipartimento di Fisica, Politecnico di Milano, p.za L. da Vinci 32, I-20133 Milan (Italy)

    2005-06-15

    We report on a combined photoemission and inverse photoemission spectroscopy analysis on Rb{sub x}C{sub 60} compounds with different stoichiometries (0-bar x-bar 6). Apart from shifts and broadening of the spectral features associated to the different phase formed, we observe in the RbC{sub 60} phase the presence of the highest occupied molecular orbital (HOMO) shoulder and of its symmetric (with respect to the Fermi level) empty state. According to calculations, the metallicity of this phase and the presence of these electronic states may be taken as a fingerprint of the interplay between electron-electron and electron-phonon interactions in determining the electronic behavior of alkali metal fullerides.

  3. Comparative study on the pharmacokinetics of inorganic and organic iron compounds in broiler chickens

    Directory of Open Access Journals (Sweden)

    Dimitrichka Dimitrova

    2014-03-01

    Full Text Available The pharmacokinetics of ferrous methionate and ferrous sulphate was investigated in broiler chickens after intravenous injection and crop intubation. The iron compounds were injected intravenously in v. brachialis. After 20-day “wash-out” period the ferrous methionate and ferrous sulphate were administered again by an elastic silicone tube into the crop. The serum concentrations of the iron were determined with bioanalyser. Two pharmacokinetic approaches were used – compartmental and non-compartmental analysis. After i.v. injection we found statistically significantly longer and better distribution of the iron contained in the ferrous methionate compared to the ferrous sulphate. The АUC0→∞ was statistically significantly higher in the ferrous methionate. In the alimentary tract of broiler chickens, ferrous methionate was absorbed more rapidly than ferrous sulfate. It was also distributed at a higher volume as compared to the ferrous sulfate.

  4. Neutron diffraction studies of nanoparticle RMnO{sub 3} compounds (R=Pr, Nd)

    Energy Technology Data Exchange (ETDEWEB)

    Baran, S., E-mail: stanislaw.baran@uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, PL-30 059 Kraków (Poland); Dyakonov, V. [Institute of Physics, PAS, Al. Lotników 32/46, PL-02-668 Warszawa (Poland); A. A. Gałkin Donetsk Physico-Technical Institute, National Academy of Sciences of Ukraine, 72 R. Luxembourg Str., Donetsk 83114 (Ukraine); Hofmann, T.; Hoser, A. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner Platz 1, D-14 109 Berlin (Germany); Penc, B. [M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, PL-30 059 Kraków (Poland); Kravchenko, Z. [A. A. Gałkin Donetsk Physico-Technical Institute, National Academy of Sciences of Ukraine, 72 R. Luxembourg Str., Donetsk 83114 (Ukraine); Szytuła, A. [M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, PL-30 059 Kraków (Poland)

    2013-10-15

    The neutron diffraction measurements of the nano-size RMnO{sub 3} (R=Pr, Nd) manganites have been performed. The obtained results indicate that these compounds crystallize in the orthorhombic crystal structure described by the space group Pnma. Low temperature data indicate both the absence of a long-range magnetic order down to 1.5 K in the PrMnO{sub 3} sample annealed at 800 °C and the C{sub x}F{sub y} magnetic structure with a very low value of the Mn magnetic moment as compared with bulk sample in the sample annealed at 900 °C. In the NdMnO{sub 3} samples annealed at 850 °C and 900 °C the magnetic order is described by the C{sub x}F{sub y} mode in the Mn sublattice and the F{sub y} mode in the Nd sublattice. The values of the Mn and Nd magnetic moments are lower that those in a bulk sample. Based on the model proposed in López-Quintela et al. [1] and Balcells et al. [2] the thickness of nonmagnetic shell was determined to be 7.1(4) nm in PrMnO{sub 3} and 4.6(5) nm in both the NdMnO{sub 3} compounds. - Highlights: • Magnetic structures of nanoparticle RMnO{sub 3} (R = Pr, Nd) samples have been determined. • The results have been compared with those obtained for polycrystalline samples. • According to the model in Refs. [1,2] the thickness of nonmagnetic shell has been found.

  5. Electronic structure studies of ferro-pnictide superconductors and their parent compounds using angle-resolved photoemission spectroscopy (ARPES)

    Energy Technology Data Exchange (ETDEWEB)

    Setti, Thirupathaiah

    2011-07-14

    The discovery of high temperature superconductivity in the iron pnictide compound LaO{sub 1-x}F{sub x}FeAs with T{sub c} = 26 K as created enormous interest in the high-T{sub c} superconductor community. So far, four prototypes of crystal structures have been found in the Fe-pnictide family. All four show a structural deformation followed or accompanied by a magnetic transition from a high temperature paramagnetic conductor to a low temperature antiferromagnetic metal whose transition temperature T{sub N} varies between the compounds. Charge carrier doping, isovalent substitution of the As atoms or the application of pressure suppresses the antiferromagnetic spin density wave (SDW) order and leads to a superconducting phase. More recently high Tc superconductivity has been also detected in iron chalchogenides with similar normal state properties. Since superconductivity is instability of the normal state, the study of normal state electronic structure in comparison with superconducting state could reveal important information on the pairing mechanism. Therefore, it is most important to study the electronic structure of these new superconductors, i.e., to determine Fermi surfaces and band dispersions near the Fermi level at the high symmetry points in order to obtain a microscopic understanding of the superconducting properties. Using the technique angle-resolved photoemission spectroscopy (ARPES) one measures the electrons ejected from a sample when photons impinge on it. In this way one can map the Fermi surface which provides useful information regarding the physics behind the Fermi surface topology of high T{sub c} superconductors. Furthermore, this technique provides information on the band dispersion, the orbital character of the bands, the effective mass, the coupling to bosonic excitations, and the superconducting gap. This emphasizes the importance of studying the electronic structure of the newly discovered Fe-pnictides using ARPES. In this work we have

  6. Studies of the Effectiveness of Bisphosphonate and Vanadium-Bisphosphonate Compounds In Vitro against Axenic Leishmania tarentolae

    Science.gov (United States)

    Christensen, Amy T.; McLauchlan, Craig C.; Dolbecq, Anne; Mialane, Pierre; Jones, Marjorie A.

    2016-01-01

    Leishmaniasis is a disease that is a significant problem for people, especially in tropical regions of the world. Current drug therapies to treat the disease are expensive, not very effective, and/or of significant side effects. A series of alkyl bisphosphonate compounds and one amino bisphosphonate compound, as well as alendronate and zoledronate, were tested as potential agents against Leishmania tarentolae. Also, two polyoxometalates (POMs) with nitrogen-containing bisphosphonate ligands, vanadium/alendronate (V5(Ale)2) and vanadium/zoledronate (V3(Zol)3), were tested against L. tarentolae and compared to the results of the alendronate and zoledronate ligands alone. Of the compounds evaluated in this study, the V5(Ale)2 and V3(Zol)3 complexes were most effective in inhibiting the growth of L. tarentolae. The V5(Ale)2 complex had a larger impact on cell growth than either alendronate or orthovanadate alone, whereas zoledronate itself has a significant effect on cell growth, which may contribute to the activity of the V3(Zol)3 complex. PMID:27034744

  7. Comparative study on gamma irradiation and cold plasma pretreatment for a cellulosic substrate modification with phenolic compounds

    Science.gov (United States)

    Irimia, Anamaria; Ioanid, Ghiocel Emil; Zaharescu, Traian; Coroabă, Adina; Doroftei, Florica; Safrany, Agnes; Vasile, Cornelia

    2017-01-01

    The efficiency of the activation of the cellulose/chitin mix substrate by cold plasma or γ-radiation exposure in order to modify it with bioactive compounds was studied. The eugenol or vegetable oils such as grape seed oil and rosehip seed oil have been grafted onto activated substrate. The examination of modified cellulose/chitin mix substrate by ATR-FTIR spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy confirms that the structural and morphological changes took place in both cases. The grafting degrees of the surface layer estimated from XPS data varied from 31.1% to 58.7% for air cold plasma activation and from 9.7% to 22.8% for γ-irradiation treatment. They depend both on bioactive compound used and procedure of substrate activation. Higher grafting degree are obtain by using vegetable oils than in the case of modification with eugenol and the air cold plasma activation seems to be much efficient than γ-irradiation. By grafting the polymeric substrate with bioactive compounds, antimicrobial and antioxidant properties have been conferred. Such materials can be considered promising for food packaging applications and medical textiles and also the applied procedures are environmental friendly ones.

  8. Ab initio study of doping effects in the 42214 compounds: A new family of layered iron-based superconductors

    Science.gov (United States)

    Bucci, F.; Sanna, A.; Profeta, G.; Continenza, A.; Gross, E. K. U.

    2017-01-01

    We present a systematic DFT-GGA theoretical characterization of the RE4Fe2As2Te1 -xO4 -yFy family of compounds (conventionally called 42214) as a function of a set of key tuning parameters: rare earth (RE = Pr, Sm, and Gd), Te content, oxygen → fluorine substitutional doping, and external pressure. We focus our discussion on the effect of these parameters on magnetic stability and on the nonmagnetic electronic structure, as most relevant aspects related to the occurrence of superconductivity. To uncover the complexity of the 42214 crystal structure, the electronic analysis is based on an unfolding procedure that allows us to observe the behavior of the hole and electron pockets of the Fermi surface and of the nesting function. We complete the present study with the characterization of a related hypothetical compound having Se substituting for Te. Our results show that this peculiar compound family offers very good opportunities to properly harness material properties; based on our results, we infer that suitably tuning a variety of parameters, as those examined here, improved superconducting properties could be achieved.

  9. Neurotoxic Effects of Platinum Compounds: Studies in vivo on Intracellular Calcium Homeostasis in the Immature Central Nervous System

    Directory of Open Access Journals (Sweden)

    Graziella Bernocchi

    2015-06-01

    Full Text Available Platinum compounds cause significant clinical neurotoxicity. Several studies highlight neurological complications especially in paediatric oncology patients with Central Nervous System (CNS and non-CNS malignancies. To understand the toxicity mechanisms of platinum drugs at cellular and molecular levels in the immature brain, which appears more vulnerable to injury than in the adult one, we compared the effects in vivo of the most used platinum compounds, i.e., cisdichlorodiammineplatinum (cisplatin, cisPt, and the new [Pt(O,O′-acac(γ-acac(DMS] (PtAcacDMS. As models of developing brain areas, we have chosen the cerebellum and hippocampus dentate gyrus. Both areas show the neurogenesis events, from proliferation to differentiation and synaptogenesis, and therefore allow comparing the action of platinum compounds with DNA and non-DNA targets. Here, we focused on the changes in the intracellular calcium homeostasis within CNS architecture, using two immunohistochemical markers, the calcium buffer protein Calbindin and Plasma Membrane Calcium ATPase. From the comparison of the cisPt and PtAcacDMS effects, it emerges how essential the equilibrium and synergy between CB and PMCA1 is or how important the presence of at least one of them is to warrant the morphology and function of nervous tissue and limit neuroarchitecture damages, depending on the peculiar and intrinsic properties of the developing CNS areas.

  10. Adsorption isotherm studies of chromium (VI) from aqueous solutions using sol-gel hydrotalcite-like compounds.

    Science.gov (United States)

    Ramos-Ramírez, Esthela; Ortega, Norma L Gutiérrez; Soto, Cesar A Contreras; Gutiérrez, Maria T Olguín

    2009-12-30

    In under-developed countries, industries such as paint and pigment manufacturing, leather tanning, chrome plating and textile processing, usually discharge effluents containing Cr(VI) and Cr(III) into municipal sanitary sewers. It has been reported that Cr(VI) acts as a powerful epithelial irritant and as a human carcinogen. In the present work, hydrotalcite-like compounds with a Mg/Al ratio=2 were synthesized by the sol-gel method. The hydrotalcite-like compounds and their corresponding thermally treated products were characterized by powder X-ray diffraction, infrared spectroscopy and N(2) adsorption. The hydrotalcite-like compounds and the heated solids were used as adsorbents for Cr(VI) in aqueous solutions. Adsorption isotherm studies of Cr(VI) from aqueous solution are described. The adsorbent capacity was determined using the Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherm models. The Cr(VI) adsorption isotherm data fit best to the Langmuir isotherm model. The maximum Cr(VI) uptake by hydrotalcite and the heated solids was determined using the Langmuir equation and was found to range between 26 and 29 mg Cr(VI)/g adsorbent.

  11. Mössbauer studies of the peculiar magnetism in parent compounds of the iron-based superconductors

    Science.gov (United States)

    Jasek, A. K.; Komędera, K.; Błachowski, A.; Ruebenbauer, K.; Żukrowski, J.; Bukowski, Z.; Karpinski, J.

    2015-02-01

    A review of the magnetism in the parent compounds of the iron-based superconductors is given based on the transmission Mössbauer spectroscopy of 57Fe and 151Eu. It was found that the 3d magnetism is of the itinerant character with varying admixture of the spin-polarized covalent bonds. For the '122' compounds, a longitudinal spin density wave (SDW) develops. In the case of the EuFe2As2, a divalent europium arranges in an anti-ferromagnetical order at a much lower temperature as compared with the onset of SDW. These two magnetic systems remain almost uncoupled one to another. For the non-stoichiometric Fe1+xTe parent of the '11' family, one has a transversal SDW and magnetic order of the interstitial iron with relatively high and localized magnetic moments. These two systems are strongly coupled one to another. For the 'grand parent' of the iron-based superconductors FeAs, one observes two mutually orthogonal phase-related transversal SDW on the iron sites. There are two sets of such spin arrangements due to two crystallographic iron sites. The FeAs exhibits the highest covalency among the compounds studied, but it has still a metallic character. A contribution to XVI National Conference on Superconductivity, Zakopane, Poland, 7-12 October 2013.

  12. Hybrid Hamiltonian and Green's Function Approach for Studying Native Point Defect Levels in Semiconductor Compounds and Superlattices

    Science.gov (United States)

    Krishnamurthy, Srini; Van Orden, Derek; Yu, Zhi-Gang

    2016-09-01

    We have developed a hybrid method that can be applied to study isolated defects in semiconductor compounds and superlattices. The method is a combination of (1) a long-range tight-binding (TB) Hamiltonian, (2) a first-principles Hamiltonian, and (3) a Green's function (GF) formalism. The calculation of the GF requires accurate energy band structure, wave functions, and defect potentials. The TB Hamiltonian with sp 3 orbitals basis ensures accurate band gaps and band masses while providing the functional form for the wave functions. We calculated the band gaps of InAs/GaSb and InAs/InAsSb strained-layer superlattices and found them to agree well with measurements. The change in potentials caused by native point defects (NPDs) was obtained from a first-principles method using Spanish Initiative for Electronic Simulations with Thousands of Atoms, which also uses sp 3 basis. We describe the method of calculating NPD energy levels in compounds and superlattices, obtain some defect levels in GaAs, InAs, InSb, and GaSb compounds, and provide details of the NPD-level calculations.

  13. Study on material base and action mechanism of compound Danshen dripping pills for treatment of atherosclerosis based on modularity analysis.

    Science.gov (United States)

    Zhou, Wei; Yuan, Wen-Feng; Chen, Chao; Wang, Shu-Mei; Liang, Sheng-Wang

    2016-12-04

    Traditional Chinese medicine (TCM) has been widely used in China and its surrounding countries in clinical treatments for centuries-long time. However, due to the complexity of TCM constituents, both action mechanism and material base of TCM remain nearly unknown. The present study was designed to uncover the action mechanism and material base of TCM in a low-cost manner. Compound Danshen dripping pills (DSP) is a widely used TCM for treatment of atherosclerosis, and was researched here to demonstrate the effectiveness of our method. We constructed a heterogeneous network for DSP, identified the significant network module, and analyzed the primary pharmacological units by performing GO and pathways enrichment analysis. Two significant network modules were identified from the heterogeneous network of DSP, and three compounds out of four hub nodes in the network were found to intervene in the process of atherosclerosis. Moreover, 13 out of 20 enriched pathways that were ranked in top 10 corresponding to both the two pharmacological units were found to be involved in the process of atherosclerosis. Quercetin, luteolin and apigenin may be the main active compounds which modulate the signaling pathways, such as metabolism of xenobiotics by cytochrome P450, retinol metabolism, etc. The present method helps reveal the action mechanism and material base of DSP for treatment of atherosclerosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. Studies of the Effectiveness of Bisphosphonate and Vanadium-Bisphosphonate Compounds In Vitro against Axenic Leishmania tarentolae

    Directory of Open Access Journals (Sweden)

    Amy T. Christensen

    2016-01-01

    Full Text Available Leishmaniasis is a disease that is a significant problem for people, especially in tropical regions of the world. Current drug therapies to treat the disease are expensive, not very effective, and/or of significant side effects. A series of alkyl bisphosphonate compounds and one amino bisphosphonate compound, as well as alendronate and zoledronate, were tested as potential agents against Leishmania tarentolae. Also, two polyoxometalates (POMs with nitrogen-containing bisphosphonate ligands, vanadium/alendronate (V5(Ale2 and vanadium/zoledronate (V3(Zol3, were tested against L. tarentolae and compared to the results of the alendronate and zoledronate ligands alone. Of the compounds evaluated in this study, the V5(Ale2 and V3(Zol3 complexes were most effective in inhibiting the growth of L. tarentolae. The V5(Ale2 complex had a larger impact on cell growth than either alendronate or orthovanadate alone, whereas zoledronate itself has a significant effect on cell growth, which may contribute to the activity of the V3(Zol3 complex.

  15. Genome-wide fitness test and mechanism-of-action studies of inhibitory compounds in Candida albicans.

    Directory of Open Access Journals (Sweden)

    Deming Xu

    2007-06-01

    Full Text Available Candida albicans is a prevalent fungal pathogen amongst the immunocompromised population, causing both superficial and life-threatening infections. Since C. albicans is diploid, classical transmission genetics can not be performed to study specific aspects of its biology and pathogenesis. Here, we exploit the diploid status of C. albicans by constructing a library of 2,868 heterozygous deletion mutants and screening this collection using 35 known or novel compounds to survey chemically induced haploinsufficiency in the pathogen. In this reverse genetic assay termed the fitness test, genes related to the mechanism of action of the probe compounds are clearly identified, supporting their functional roles and genetic interactions. In this report, chemical-genetic relationships are provided for multiple FDA-approved antifungal drugs (fluconazole, voriconazole, caspofungin, 5-fluorocytosine, and amphotericin B as well as additional compounds targeting ergosterol, fatty acid and sphingolipid biosynthesis, microtubules, actin, secretion, rRNA processing, translation, glycosylation, and protein folding mechanisms. We also demonstrate how chemically induced haploinsufficiency profiles can be used to identify the mechanism of action of novel antifungal agents, thereby illustrating the potential utility of this approach to antifungal drug discovery.

  16. Effect of chemical degradation on fluxes of reactive compounds – a study with a stochastic Lagrangian transport model

    Directory of Open Access Journals (Sweden)

    J. Rinne

    2012-06-01

    Full Text Available In the analyses of VOC fluxes measured above plant canopies, one usually assumes the flux above canopy to equal the exchange at the surface. Thus one assumes the chemical degradation to be much slower than the turbulent transport. We used a stochastic Lagrangian transport model in which the chemical degradation was described as first order decay in order to study the effect of the chemical degradation on above canopy fluxes of chemically reactive species. With the model we explored the sensitivity of the ratio of the above canopy flux to the surface emission on several parameters such as chemical lifetime of the compound, friction velocity, stability, and canopy density. Our results show that friction velocity and chemical lifetime affected the loss during transport the most. The canopy density had a significant effect if the chemically reactive compound was emitted from the forest floor. We used the results of the simulations together with oxidant data measured during HUMPPA-COPEC-2010 campaign at a Scots pine site to estimate the effect of the chemistry on fluxes of three typical biogenic VOCs, isoprene, α-pinene, and β-caryophyllene. Of these, the chemical degradation had a major effect on the fluxes of the most reactive species β-caryophyllene, while the fluxes of α-pinene were affected during nighttime. For these two compounds representing the mono- and sesquiterpenes groups, the effect of chemical degradation had also a significant diurnal cycle with the highest chemical loss at night. The different day and night time loss terms need to be accounted for, when measured fluxes of reactive compounds are used to reveal relations between primary emission and environmental parameters.

  17. Development of an in vitro model for the simultaneous study of the efficacy and hematotoxicity of antileukemic compounds.

    Science.gov (United States)

    Valeri, Antonio; Alonso-Ferrero, María Eugenia; Cerrato, Laura; Martínez, Sandra; Bueren, Juan A; Albella, Beatriz

    2010-12-15

    Hematopoietic system displays a wide spectrum of cell populations hierarchically organized in the bone marrow. Homeostasis in this system requires equilibrium between the self-renewal of the stem cells and their capacity of differentiation. Any failure on this equilibrium could lead to fatal consequences, such as the development of leukemia. Due to its rapid rate of renewal, hematopoietic tissue is a major target for antitumoral compounds and often becomes a dose limiting factor in the development of antineoplastics. Our aim was to develop an in vitro model for predicting the efficacy of antitumoral compounds on leukemic cells and their toxic effects on the healthy hematopoietic cells. The mouse myelomonocytic leukemia WEHI-3b was transduced with a lentiviral vector for expressing the green fluorescence protein. Mixed semisolid clonogenic cultures of transduced WEHI-3b and murine bone marrow cells were exposed to five pharmaceuticals: daunorubicin (positive control), atropine sulphate (negative control) and three in different stages of clinical development (trabectedin, Zalypsis(®) and PM01183). Colonies of leukemic cells were distinguishable from healthy CFU-GM under fluorescence microscope. The sensitivity of leukemic cells to daunorubicin, trabectedin, Zalypsis(®) and PM01183 was higher compared to healthy cells. The effect of a non-antitumoral compound, atropine sulphate, was the same on both populations. Our results show that this in vitro model is a valuable tool for studying the effect of antitumoral compounds in both tumoral and normal hematopoietic cells under the same toxic microenvironment and could safe time and facilitate the reduction of the number of animals used in preclinical development of pharmaceuticals.

  18. A search for pure compounds suitable for use as matrix in spectroscopic studies of radiation-produced radical cations. III. A selection of compounds based on the thermochemistry of hydrogen and proton transfer reactions between neutral molecules and their cations

    Science.gov (United States)

    Van den Bosch, Ann; Ceulemans, Jan

    A systematic investigation is made of the thermochemistry of hydrogen and proton transfer between neutral molecules and their cations covering the entire organic chemistry, with the aim of selecting those compounds that are suitable for use as matrices in spectroscopic studies of radiation-produced radical cations. Compounds that are characterized by positive reaction enthalpies may be considered promising for use as matrices in such studies. Calculations are based on experimentally determined ionization energies and proton affinities and on carbon-hydrogen bond strengths that are arbitrarily taken as 418 kJ.mol -1 (100 kcal.mol -1). Effects of actual deviations from this value are considered. In the aliphatic series of compounds, reaction enthalpies depend strongly on functional groups present. Marked positive reaction enthalpies are obtained for alkenes, alkadienes, thioethers, mercaptans, iodoalkanes and tertiary amines. Non-aromatic cyclic compounds generally behave as their aliphatic counterparts. Thus, positive reaction enthalpies are generally obtained for unsaturated alicyclic hydrocarbons and cyclic thioethers. Positive reaction enthalpies are also obtained for piperidine, quinuclidine, manxine and derivatives. In the homocyclic aromatic series of compounds, reaction enthalpies are generally positive. Thus, positive reaction enthalpies are obtained for aromatic hydrocarbons, fluoro- and chlorobenzenes, aromatic amines (amino group attached directly to the ring) and halo- and methoxyanilines. In the heterocyclic aromatic series of compounds reaction enthalpies are generally negative. This is for instance the case for a large number of pyridine derivatives, di- and triazines and a number of bi- and tricyclic compounds. Positive reaction enthalpies are however obtained for furan and pyrrole.

  19. The effectiveness of sublingual and topical compounded bioidentical hormone replacement therapy in postmenopausal women: an observational cohort study.

    Science.gov (United States)

    Ruiz, Andres D; Daniels, Kelly R

    2014-01-01

    Prior studies demonstrated improved menopausal symptom relief following treatment with compounded bioidentical hormone replacement therapy; however, clinical effectiveness studies evaluating different routes of bioidentical hormone replacement therapy administration are lacking. The objective of this study was to determine the effectiveness of sublingual and topical compounded bioidentical hormone replacement therapy for the treatment of vasomotor, mood, and other quality-of-life symptoms in post-menopausal women. This was a prospective, observational cohort study of women > or = 18 years of age who received a compounded sublingual or topical bioidentical hormone replacement therapy preparation between January 1, 2003 and October 1, 2010 in a community pharmacy. Data collection included patient demographics, comorbidities, hormone regimens, and therapeutic outcomes. Patients rated their vasomotor, mood, and quality-of-life symptoms as absent, mild, moderate, or severe at baseline, at one to three months follow-up, and three to six months follow-up. Baseline characteristics were compared using the chi-square test for categorical variables and the Wilcoxon rank sum test for continuous variables. Symptom intensity between baseline and follow-up periods were compared using the Wilcoxon signed-rank test. A total of 200 patients met study criteria; 160 received topical bioidentical hormone replacement therapy, and 40 received sublingual bioidentical hormone replacement therapy. Most sublingually-treated patients (70%) received an estrogen combination and 100% received progesterone. Nearly half (43%) of the topically treated patients received an estrogen combination (43%) and 99% received progesterone. The percentage of sublingually treated patients reporting "moderate" or "severe" symptoms was significantly reduced at one to three months follow-up for the following target symptoms: hot flashes (31%, P = 0.04), night sweats (38%, P sublingual bioidentical hormone

  20. Assessing and Managing the Risks of Fuel Compounds: Ethanol Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Layton, D.W.; Rice, D.W.

    2002-02-04

    We have implemented a suite of chemical transport and fate models that provide diagnostic information about the behavior of ethanol (denoted EtOH) and other fuel-related chemicals released to the environment. Our principal focus is on the impacts to water resources, as this has been one of the key issues facing the introduction of new fuels and additives. We present analyses comparing the transport and fate of EtOH, methyl tertiary butyl ether (MTBE), and 2,2,4 trimethyl pentane (TMP) for the following cases (1) discharges to stratified lakes, subsurface release in a surficial soil, (3) cross-media transfer from air to ground water, and (4) fate in a regional landscape. These compounds have significantly different properties that directly influence their behavior in the environment. EtOH, for example, has a low Henry's law constant, which means that it preferentially partitions to the water phase instead of air. An advantageous characteristic of EtOH is its rapid biodegradation rate in water; unlike MTBE or TMP, which degrade slowly. As a consequence, EtOH does not pose a significant risk to water resources. Preliminary health-protective limits for EtOH in drinking water suggest that routine releases to the environment will not result in levels that threaten human health.

  1. Natural compounds involved in adipose tissue mass control in in vitro studies

    Directory of Open Access Journals (Sweden)

    Katarzyna Kowalska

    2011-08-01

    Full Text Available The World Health Organization (WHO has recognized obesity as an epidemic of the 21st century. Obesity is pathological fat accumulation in the body influenced by many factors: metabolic, endocrine, genetic, environmental, psychological and behavioral. The quality and quantity of food intake to a considerable degree determine excessive fat accumulation in the body. The strategy in obesity prevention includes, among other things, a proper diet. It is widely known that a diet rich in fruits and vegetables reduces body weight. Adipocytes are not only cells serving as storage depots for “energy”, but are also specialized cells influenced by various hormones, cytokines and nutrients, which have pleiotropic effects on the body. Knowledge of adipocyte biology is crucial for our understanding of the pathophysiological basis of obesity and metabolic diseases, such as type 2 diabetes. Furthermore, rational manipulation of adipose physiology is a promising avenue for therapy of these conditions. Adipose tissue mass can be reduced through elimination of adipocytes by apoptosis, inhibition of adipogenesis and increased lipolysis in adipocytes. Natural products have a potential to induce apoptosis, inhibit adipogenesis and stimulate lipolysis in adipocytes. Various dietary bioactive compounds target different stages of the adipocyte life cycle and may be useful as natural therapeutic agents in obesity prevention.

  2. [Study on control and management for industrial volatile organic compounds (VOCs) in China].

    Science.gov (United States)

    Wang, Hai-Lin; Zhang, Guo-Ning; Nei, Lei; Wang, Yu-Fei; Hao, Zheng-Ping

    2011-12-01

    Volatile organic compounds (VOCs) emitted from industrial sources account for a large percent of total anthropogenic VOCs. In this paper, VOCs emission characterization, control technologies and management were discussed. VOCs from industrial emissions were characterized by high intensity, wide range and uneven distribution, which focused on Bejing-Tianjin Joint Belt, Shangdong Peninsula, Yangtze River Delta and the Pearl River Delta. The current technologies for VOCs treatment include adsorption, catalytic combustion, bio-degradation and others, which were applied in petrochemical, oil vapor recovery, shipbuilding, printing, pharmaceutical, feather manufacturing and so on. The scarcity of related regulations/standards plus ineffective supervision make the VOCs management difficult. Therefore, it is suggested that VOCs treatment be firstly performed from key areas and industries, and then carried out step by step. By establishing of actual reducing amount control system and more detailed VOCs emission standards and regulations, applying practical technologies together with demonstration projects, and setting up VOCs emission registration and classification-related-charge system, VOCs could be reduced effectively.

  3. Structural, electronic, and elastic properties of K-As compounds: a first principles study.

    Science.gov (United States)

    Ozisik, Havva Bogaz; Colakoglu, Kemal; Deligoz, Engin; Ozisik, Haci

    2012-07-01

    First-principle calculations are performed to investigate the structural, elastic and electronic properties of K-As compounds (KAs in NaP, LiAs and AuCu-type structures, KAs(2) in MgCu(2)-type structure, K(3)As in Na(3)As, Cu(3)P and Li(3)Bi-type structures, and K(5)As(4) in A(5)B(4)-type structure). The lattice parameters, cohesive energy, formation energy, bulk modulus, and the first derivative of bulk modulus (to fit to the Murnaghan's equation of state) of the considered structures are calculated and reasonable agreement is obtained, and the phase transition pressure is also predicted. The repeated calculations on the electronic band structures and the related partial density of states are also given. The calculated second-order elastic constants based on the stress-strain method and the other related quantities such as Young's modulus, shear modulus, Poisson's ratio, sound velocities, Debye temperature, and shear anisotropy factors for considered structures are presented, and trends are discussed.

  4. Feasibility studies of the growth of 3-5 compounds of boron by MOCVD

    Science.gov (United States)

    Manasevit, H. M.

    1988-01-01

    Boron-arsenic and boron-phosphorus films have been grown on Si sapphire and silicon-on-sapphire (SOS) by pyrolyzing Group 3 alkyls of boron, i.e., trimethylborane (TMB) and triethylborane (TEB), in the presence of AsH3 and PH3, respectively, in an H2 atmosphere. No evidence for reaction between the alkyls and the hydrides on mixing at room temperature was found. However, the films were predominantly amorphous. The film growth rate was found to depend on the concentration of alkyl boron compound and was essentially constant when TEB and AsH3 were pyrolyzed over the temperature range 550 C to 900 C. The films were found to contain mainly carbon impurities (the amount varying with growth temperature), some oxygen, and were highly stressed and bowed on Si substrates, with some crazing evident in thin (2 micron) B-P and thick (5 micron) B-As films. The carbon level was generally higher in films grown using TEB as the boron source. Films grown from PH3 and TMB showed a higher carbon content than those grown from AsH3 and TMB. Based on their B/As and B/P ratios, films with nominal compositions B sub12-16 As2 and B sub1.1-1.3 P were grown using TMB as the boron source.

  5. Benzoic Acid and Chlorobenzoic Acids: Thermodynamic Study of the Pure Compounds and Binary Mixtures With Water.

    Science.gov (United States)

    Reschke, Thomas; Zherikova, Kseniya V; Verevkin, Sergey P; Held, Christoph

    2016-03-01

    Benzoic acid is a model compound for drug substances in pharmaceutical research. Process design requires information about thermodynamic phase behavior of benzoic acid and its mixtures with water and organic solvents. This work addresses phase equilibria that determine stability and solubility. In this work, Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) was used to model the phase behavior of aqueous and organic solutions containing benzoic acid and chlorobenzoic acids. Absolute vapor pressures of benzoic acid and 2-, 3-, and 4-chlorobenzoic acid from literature and from our own measurements were used to determine pure-component PC-SAFT parameters. Two binary interaction parameters between water and/or benzoic acid were used to model vapor-liquid and liquid-liquid equilibria of water and/or benzoic acid between 280 and 413 K. The PC-SAFT parameters and 1 binary interaction parameter were used to model aqueous solubility of the chlorobenzoic acids. Additionally, solubility of benzoic acid in organic solvents was predicted without using binary parameters. All results showed that pure-component parameters for benzoic acid and for the chlorobenzoic acids allowed for satisfying modeling phase equilibria. The modeling approach established in this work is a further step to screen solubility and to predict the whole phase region of mixtures containing pharmaceuticals.

  6. Neuroprotective compounds and innovative therapeutic strategies for Parkinson’s disease: experimental and clinical studies

    Directory of Open Access Journals (Sweden)

    Fabio Blandini

    2009-09-01

    Full Text Available Fabio BlandiniInterdepartmental Research Center for Parkinson’s Disease (CRIMP, IRCCS Neurological Institute “C. Mondino Foundation”, Pavia, ItalyAbstract: Identifying new therapeutic strategies capable of modifying the course of Parkinson’s disease (PD is currently one of the major goals for the researchers of this field. Various mechanistic definitions have been proposed to describe the hypothetical ability of a therapeutic intervention to prevent, block or reverse the neurodegenerative process underlying PD. The general term “neuroprotection” has been related to the capacity of interfering with the ongoing process of neuronal cell death, in order to slow or halt disease progression, while a term such as “neurorestoration” would apply to any intervention capable of increasing the number of surviving dopaminergic neurons. Although none of the therapeutic approaches tested in PD patients has so far shown the ability to stop or reverse disease progression, a certain degree of neuroprotection can be achieved with compounds that are already available in the pharmacological armamentarium of the neurologist. Treatment with dopamine agonists or MAO-B inhibitors, particularly when started in the very early phases of the disease, may play disease-modifying effects and even L-DOPA, at low doses, may be slightly neuroprotective. For a true neurorestorative intervention, promising perspectives are being provided by neurotrophic factors and stem cells, which, however, still need to unveil their full potential.Keywords: L-DOPA, dopamine agonists, MAO-B inhibitors, trophic factors, stem cells

  7. Study of resolution enhancement methods for impurities quantitative analysis in uranium compounds by XRF

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Clayton P.; Salvador, Vera L.R.; Cotrim, Marycel E.B.; Pires, Maria Ap. F.; Scapin, Marcos A., E-mail: clayton.pereira.silva@usp.b [Instituto de Pesquisas Energeticas e Nucleares (CQMA/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Quimica e Meio Ambiente

    2011-07-01

    X-ray fluorescence analysis is a technique widely used for the determination of both major and trace elements related to interaction between the sample and radiation, allowing direct and nondestructive analysis. However, in uranium matrices these devices are inefficient because the characteristic emission lines of elements like S, Cl, Zn, Zr, Mo and other overlap characteristic emission lines of uranium. Thus, chemical procedures to separation of uranium are needed to perform this sort of analysis. In this paper the deconvolution method was used to increase spectra resolution and correct the overlaps. The methodology was tested according to NBR ISO 17025 using a set of seven certified reference materials for impurities present in U3O8 (New Brunswick Laboratory - NBL). The results showed that this methodology allows quantitative determination of impurities such as Zn, Zr, Mo and others, in uranium compounds. The detection limits were shorter than 50{mu}g. g{sup -1} and uncertainty was shorter than 10% for the determined elements. (author)

  8. A Comparative Study of the Formation of Aromatics in Rich Methane Flames Doped by Unsaturated Compounds

    CERN Document Server

    Gueniche, Hadj-Ali; Glaude, Pierre-Alexandre; Fournet, René; Battin-Leclerc, Frédérique; 10.1016/j.fuel.2009.03.006

    2009-01-01

    For a better modeling of the importance of the different channels leading to the first aromatic ring, we have compared the structures of laminar rich premixed methane flames doped with several unsaturated hydrocarbons: allene and propyne, because they are precursors of propargyl radicals which are well known as having an important role in forming benzene, 1,3-butadiene to put in evidence a possible production of benzene due to reactions of C4 compounds, and, finally, cyclopentene which is a source of cyclopentadienylmethylene radicals which in turn are expected to easily isomerizes to give benzene. These flames have been stabilized on a burner at a pressure of 6.7 kPa (50 Torr) using argon as dilutant, for equivalence ratios (?) from 1.55 to 1.79. A unique mechanism, including the formation and decomposition of benzene and toluene, has been used to model the oxidation of allene, propyne, 1,3 butadiene and cyclopentene. The main reaction pathways of aromatics formation have been derived from reaction rate and ...

  9. Synthesis, characterization, thermal and computational studies of novel tetra-azido compounds as energetic plasticizers

    Science.gov (United States)

    Baghersad, Mohammad Hadi; Habibi, Azizollah; Heydari, Akbar

    2017-02-01

    In this paper, four azido compounds have been synthesized and characterized as new energetic plasticizers. Nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy, elemental analysis, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and differential thermal analysis (DTA) have been used to identify and determine the properties of the synthesized plasticizers. The plasticization effect of plasticizers on glycidyl azide polymer (GAP) has been investigated by viscosity measurements and thermal analysis of the prepolymer-plasticizer mixtures and plasticized binders. The plasticized mixtures were cured by a diisocyanate curing agent and the glass transition temperature and decomposition temperature of the cured polyurethane binders were measured. Thermal analysis of the prepolymer-plasticizer and cured polymer mixtures showed that the synthesized plasticizers are completely compatible with the GAP binder and have a very good plasticizing effect. Furthermore, equilibrium geometry and heats of formation of each of the plasticizer molecules were obtained using the thermochemical T1 recipe, which is available in wave function Spartan software. Comparing empirical heats of combustion and calculated heats of combustion by using the heats of formation showed that the suggested optimum molecular structure by the T1 recipe has a high similarity to the real molecular structure of these molecules.

  10. X-ray and DFT Study of Glaucocalyxin A Compound with Cytotoxic Activity

    Institute of Scientific and Technical Information of China (English)

    Fu-dong Wang; Tao Wang; An-an Wu; Lan Ding; Han-qing Wang

    2009-01-01

    The title compound glaucocalyxin A (1) (Tα,14β-dihydroxy-ent-kaur-16-en-3,15-dione) iso-lated from the leaves of isodon excisoides was characterized by IR, 1H NMR, 13C NMR, 1H-1H COSY, HMQC, HMBC, and EIMS, and its crystal structure was determined by single-crystal X-ray diffraction. The X-ray crystal structure revealed that the molecular backbone of the chosen crystal is a tetracyclic system, including three six-membered rings and a five-membered ring, and the three six-membered rings are in a chair-like conformation. The five-membered ring adopts a twisted envelope-like conformation, and its geometrical param-eters were compared with theoretical calculations at the B3LYP and HF level of theory. The molecules form extensive networks through the intra- and intermolecular hydrogen bonds. The experimental NMR data were interpreted with the aid of magnetic shielding constant calculations, by means of the GIAO (gauge-Including atomic orbitals) method. Calculated and experimental results were compared with a satisfactory level of agreement. Molecular electrostatic potential map was used in an attempt to identify key features of the diterpenoid glaucocalyxin A that is necessary for its activity. Calculations of molecular electrostatic po-tential and stabilization energies suggest that the protonation of glaucocalyxin A will be able to occur on carbonyl oxygen atoms.

  11. Electronic magnetic structure of intermetallic compounds RNi2Mn studied by XMCD

    Science.gov (United States)

    Kuznetsova, Tatyana V.; Grebennikov, Vladimir I.; Gerasimov, E. G.; Mushnikov, N. V.

    2017-10-01

    The x-ray absorption near edge structure (XANES) and the x-ray magnetic circular dichroism (XMCD) measurements in the hard X-ray range at the Ni and Mn K edges and Tb, Dy L2, 3 edges were carried out in TbNi2Mn and DyNi2Mn in magnetic field up to 6 T at 10 K. XMCD on the Dy and Tb L-edges reaches 3.2%. The spin and orbital d-projected density of states on Tb and Dy atoms were obtained from the XMCD spectra. The Ni and Mn K-edges absorptions are practically identical in both compounds, as well as the dichroism spectra. The magnitude of dichroism is less than 0.5% and its length of about 50 eV. Scattering of outgoing p-wave on magnetic atoms environment is the main source of the K-edge dichroism. Element-specific magnetic hysteresis-loops measurements on TbNi2Mn and DyNi2Mn were performed by X-ray magnetic circular dichroism.

  12. Organolithium compounds catalyzed trimerization of nitriles and study on the catalystic charateristics%有机锂化合物催化合成均三嗪

    Institute of Scientific and Technical Information of China (English)

    李敏; 黄淑萍; 刘滇生; 李思殿

    2003-01-01

    The imine salt was formed initially by the addition of an organolithium compound to the aromatic nitricle. This type of reaction usually leads to cyclic products, such as triazines. We discussed the mechanism of organolithium compounds catalyzed trimerization of nitriles and study the catalystic charateristics. Using this new method, the yield of triazines was improved.

  13. Polybenzimidazole compounds

    Science.gov (United States)

    Klaehn, John R.; Peterson, Eric S.; Wertsching, Alan K.; Orme, Christopher J.; Luther, Thomas A.; Jones, Michael G.

    2010-08-10

    A PBI compound that includes imidazole nitrogens, at least a portion of which are substituted with an organic-inorganic hybrid moiety. At least 85% of the imidazole nitrogens may be substituted. The organic-inorganic hybrid moiety may be an organosilane moiety, for example, (R)Me.sub.2SiCH.sub.2--, where R is selected from among methyl, phenyl, vinyl, and allyl. The PBI compound may exhibit similar thermal properties in comparison to the unsubstituted PBI. The PBI compound may exhibit a solubility in an organic solvent greater than the solubility of the unsubstituted PBI. The PBI compound may be included in separatory media. A substituted PBI synthesis method may include providing a parent PBI in a less than 5 wt % solvent solution. Substituting may occur at about room temperature and/or at about atmospheric pressure. Substituting may use at least five equivalents in relation to the imidazole nitrogens to be substituted or, preferably, about fifteen equivalents.

  14. Study of the Gastroprotective Effect of Extracts and Semipurified Fractions of Chresta martii DC. and Identification of Its Principal Compounds

    Directory of Open Access Journals (Sweden)

    E. S. Franco

    2015-01-01

    Full Text Available Chresta martii (Asteraceae is a species widely used by the population of the Xingu region of Sergipe, Brazil, in the form of a decoction (aerial parts for the treatment of gastrointestinal diseases. The study aims to assess the gastroprotective activity of organic extracts and semipurified fractions and identify the principal compounds present in C. martii responsible for such activity. The organic extracts (cyclohexane: ECCm, ethyl acetate: EACm, and ethanol: EECm were obtained from the dried aerial parts (500 g of C. martii. For evaluation of the gastroprotective activity of extracts (50, 100, or 200 mg/kg; p.o., male Swiss Webster mice (25–30 g were used which had gastric ulcers induced by indomethacin (40 mg/kg, s.c. or ethanol (0.2 mL/animal; p.o.. Among the extracts evaluated, EACm exhibited significant (P<0.05 gastroprotective activity in the models used. The fractionation of EACm was performed in a silica gel column 60 eluted with the following compounds: [chloroform—F1 yield (10%], [chloroform/ethyl acetate (1/1—F2 yield (6%], [ethyl acetate—F3 yield (8%], and [ethyl/methanol acetate (1/1—F4 yield (5%]. Of the fractions described above, the F1 (25 mg/kg; p.o. had greater gastroprotective activity (P<0.05 than that displayed by ranitidine (80 mg/kg; p.o. in the ethanol-induced ulcer model. The refractionation of F1 produced 23 subfractions and from these two yellow amorphous compounds were obtained by recrystallization, Rf: 0.46 and 0.31 (ethyl acetate : chloroform 5 : 5. The compounds isolated were characterized by nuclear magnetic resonance spectroscopy (1H-NMR and 13C-NMR and identified as flavones: chrysoeriol (yield: 0.43% and 3′,4′-dimethoxyluteolin (yield: 0.58%. Conclusion. Flavone 3′,4′-dimethoxyluteolin is the principal compound present in the species C. martii and is probably responsible for gastroprotective activity observed in this species.

  15. Discodermolide--a new, marine-derived immunosuppressive compound. I. In vitro studies.

    Science.gov (United States)

    Longley, R E; Caddigan, D; Harmody, D; Gunasekera, M; Gunasekera, S P

    1991-10-01

    The in vitro immunosuppressive properties of a novel, marine-derived compound, discodermolide, are reported here. Discodermolide suppressed the proliferative responses of splenocytes in the murine two-way mixed lymphocyte reaction (MLR) and concanavalin A stimulated cultures, with IC50 values of 0.24 microM and 0.19 microM, respectively. There was no evidence of cytotoxicity for murine splenocytes at concentrations of discodermolide as high as 1.26 microM. Similarly, discodermolide suppressed the proliferative responses of human peripheral blood leukocytes (PBL) in the two-way MLR, and Con A and phytohemagglutinin mitogenesis. The IC50 values were 5.65 microM, 28.02 microM, and 30.12 microM for the MLR, Con A, and PHA mitogenic responses, respectively. There was no evidence of cytotoxicity toward human PBL at discodermolide concentrations as high as 80.64 microM. Discodermolide was equally effective, compared with cyclosporine, in suppressing the PMA-ionomycin induced proliferation of purified, murine T cells, with IC50 values of 9.0 nM and 14.0 nM for discodermolide and CsA, respectively. The production of IL-2 by PMA-ionomycin stimulated T cells was not inhibited by discodermolide; however, the percentage of IL-2 receptor-bearing cells as measured by immunofluorescence with 7D4 antibody, specific for the 55-kDa chain (p55) comprising the murine IL-2 receptor, was reduced. The expression of a similar chain comprising the human IL-2 receptor (Tac antigen, p55) by PHA or Con-A-stimulated PBL was similarly suppressed by discodermolide. The precise mechanism of action of discodermolide remains to be elucidated.

  16. Solution-reaction Calorimetric Study of Coordination Compounds of Rare Earth Perchlorates with Alanine and Imidazole

    Institute of Scientific and Technical Information of China (English)

    ZHAO, Yan-Ru(赵艳茹); HOU, An-Xin(侯安新); DONG, Jia-Xin(董家新); ZHAO, Shun-Sheng(赵顺省); LIU, Yi(刘义); QU, Song-Sheng(屈松生)

    2004-01-01

    Two coordination compounds of rare earth perchlorates with alanine and imidazole, [RE(Ala)n(Im)(H2O)](ClO4)3(s) (RE=La, n=3; RE=Nd, n=2), have been prepared and characterized. The standard molar enthalpies of reaction for the following two reactions, LaCL·7H2O(s)+3Ala(s)+Im(s)+3NaClO4(s)=[La(Ala).(Im)(H2O)]-(ClO4)3(s)+3NaCl(s)+6H2O(I)(1)and NdCl3·6H2O(s)+2Ala(s)+2Ala(s)+Im(s)+3NaClO4(s)=[Nd(Ala)2(Im)(H2O)]-(ClO4)3(s)+3NaCl(s)+5H2O(l) (2), were determined by solution-reaction calorimetry, at T=298.15 K, as 36.168 ±0.642kJ·mol-1 and 48.590±0.934kJ·mol-1 respectively. From the results and other auxiliary quantities, the standard molar enthalpies of formation of [La(Ala)3(Im)(H2O)](ClO4)3(s) and [Nd(Ala)2(Im)(H2O)] (ClO4)3(s) were derived,△fH(-)m{[La(Ala).(Im)(H2O)](ClO4)3,s}=(-2984.8±1.0)kJ·mol-1 and △fH(-)m{[Nd(Ala).(Im)(H2O)]-(ClO4)3,s}=(-2387.8±0.8)kJ·mol-1, respectively.

  17. [Study on volatile organic compounds emission of straw combustion and management countermeasure in Wuhan city].

    Science.gov (United States)

    Huang, Bi-Jie

    2013-12-01

    Straw combustion is an important anthropogenic source of volatile organic compounds (VOCs) in China. Emissions of VOCs from straw combustion significantly affect climate forcing and human health. A reliable estimation of VOCs emission from the source is the important prerequisite for emission impact assessment and control strategy in the urban or regional areas. VOCs emissions from straw combustion in Wuhan City and the districts were estimated by factor analysis method, which was based on the yield of major farm crops in the period of 2005-2011. Moreover, Cultivated-land Emission Intensity (Ie) and Regional Emission Intensity (Ir) were also calculated. VOCs Emissions from straw combustion in Wuhan City were (3,163 +/- 139) t in the period of 2005-2011; Ie and Ir was (1.52 +/- 0.06) t x km(-2) and (0.37 +/- 0.02) t x km(-2), respectively; Straw combustion of grain and oilseed crops was the main source of the emissions; 21 kinds of VOCs should be listed as the priority control pollutants for straw combustion in Wuhan City. The order of successively decreasing VOCs emission of districts in Wuhan City was Huangpi District, Xinzhou District, Jiangxia District, Caidian District, Hannan District, and Dongxihu District, the former 4 districts contributed to almost 90% VOCs emissions of the Wuhan City. Huangpi District, Xinzhou District, Jiangxia District, and Hannan District should be regarded as priority control areas of VOCs emission from straw combustion in Wuhan City. Much attention should be paid to Jiangxia District, which was nationally representative. Ie and Ir are important basic data for ecological risk assessment of some kind of pollutants emitted from straw combustion in the urban or regional areas. Furthermore, straw utilization model according to agricultural cyclic economy is a feasible way to cope with the environmental problem of straw combustion.

  18. Carcinogenicity studies on fibres, metal compounds, and some other dusts in rats.

    Science.gov (United States)

    Pott, F; Ziem, U; Reiffer, F J; Huth, F; Ernst, H; Mohr, U

    1987-01-01

    About 50 dusts were examined on their carcinogenicity in rats mainly after intraperitoneal injection and some after intratracheal instillation. In the i.p. test, very low doses between 0.05 and 0.5 mg asbestos led to tumour incidences of about 20 to 80%. Polyvinyl-pyridine-N-oxide prolonged the tumour latency after injection of actinolite. 60 mg attapulgite from three sources with short fibre lengths were not shown to be carcinogenic but an attapulgite sample with longer fibres had a moderate effect. Relatively thick rock and ceramic fibres (median greater than 1 micron) induced tumours, but slag and wollastonite fibres did not, probably because of their better solubility. Intratracheal instillations of glass microfibres (20 X 0.5 mg) led to lung tumours in 5 of 34 rats (0 in control). The carcinogenic potency of an inorganic fibre depends on its size and persistency, and possibly also on other properties, especially on the surface. Nickel powder, nickel oxide, nickel subsulfide and cadmium sulfide were all found to be carcinogenic in the two tests. Cadmium chloride and cadmium oxide could only be administered in very low doses because of their high acute toxicity. A high amount of magnetite (15 X 15 mg i.tr.) led to an unexpected lung tumour incidence of 69%. The i.p. test in rats proved to be very sensitive for detecting the carcinogenic potency of non-acute toxic natural and man-made mineral dusts as well as metal compounds. This means that, if a high dose of one of these dusts does not induce tumours in this test, no suspicion of carcinogenic potency can be substantiated.

  19. Isotopic composition of Murchison organic compounds: Intramolecular carbon isotope fractionation of acetic acid. Simulation studies of cosmochemical organic syntheses

    Science.gov (United States)

    Yuen, G. U.; Cronin, J. R.; Blair, N. E.; Desmarais, D. J.; Chang, S.

    1991-01-01

    Recently, in our laboratories, samples of Murchison acetic acid were decarboxylated successfully and the carbon isotopic composition was measured for the methane released by this procedure. These analyses showed significant differences in C-13/C-12 ratios for the methyl and carboxyl carbons of the acetic acid molecule, strongly suggesting that more than one carbon source may be involved in the synthesis of the Murchison organic compounds. On the basis of this finding, laboratory model systems simulating cosmochemical synthesis are being studied, especially those processes capable of involving two or more starting carbon sources.

  20. Computer simulation of the heavy-duty turbo-compounded diesel cycle for studies of engine efficiency and performance

    Science.gov (United States)

    Assanis, D. N.; Ekchian, J. A.; Heywood, J. B.; Replogle, K. K.

    1984-01-01

    Reductions in heat loss at appropriate points in the diesel engine which result in substantially increased exhaust enthalpy were shown. The concepts for this increased enthalpy are the turbocharged, turbocompounded diesel engine cycle. A computer simulation of the heavy duty turbocharged turbo-compounded diesel engine system was undertaken. This allows the definition of the tradeoffs which are associated with the introduction of ceramic materials in various parts of the total engine system, and the study of system optimization. The basic assumptions and the mathematical relationships used in the simulation of the model engine are described.

  1. Comparative study of the results of compound tibial shaft fractures treated by Ilizarov ring fixators and limb reconstruction system fixators

    Institute of Scientific and Technical Information of China (English)

    Chandra Prakash Pal; Harish Kumar; Deepak Kumar; K.S.Dinkar; Vivek Mittal; Naveen Kumar Singh

    2015-01-01

    Purpose: Ilizarov ring fixator and limb reconstruction system (LRS) fixators have been used in the management of complex tibial fractures with severe soft tissue injuries, compound tibial fractures, and infected tibial nonunion for which conventional internal fixation cannot be contemplated.Fracture union and distraction osteogenesis can be done simultaneously with these external fixators, allowing early weight bearing.Several previous studies have shown almost equal results of rail and ring fixators for the compound tibial shaft fractures.Thus we performed a prospective study to evaluate the union rate, functional outcome and amount of limb lengthening after the treatment of compound tibial shaft fractures with or without infected nonunion by ring or LRS fixators.Methods: This prospective study was done at Sarojini Naidu Medical College and Hospital, Agra, India and included 32 patients of compound tibial shaft fractures with or without infected nonunion.There were 26 males and 6 females and the average age was 40 years.Patients were randomly divided into two groups (n =16 for each): one underwent Ilizarov fixation and the other received LRS fixation.Cases were followed up for 3-24 months, 6 months on average from September 2012 to October 2014.Functional and radiological outcomes were assessed using the Association for the Study and Application of Methods of Ilizarov (ASAMI) criteria for both rail and ring fixators.Results: Union was achieved in all cases.Radiological outcome was found excellent in 68.75%, good in 18.75% and fair in 12.50% of cases treated by rail fixators whereas it was excellent in 56.25%, good in 18.75%, fair in 12.50% and poor in 12.50% of cases treated by ring fixators.Functional result was satisfactory in 75.00% of cases treated by rail fixator and 68.75% of cases treated by ring fixators whereas the corresponding rate of unsatisfactory was 25.00% vs.31.25%.Conclusion: In our short-term assessment, LRS fixators show a

  2. Study of Properties of Mixed Ferro-Ferrimagnetic Ising Compounds with (AxB1-x)yC

    Institute of Scientific and Technical Information of China (English)

    XINZi-Hua; WEIGuo-Zhu; LIANGYa-Qiu; ZHANGQi

    2004-01-01

    The magnetic properties of the mixed ferro-ferrimagnetic compounds with (AxB1-x)yC, where A, B,and C are three different magnetic ions and form three different sublattices, are studied by using the standardmean-field theory. The phase diagram which is related to experimental work of molecule-based ferro-ferrimagnet(NiⅡxMnⅡ1-x)1.5[CrⅢ(CN)6] · zH2O is obtained. The magnetization curves, internal energy, and specific heat of thesame mixed (AxB1-x)y C system are also investigated.

  3. Study of Properties of Mixed Ferro-Ferrimagnetic Ising Compounds with (AxB1-x)yC

    Institute of Scientific and Technical Information of China (English)

    XIN Zi-Hua; WEI Guo-Zhu; LIANG Ya-Qiu; ZHANG Qi

    2004-01-01

    The magnetic properties of the mixed ferro-ferrimagnetic compounds with (AxB1-x)yC, where A, B, and C are three different magnetic ions and form three different sublattices, are studied by using the standard mean-field theory. The phase diagram which is related to experimental work of molecule-based ferro-ferrimagnet (NiⅡxMn1Ⅱ-x)1.5[CrⅢ(CN)6]· zH2O is obtained. The magnetization curves, internal energy, and specific heat of the same mixed (Ax B1- x) y C system are also investigated.

  4. A CLINICAL STUDY TO EVALUATE THE ROLE OF AKSHITARPANA, SHIRODHARA AND AN AYURVEDIC COMPOUND IN CHILDHOOD COMPUTER VISION SYNDROME

    Directory of Open Access Journals (Sweden)

    Singh Omendra Pal

    2011-03-01

    Full Text Available Computer vision syndrome is one among the lifestyle disorders in children. About 88% of people who use computers everyday suffer from this problem and children are no exception. Computer Vision Syndrome (CVS is the complex of eye and vision problems related to near works which are experienced during the use of Video Display Terminals (TV and computers. Therefore, considering these prospects a randomized double blind placebo control study was conducted among 40 clinically diagnosed children (5-15 years age group of computer Vision Syndrome to evaluate the role of akshitarpana, shirodhara and an ayurvedic compound in childhood computer vision syndrome.

  5. A FOURIER TRANSFORM INFRARED SPECTROSCOPIC STUDY OF THE REACTION BETWEEN POLY (VINYL PYRIDINE)S AND EPOXY COMPOUNDS

    Institute of Scientific and Technical Information of China (English)

    XUE Gi; JIANG Shankeng

    1987-01-01

    Chemical reactions between poly (vinyl pyridine)s and 1,4-butanediol diglycidyl ether and other epoxy compounds were studied by Fouriertransform infrared spectroscopy and other techniques. The epoxy group was found to react with the pyridine side group of poly (4-vinyl pyridine), forming crosslinked networks which contain cyclic amide structures. The reaction was also observed in the interfacial region of poly(vinyl pyridine) and γ-glycidoxy propyl trimethoxysilane hydrolyzate (γ-GPS) coatings on PET fiber substrates.Poly(2-vinyl pyridine) does not show the same reaction.

  6. Study on the Built-up Effect of Inorganic Compounds to Flame Retardant Containing Organophosphorus in Suppression of Smoke

    Institute of Scientific and Technical Information of China (English)

    LIN Miao; XIAN Chun-ying; YANG Yong

    2006-01-01

    The built-up effect of inorganic compounds containing more active metal ions, such as Ca2+ , Al3+ , Cu2+ , and Zn2+ , as additives adding to phosphorus-containing flame retarding systems in suppression of smoke was studied. The data presented herein suggested that the amount of smoke in the burning process can be better suppressed after the cotton fabric finishing with built- up system was burnt. Some general principles were identified, and the likely causes of the observed effects were analyzed according to test data.

  7. Neutron scattering study on R{sub 2}PdSi{sub 3} (R=Ho,Er,Tm) compounds

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Fei

    2010-12-14

    Previous studies on the family of inter-metallic rare-earth compounds R{sub 2}PdSi{sub 3} revealed multifaceted magnetic properties, for instance, spin-glass like behavior. Experimental observations include: Signs of a crystallographic superstructure, complicated magnetic structures both in zero field and in applied magnetic fields as well as a generic phase in applied fields for compounds in the series with the heavy rare-earths R=Gd, Tb, Dy, Ho, Er and Tm. This thesis expands the studies on the magnetic properties of R{sub 2}PdSi{sub 3} employing mainly neutron scattering on single crystals with the focus on the compounds with R=Ho, Er and Tm. A detailed analysis of the crystallographic superstructure using modulation wave approach and group theory is presented. The resulting structure implies the existence of two different rare-earth sites with reduced symmetry and an arrangement of the different sites according to sequences as determined by the superstructure. It is shown that the reduced symmetry of the rare-earth sites is explicitly observed in the energy spectra of inelastic neutron scattering. The results on the magnetic structures and excitations are shown and discussed in the framework of the superstructure model. Specifically the generic phase in applied fields is interpreted as a direct consequence of the crystallographic superstructure. It is rather unusual that a crystallographic superstructure is playing such a decisive, and through the field dependence also tunable role in determining the magnetic properties as observed in R{sub 2}PdSi{sub 3}. The mediating interactions between the crystallographic part and the magnetic part of the system are discussed. (orig.)

  8. Extremotolerance and resistance of lichens: comparative studies on five species used in astrobiological research II. Secondary lichen compounds.

    Science.gov (United States)

    Meessen, J; Sánchez, F J; Sadowsky, A; de la Torre, R; Ott, S; de Vera, J-P

    2013-12-01

    Lichens, which are symbioses of a fungus and one or two photoautotrophs, frequently tolerate extreme environmental conditions. This makes them valuable model systems in astrobiological research to fathom the limits and limitations of eukaryotic symbioses. Various studies demonstrated the high resistance of selected extremotolerant lichens towards extreme, non-terrestrial abiotic factors including space exposure, hypervelocity impact simulations as well as space and Martian parameter simulations. This study focusses on the diverse set of secondary lichen compounds (SLCs) that act as photo- and UVR-protective substances. Five lichen species used in present-day astrobiological research were compared: Buellia frigida, Circinaria gyrosa, Rhizocarpon geographicum, Xanthoria elegans, and Pleopsidium chlorophanum. Detailed investigation of secondary substances including photosynthetic pigments was performed for whole lichen thalli but also for axenically cultivated mycobionts and photobionts by methods of UV/VIS-spectrophotometry and two types of high performance liquid chromatography (HPLC). Additionally, a set of chemical tests is presented to confirm the formation of melanic compounds in lichen and mycobiont samples. All investigated lichens reveal various sets of SLCs, except C. gyrosa where only melanin was putatively identified. Such studies will help to assess the contribution of SLCs on lichen extremotolerance, to understand the adaptation of lichens to prevalent abiotic stressors of the respective habitat, and to form a basis for interpreting recent and future astrobiological experiments. As most of the identified SLCs demonstrated a high capacity in absorbing UVR, they may also explain the high resistance of lichens towards non-terrestrial UVR.

  9. The Effect of Phosphatidylcholine and Deoxycholate Compound Injections to the Localized Adipose Tissue: An Experimental Study with a Murine Model

    Directory of Open Access Journals (Sweden)

    Yongjoon Noh

    2012-09-01

    Full Text Available Background Phosphatidylcholine (PPC and deoxycholate (DCA compound has been recentlyused for the purpose of partial lipolysis and is valued for its efficacy and lower invasivenesscompared to liposuction and dermolipectomy used previously. In this article, the authors discussthe efficacy of the PPC dissolved in DCA via an experimental rat study model, along with suggestinga useful animal experimental model for the study of adipose tissue and lipolysis.Methods Bilateral inguinal fat pads of an experimental rat were elevated with the deep inferiorepigastric vessel as the sole vascular pedicle. Normal saline was injected on one side as acontrol group and a PPC and DCA compound was injected on the other side. After 4 days, therats were euthanized for microscopic tissue examination. The pathology was scored by a semiquantitativesystem in 4 categories: normal fat amount, fat necrosis, inflammatory activity,and stage of fibrosis. A Wilcoxon signed-rank test powered by SPSS packet program was usedfor statistical analysis and to determine significance.Results Microscopic examination was performed on the obtained samples, and theexperimental data of all four categories showed significant histologic differences compared tothe control group. All of the data also showed statistical significance by the Wilcoxon signedranktest (P<0.01.Conclusions In the inguinal fat pad rat model, the control group and the experimental grouphad a differed significantly in the amount of normal fat tissue, inflammation, necrosis, andfibrosis. We recommend the rat inguinal fat pad model used in this study, as it is likely to beuseful in related research.

  10. Diverse anisotropy of phonon transport in two-dimensional group IV-VI compounds: A comparative study

    Science.gov (United States)

    Qin, Guangzhao; Qin, Zhenzhen; Fang, Wu-Zhang; Zhang, Li-Chuan; Yue, Sheng-Ying; Yan, Qing-Bo; Hu, Ming; Su, Gang

    2016-05-01

    New classes of two-dimensional (2D) materials beyond graphene, including layered and non-layered, and their heterostructures, are currently attracting increasing interest due to their promising applications in nanoelectronics, optoelectronics and clean energy, where thermal transport is a fundamental physical parameter. In this paper, we systematically investigated the phonon transport properties of the 2D orthorhombic group IV-VI compounds of GeS, GeSe, SnS and SnSe by solving the Boltzmann transport equation (BTE) based on first-principles calculations. Despite their similar puckered (hinge-like) structure along the armchair direction as phosphorene, the four monolayer compounds possess diverse anisotropic properties in many aspects, such as phonon group velocity, Young's modulus and lattice thermal conductivity (κ), etc. Especially, the κ along the zigzag and armchair directions of monolayer GeS shows the strongest anisotropy while monolayer SnS and SnSe show almost isotropy in phonon transport. The origin of the diverse anisotropy is fully studied and the underlying mechanism is discussed in details. With limited size, the κ could be effectively lowered, and the anisotropy could be effectively modulated by nanostructuring, which would extend the applications to nanoscale thermoelectrics and thermal management. Our study offers fundamental understanding of the anisotropic phonon transport properties of 2D materials, and would be of significance for further study, modulation and applications in emerging technologies.

  11. Realizing the recognition features of model antipsychotic compounds by important protein: Photochemical and computational studies.

    Science.gov (United States)

    Ding, Fei; Peng, Wei; Chao, Ming-Wei; Peng, Yu-Kui

    2015-07-01

    Phenothiazine and its derivatives are the most effective antipsychotic drugs. They have been used in the treatment of serious mental and emotional symptoms including bipolar disorder, organic psychoses, psychotic depression and schizophrenia. However, these drugs cause serious side effects such as akathisia, hyperprolactinaemia and neuroleptic malignant syndrome. In this work we investigated the molecular recognition of two typical phenothiazine compounds, phenosafranin and safranin O by the most pivotal heme protein hemoglobin using steady state and time-resolved fluorescence, extrinsic 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescent probe, circular dichroism (CD) along with computational modeling. Results show phenothiazines complex with protein via formation of adducts at 298 K with moderate strengths of 3.555×10(4) M(-1) and 2.567×10(4) M(-1) for the hemoglobin-phenosafranin and hemoglobin-safranin O, respectively. We also found phenothiazines were effectors at the protein allosteric site, which affects the allosteric equilibrium. Further, time-resolved fluorescence and hydrophobic ANS experiments showed the static mechanism is dominated for the shrinkage in the fluorescence intensity of β-37 Trp residue at the α1β2 interface. The stoichiometric proportion of the protein-drug adduct is 1:1, as derived from Job's plot. Several crucial noncovalent bonds, including hydrogen bonds, π-π stacking and hydrophobic interactions played a major role in stabilizing the noncovalent conjugates. Based on three-dimensional fluorescence, we concluded that the conformation of hemoglobin is partially destabilized after recognition with phenothiazines. These alterations were confirmed by far-UV CD spectra that showed the α-helix of protein decreased from 78.3% in free hemoglobin to 62.8% and 64.8% in hemoglobin-phenosafranin and hemoglobin-safranin O, respectively. Computer-aided molecular docking was consistent, indicating that both phenothiazines are situated

  12. Discodermolide--a new, marine-derived immunosuppressive compound. II. In vivo studies.

    Science.gov (United States)

    Longley, R E; Caddigan, D; Harmody, D; Gunasekera, M; Gunasekera, S P

    1991-10-01

    The in vivo immunosuppressive properties of a novel, marine-derived compound, discodermolide, are reported here. Discodermolide was effective in suppressing the graft-versus-host splenomegaly response of BALB/c----CB6F1 (BALB/c X C57BL/6J)F1 grafted mice at 5.0, 2.5, and 1.25 mg/kg, when administered as daily, i.p. injections, for 7 days. Mice treated with 5.0 and 2.5 mg/kg demonstrated a high degree of suppression (219 and 150%, respectively); however, these dosages were associated with some degree of morbidity (2/5 and 4/5 survivors for 5.0 and 2.5 mg/kg, respectively). Mice that were treated with 1.25, 0.625, and 0.313 mg/kg remained healthy after a 7-day regimen, and continued to demonstrate suppression of splenomegaly (106%, 72%, and 76% suppression, respectively). Splenocytes obtained from discodermolide-treated, allogeneic grafted mice were suppressed in their ability to respond in vitro to optimal mitogenic concentrations of concanavalin A, and natural-killer-cell activity directed against YAC-1 tumor cells, compared with vehicle-treated, allogeneic grafted control mice. Lower dosages (2.5 and 1.25 mg/kg) of discodermolide, however, did not affect the subsequent ability of splenocytes obtained from these mice to produce IL-2 following in vitro stimulation with Con A. This was observed to be in contrast to the immunosuppressive activity observed with cyclosporine treatment of mice (150 mg/kg) for the ex vivo suppression of splenocyte production of IL-2. Treatment of normal, nongrafted mice with similar high dosages of discodermolide (5.0 mg/kg) for 4 days did not affect the primary antibody response of mice immunized with sheep red blood cells as measured by hemagglutination activity of their serum. These results suggest that discodermolide's in vivo immunosuppressive action appears not to be that of a generalized immunosuppressive agent and that its specific in vivo mechanism of action warrants further preclinical evaluation.

  13. Study of the performance of three LC-MS/MS platforms for analysis of perfluorinated compounds

    Energy Technology Data Exchange (ETDEWEB)

    Llorca, Marta; Farre, Marinella [IDAEA-CSIC, Department of Environmental Chemistry, Barcelona (Spain); Pico, Yolanda [Universitat de Valencia, Laboratori de Nutricio i Bromatologia, Facultat de Farmacia, Burjassot, Valencia (Spain); Barcelo, Damia [IDAEA-CSIC, Department of Environmental Chemistry, Barcelona (Spain); King Saud University, Riyadh (Saudi Arabia)

    2010-10-15

    The analytical suitabilities of three different liquid chromatography-tandem mass spectrometry (LC-MS/MS) systems, (1) triple quadrupole (QqQ), (2) conventional 3D ion trap (IT), and (3) quadrupole-linear IT (QqLIT), to determine trace levels of perfluorinated compounds (PFCs) in fish and shellfish were compared. Sample preparation was performed using alkaline extraction and solid-phase-extraction cleanup. This evaluation was focused on both quantitative (sensitivity, precision, and accuracy) and qualitative (identification capabilities) aspects. In the three instruments, the former facet was evaluated using selected reaction monitoring (SRM), which is the standard mode for quantitative LC-MS/MS analysis. Accuracy was similar in the three systems, with recoveries always over 70 %. Precision was better for the QqLIT and QqQ systems (7-15%) than for the IT system (10-17%). The QqLIT (working in SRM mode) and QqQ systems offered a linear dynamic range of at least 3 orders of magnitude, whereas that of the IT system was 2 orders of magnitude. The QqLIT system achieved at least 20-fold higher sensitivity than the QqQ system, and this was at least tenfold higher sensitivity than for the IT system. In the IT system, identification was based on sensitive full mass range acquisition and MS{sup n} fragmentation and in the QqLIT system, it was based on the use of an information-dependent-acquisition scan function, which allows the combination of an SRM or MS full scan acting as the survey scan and an enhanced product ion scan followed by MS{sup 3} as the dependent scan in the same analysis. Three instruments were applied to monitor the content in fish and shellfish (anchovies, swordfish, tuna, mussels, and oysters) obtained from Valencia and Barcelona markets (Spain). The eight target PFCs were detected at mean concentrations in the range from 10 ng kg {sup -1} (perfluoro-7-methyloctanoic acid and perfluoro-1-decanesulfonate) to 4,200 ng kg {sup -1} (perfluoropentanoic acid

  14. Plasticization and Reinforcement in a Boron Cage Compound Polyurethane Nanocomposite: A Dielectric Study

    Energy Technology Data Exchange (ETDEWEB)

    Bowen, Dan; Liu, J.; Zhang, X.; Eastwood, E.; Bowler, N.

    2012-09-21

    In order to control and modify the physical properties of nanocomposite systems, it is essential to understand the nano-filler/polymer structure-property relationships. Boron cage compounds (BCCs) are a class of icosahedral, closed cage molecules that are of interest due to their high boron content and inherent neutron absorbing/shielding properties, and because of their ability to act as molecular nano-particles. When the BCC n-hexylcarborane is blended with a polybutadiene (PBD)/polyurethane (PU) segmented copolymer (EN8) an increase in the glass transition (Tg) temperature of the PBD phase (reinforcement) and a decrease in the Tg temperatures of the PU phases (plasticization) are observed. These observations were investigated by examining the dielectric relaxation properties of copolymer samples with and without added n-hexylcarborane (0wt% and 5wt% n-hexylcarborane) using broadband dielectric spectroscopy in the frequency range from 0.01 to 1 MHz and temperature range from -140 to 130 °C. Parametric fitting techniques aided in the identification of two α relaxation processes associated with the glass transitions of the soft PBD phase and the hard urethane phases, and a secondary β relaxation process due to the localized motions of side groups. The conductivities at low frequencies were also identified and modeled. Differential Scanning Calorimetry (DSC) did not indicate the presence of a crystalline component within the copolymer samples, so interfacial polarization (Maxwell-Wagner-Sillars) relaxation is not possible. A relaxation map (Arrhenius diagram) associated with these processes has been developed from the experimental data to elucidate the role of n-hexylcarborane in the molecular dynamics of the system. Values of fitting parameters, calculated Tg values, and a fragility index are also given for comparison. Reduced localized motion of the soft PBD phase, as well as reinforcement of the hard urethane phases is observed upon the introduction of n

  15. Comparative Inhibition Study of Compounds Identified in the Methanolic Extract of Apamarga Kshara Against Trichomonas vaginalis Carbamate Kinase (TvCK): An Enzoinformatics Approach.

    Science.gov (United States)

    Shaikh, Sibhghatulla; Aaqil, Hamida; Rizvi, Syed Mohd Danish; Shakil, Shazi; Abuzenadah, Adel M; Gupta, Pragya; Saxena, Soumya; Tiwari, Rohit Kr; Kumar, Ajai

    2016-12-01

    In the present study, we have identified ten compounds, namely dodecanol acid, myristic acid, neophytadiene, palmitic acid, heptadecanoic acid, linoleic acid, elaidic acid, 3-7-dimethyl acid, stearic acid and methyl eicos acid, of the methanolic extract of Apamarga Kshara by GC-MS analysis. Apamarga Kshara has been reported to be active against cervical erosion. Major causal organism for cervical erosion is Trichomonas vaginalis. However, there is a paucity of information about the mechanism of action and inhibitory effect of the biologically active natural compounds presented in A. Kshara against this organism (T. vaginalis). Therefore, present investigation was conducted to observe possible interactions of these compounds on T. vaginalis carbamate kinase using molecular docking software 'AutoDock 4.2.' Identification of the amino acid residues crucial for the interaction between T. vaginalis carbamate kinase and these natural compounds is of due scientific interest. The study will aid in efficacious and safe clinical use of the above-mentioned compounds.

  16. Studies of the Atmospheric Chemsitry of Energy-Related Volatile Organic Compounds and of their Atmospheric Reaction Products

    Energy Technology Data Exchange (ETDEWEB)

    Roger Atkinson; Janet Arey

    2007-04-14

    The focus of this contract was to investigate selected aspects of the atmospheric chemistry of volatile organic compounds (VOCs) emitted into the atmosphere from energy-related sources as well as from biogenic sources. The classes of VOCs studied were polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs, the biogenic VOCs isoprene, 2-methyl-3-buten-2-ol and cis-3-hexen-1-ol, alkenes (including alkenes emitted from vegetation) and their oxygenated atmospheric reaction products, and a series of oxygenated carbonyl and hydroxycarbonyl compounds formed as atmospheric reaction products of aromatic hydrocarbons and other VOCs. Large volume reaction chambers were used to investigate the kinetics and/or products of photolysis and of the gas-phase reactions of these organic compounds with hydroxyl (OH) radicals, nitrate (NO3) radicals, and ozone (O3), using an array of analytical instrumentation to analyze the reactants and products (including gas chromatography, in situ Fourier transform infrared spectroscopy, and direct air sampling atmospheric pressure ionization tandem mass spectrometry). The following studies were carried out. The photolysis rates of 1- and 2-nitronaphthalene and of eleven isomeric methylnitronaphthalenes were measured indoors using blacklamp irradiation and outdoors using natural sunlight. Rate constants were measured for the gas-phase reactions of OH radicals, Cl atoms and NO3 radicals with naphthalene, 1- and 2-methylnaphthalene, 1- and 2-ethylnaphthalene and the ten dimethylnaphthalene isomers. Rate constants were measured for the gas-phase reactions of OH radicals with four unsaturated carbonyls and with a series of hydroxyaldehydes formed as atmospheric reaction products of other VOCs, and for the gas-phase reactions of O3 with a series of cycloalkenes. Products of the gas-phase reactions of OH radicals and O3 with a series of biogenically emitted VOCs were identified and quantified. Ambient atmospheric measurements of the concentrations of a

  17. In silico identification of potential drug compound against Peroxisome proliferator-activated receptor-gamma by virtual screening and toxicity studies for the treatment of Diabetic Nephropathy.

    Science.gov (United States)

    Singh, Smrita; Mohanty, Aparajita

    2017-06-08

    Diabetic Nephropathy is a serious complication of diabetes mellitus. Current therapeutic strategies of Diabetic Nephropathy are based on control of modifiable risks like hypertension, glucose levels, and dyslipidemia. Peroxisome proliferator activated receptor-gamma (PPAR-γ) is implicated in several metabolic syndromes including Diabetic Nephropathy, besides obesity, insulin insensitivity, dislipidemia, inflammation, and hypertension. In the present study, virtual screening of 617 compounds from two different public databases was done against PPAR-γ with an objective to find a possible lead compound. Two softwares, PyRx and iGEMDOCK, were used to achieve the docking accuracy in order to avoid loss of candidate compounds. Rosiglitazone (used to treat Diabetic Nephropathy) was taken as the standard compound. A total of 30 compounds with good binding affinity with PPAR-γ were selected for further filtering, on the basis of absorption, distribution, metabolism, excretion, and toxicity (ADMET). The interaction profiling of these 30 compounds, showed a minimum of one and maximum of three interactions with reference to rosiglitazone (SER-289, HIS-449, HIS-323, TYR-473). The fulfilling of ADMET analysis criteria of 30 compounds led to the selection of four compounds (ZINC ID 00181552, 00276456, 00298314, 00448009). Molecular dynamics simulation of these lead compounds in complex with PPAR-γ revealed that three of the four compounds formed a stable complex in the ligand-binding pocket of PPAR-γ during 20-ns simulation. Hence, these three (ZINC ID 00181552, 00276456, 00298314) of the four compounds are potential candidates for experimental validation of biological activity against PPAR-γ in future drug discovery studies.

  18. Study on the applicability of structural and morphological parameters of selected uranium compounds for nuclear forensic purposes

    Energy Technology Data Exchange (ETDEWEB)

    Ho Mer Lin, Doris

    2015-03-13

    Nuclear forensic science or nuclear forensics, is a relatively young discipline which evolved due to the need of analysing interdicted nuclear or radioactive material, necessary for determining its origin. Fundamentally, nuclear forensic science makes use of measurable material properties, referred to as ''signatures'', which provide hints on the history of the material. As part of the advancement in this multi-faceted field, new signatures are constantly sought after and as well as analytical techniques to efficiently and accurately determine the signatures. The work carried out in this study is part of this fulfilment to investigate new structural and morphological parameters as possible new nuclear forensic signatures for selected uranium compounds. The scientific goals have been oriented into three parts for investigations in this study. Firstly, five different compositions of uranium ore concentrates (UOCs) were prepared in the laboratory under well-defined conditions. These materials were subsequently characterized by several techniques such as X-ray diffraction, thermogravimetry/differential thermal analysis, Infrared and Raman spectroscopy, mass spectrometry, scanning electron microscopy etc. Such materials were pivotal for comparison with the industrial samples. Secondly, several uranium compounds, mainly UOCs were measured using Raman spectroscopy. At least three different Raman spectrometers were used and a comparison made in their performance and suitability for nuclear forensics. Raman spectra of industrial uranium materials were interpreted with regard to compound identification and to determination of (anionic) impurities. Anionic impurities that were present were identified and they could provide clues to the processing history of the samples. Statistical techniques such as principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) were applied to several Raman spectra. The analysis showed that

  19. Characterizations of volatile organic compounds (VOCs) from vehicular emissions at roadside environment: The first comprehensive study in Northwestern China

    Science.gov (United States)

    Li, Bowei; Ho, Steven Sai Hang; Xue, Yonggang; Huang, Yu; Wang, Liqin; Cheng, Yan; Dai, Wenting; Zhong, Haobin; Cao, Junji; Lee, Shuncheng

    2017-07-01

    Vehicular emission (VE) is one of the important anthropogenic sources for ground-level volatile organic compounds (VOCs) in both urban and suburban areas. A first comprehensive campaign was conducted at an urban roadside in Xi'an, China in summer, 2016. A total of 57 VOCs, as known as critical surface ozone (O3) precursors, and other trace gases were measured simultaneously during the sampling period. Iso-pentane, a tracer of gasoline evaporation, was the most abundant VOC in the roadside samples, followed by isobutane and benzene, attributed to the largest composition (∼70%) of gasoline-fueled vehicles on the road. The molar ratio of toluene/benzene (T/B) in our study (0.36) is far lower than the range reported in other cities, indicating the stronger contributions from diesel emissions. The results of source apportionment achieved with positive matrix factorization (PMF) receptor model were highly consistent with the vehicles compositions, strongly evidenced that the precise characterization of the VE sources from those marker species. The degrees of individual compound contributed to O3 production were weighed by ozone formation potential (OFP). Propylene (20%), 1-butene (11%) and iso-pentane(10%) were the top three contributors at the roadside. The information of this study complements the VOCs database regarding to the VE sources in Northwestern China.

  20. A comparative study on the potential of epiphytic yeasts isolated from tropical fruits to produce flavoring compounds.

    Science.gov (United States)

    Grondin, Eric; Shum Cheong Sing, Alain; Caro, Yanis; Raherimandimby, Marson; Randrianierenana, Ando Lalaniaina; James, Steve; Nueno-Palop, Carmen; François, Jean Marie; Petit, Thomas

    2015-06-16

    In recent years, there has been an increasing interest in identifying and characterizing the yeast flora associated with diverse types of habitat because of the many potential desirable technological properties of these microorganisms, especially in food applications. In this study, a total of 101 yeast strains were isolated from the skins of tropical fruits collected in several locations in the South West Indian Ocean. Sequence analysis of the D1/D2 domains of the large subunit (LSU) ribosomal RNA gene identified 26 different species. Among them, two species isolated from the skins of Cape gooseberry and cocoa beans appeared to represent putative new yeast species, as their LSU D1/D2 sequence was only 97.1% and 97.4% identical to that of the yeasts Rhodotorula mucilaginosa and Candida pararugosa, respectively. A total of 52 Volatile Organic Compounds (VOCs) were detected by Head Space Solid Phase Micro Extraction coupled to Gas Chromatography and Mass Spectroscopy (HS-SPME-GC/MS) from the 26 yeast species cultivated on a glucose rich medium. Among these VOCs, 6 uncommon compounds were identified, namely ethyl but-2-enoate, ethyl 2-methylbut-2-enoate (ethyl tiglate), ethyl 3-methylbut-2-enoate, 2-methylpropyl 2-methylbut-2-enoate, butyl 2-methylbut-2-enoate and 3-methylbutyl 2-methylbut-2-enoate, making them possible yeast species-specific markers. In addition, statistical methods such as Principal Component Analysis allowed to associate each yeast species with a specific flavor profile. Among them, Saprochaete suaveolens (syn: Geotrichum fragrans) turned to be the best producer of flavor compounds, with a total of 32 out of the 52 identified VOCs in its flavor profile.

  1. Comparative study of aromatic compounds in fruit wines from raspberry, strawberry, and mulberry in central Shaanxi area

    Directory of Open Access Journals (Sweden)

    Yiming Feng

    2015-11-01

    Full Text Available Background: Although grape wines have firmly dominated the production and consumption markets of fruit wines, raspberry, strawberry, and mulberry have been utilized to make wines because of their joyful aroma and high contents of polyphenolic phytochemicals and essential fatty acids. However, little is known about aromatic compounds of the wines produced from these three fruits. Methods: The aromatic composition of fruit wines produced from raspberry, strawberry, mulberry, and red grape was analyzed by GC-MS. Odor activity values (OAVs and relative odor contributions (ROCs were used to estimate the sensory contribution of the aromatic compounds to the overall flavor of the wines. Results: In strawberry, raspberry, and mulberry wines, 27, 30, and 31 odorants were detected, respectively. Alcohols formed the most abundant group, followed by esters and acids. The grape wine contained a wider variety (16 types of alcohols, and 4-methyl-2-pentanol and 2,3-butanediol were not present in the three fruit wines. The quantity of esters in raspberry (1.54% and mulberry wines (2.08% were higher than those of strawberry wine (0.78%, and mulberry wine contained more types of esters. There were no significant differences of acids between the three fruit wines and the control wine. In addition, 2-heptanone, 2-octanone, 2-nonanone, and 2-undecanone were unique to raspberry wine, and nonanal was present only in mulberry wine. The indistinguishable aroma of the three fruit wines was attributed to the dominance of fruity and floral odor components derived from ethyl esters of fatty acids and their contributions to the global aroma of the three fruit wines. Conclusion: The present study demonstrated that there were significant differences in the volatile components of fruit wines made from raspberry, strawberry, and mulberry. The aroma compounds were more abundant in the raspberry and mulberry wines than in the strawberry wine, but the quality of strawberry wine was

  2. Efficacy of skin wash on dermal absorption: an in vitro study on four model compounds of varying solubility

    DEFF Research Database (Denmark)

    Nielsen, Jesper Bo

    2010-01-01

    that percutaneous penetration continues after end of exposure due to the reservoir present in the skin. However, penetration rate will decrease significantly, and it is evident that simple hand-wash after end of exposure not only reduces the amount of residue present in the upper skin compartment but also......PURPOSE: Following dermal exposure to chemicals causing systemic toxicity, the general advice to avoid further systemic exposure is to wash the skin. The present study uses four model compounds (benzoic acid, glyphosat, caffeine, malathion) with varying size and solubility to substantiate...... this advice and quantify the effect of skin wash following 6 h dermal exposure on subsequent extent of skin penetration and deposition within the skin compartment. METHOD: Percutaneous penetration through human skin is studied in an in vitro model with static diffusion cells. RESULTS: The study demonstrates...

  3. Applicability of Generic Assays Based on Liquid Chromatography-Electrospray Mass Spectrometry to Study in vitro Metabolism of 55 Structurally Diverse Compounds.

    Science.gov (United States)

    Rousu, Timo; Hokkanen, Juho; Pelkonen, Olavi R; Tolonen, Ari

    2010-01-01

    Liquid chromatography-mass spectrometry (LC-MS) with generic gradient elution for a large number of chemically different compounds is a common approach in drug development, used to acquire a large amount of data in a short time frame for drug candidates. The analysis with non-optimized parameters however may lead to a poor method performance for many compounds, and contains a risk of losing important information. Here, generic electrospray time of flight (ESI-TOF) MS methods in various pH conditions were tested for 55 chemically diverse compounds (10 acids, 25 bases, 17 neutrals, and 3 amphoterics), aiming to find best analytical conditions for each compound, for studies of in vitro metabolic properties in liver preparations. The effect of eluent pH and elution gradient strength on chromatographic performance and electrospray MS ionization efficiency were examined for each compound. The data are evaluated how well the best generic approach could cover the analysis of test compounds and how many compounds would still need completely different analytical conditions after that. Aqueous mobile phase consisting of 0.05% acetic acid and 5 mM ammonium acetate (pH 4.4) showed the best general suitability for the analyses, showing adequate performance for metabolite profiling for 41 out of 55 compounds either in positive or negative ion mode. In positive ion mode, the main limitation of performance in various pH conditions was generally not the lack of ionization, but rather the poor chromatographic performance (inadequate retention or poor peak shape), suggesting that more emphasis should be put in finding conditions providing best chromatographic performance, rather than highest ionization properties. However, a single generic approach for a large number of different compounds is not likely to produce good results for all compounds. Preferably, at least two or three different conditions are needed for the coverage of a larger number of structurally diverse compounds.

  4. Applicability of generic assays based on liquid chromatography–electrospray mass spectrometry to study in vitro metabolism of 55 structurally diverse compounds

    Directory of Open Access Journals (Sweden)

    Timo Rousu

    2010-08-01

    Full Text Available Liquid chromatography-mass spectrometry (LC/MS with generic gradient elution for a large number of chemically different compounds is a common approach in drug development, used to acquire a large amount of data in a short time frame for drug candidates. The analysis with non-optimised parameters however may lead to a poor method performance for many compounds, and contains a risk of losing important information. Here, generic electrospray-time-of-flight (ESI-TOF MS methods in various pH conditions were tested for 55 chemically diverse compounds (10 acids, 25 bases, 17 neutrals and 3 amphoterics, aiming to find best analytical conditions for each compound, for studies of in vitro metabolic properties in liver preparations. The effect of eluent pH and elution gradient strength on chromatographic performance and electrospray MS ionisation efficiency were examined for each compound. The data are evaluated how well the best generic approach could cover the analysis of test compounds and how many compounds would still need completely different analytical conditions after that. Aqueous mobile phase consisting of 0.05% acetic acid and 5 mM ammonium acetate (pH 4.4 showed the best general suitability for the analyses, showing adequate performance for metabolite profiling for 41 out of 55 compounds either in positive or negative ion mode. In positive ion mode, the main limitation of performance in various pH conditions was generally not the lack of ionisation, but rather the poor chromatographic performance (inadequate retention or poor peak shape, suggesting that more emphasis should be put in finding conditions providing best chromatographic performance, rather than highest ionisation properties. However, a single generic approach for a large number of different compounds is not likely to produce good results for all compounds. Preferably, at least two or three different conditions are needed for the coverage of a larger number of structurally diverse

  5. Structural, magnetic and electronic transport studies of RAgSn2 compounds (R = Y, Tb, Dy, Ho and Er) with Cu3Au-type

    Indian Academy of Sciences (India)

    L Romaka; V V Romaka; I Lototska; A Szytula; B Kuzhel; A Zarzycki; E K Hlil; D Fruchart

    2013-12-01

    RAgSn2 compounds, where R = Y, Tb, Dy, Ho and Er, were synthesized by arc-melting and subsequent annealing at 870 K. The formation of cubic phases with Cu3Au-type structure (space group $\\bar{3}$) was studied. Magnetic property measurements showed that in paramagnetic state, the compounds with magnetic rareearth atoms are Curie–Weiss paramagnets and order antiferromagnetically at low temperatures. YAgSn2 is a Pauli paramagnet in 100–300 K temperature range. The electrical properties of RAgSn2 compounds were investigated by means of electrical resistivity and Seebeck coefficient measurements in 4.2–300 K temperature range. All investigated compounds exhibit metallic type of conductivity. Electronic structure calculations based on full potential linearized augmented plane wave (FLAPW)method is also carried out to probe themagnetic and electronic structures of RAgSn2 compounds. Comparisons between experimental data and calculations are discussed.

  6. Applications of Solid-Phase Microextraction and Gas Chromatography/Mass Spectrometry (SPME-GC/MS in the Study of Grape and Wine Volatile Compounds

    Directory of Open Access Journals (Sweden)

    Annarita Panighel

    2014-12-01

    Full Text Available Volatile compounds are responsible for the wine “bouquet”, which is perceived by sniffing the headspace of a glass, and of the aroma component (palate-aroma of the overall flavor, which is perceived on drinking. Grape aroma compounds are transferred to the wine and undergo minimal alteration during fermentation (e.g., monoterpenes and methoxypyrazines; others are precursors of aroma compounds which form in winemaking and during wine aging (e.g., glycosidically-bound volatile compounds and C13-norisoprenoids. Headspace solid phase microextraction (HS-SPME is a fast and simple technique which was developed for analysis of volatile compounds. This review describes some SPME methods coupled with gas chromatography/mass spectrometry (GC/MS used to study the grape and wine volatiles.

  7. A neutron diffraction study of the R{sub 15}Ge{sub 9}C compounds (R = Ce, Pr, Nd)

    Energy Technology Data Exchange (ETDEWEB)

    Tencé, S., E-mail: tence@icmcb-bordeaux.cnrs.fr [Université Grenoble Alpes, Institut Néel, BP166, F-38042 Grenoble (France); CNRS, Institut Néel, Rue des Martyrs, F-38042 Grenoble (France); Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux, 87 Avenue Docteur Albert Schweitzer, 33608 Pessac Cedex (France); Isnard, O. [Université Grenoble Alpes, Institut Néel, BP166, F-38042 Grenoble (France); CNRS, Institut Néel, Rue des Martyrs, F-38042 Grenoble (France); Wrubl, F. [Department of Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genoa (Italy); Manfrinetti, P. [Department of Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genoa (Italy); Institute SPIN – CNR, Corso Perrone 24, 16152 Genoa (Italy)

    2014-05-01

    Highlights: • Neutron diffraction study was performed on the germanides R{sub 15}Ge{sub 9}C (R = Ce, Pr, Nd). • The interstitial carbon atoms occupy mainly the site 2b in (1/3 2/3 ∼1/2). • The three compounds display canted ferromagnetic structures with k = [0 0 0]. • Carbon insertion strongly modifies the magnetic properties of the parent germanides. - Abstract: In this work we report the results of the neutron diffraction investigation performed on the germanides R{sub 15}Ge{sub 9}C, for R = Ce, Pr and Nd (La{sub 15}Ge{sub 9}Fe-type, hP50, P6{sub 3}mc, Z = 2), to refine the crystal superstructure of these compounds and determine their magnetic structures. The interstitial carbon atoms occupy mainly the 2b Wyckoff site in the position (1/3 2/3 ∼1/2) and also, with a smaller occupancy rate, the Wyckoff site 2a at (0 0 ∼1/2). In the magnetic state, the three compounds display predominantly a ferromagnetic behavior with the propagation vector k = [0 0 0]. These results are in agreement with the magnetization measurements, with T{sub C} = 10, 30 and 80 K as Curie temperature of Ce{sub 15}Ge{sub 9}C, Pr{sub 15}Ge{sub 9}C and Nd{sub 15}Ge{sub 9}C, respectively. Ce{sub 15}Ge{sub 9}C and Nd{sub 15}Ge{sub 9}C present a ferromagnetic alignment of the R moments along the c-axis and an antiferromagnetic spin arrangement within the (a–b) plane. For Pr{sub 15}Ge{sub 9}C the ferromagnetic contribution is found within the (a–b) plane, as previously observed for the isotypic compound Tb{sub 15}Si{sub 9}C. The carbides crystal structure possesses four inequivalent rare earth sites carrying different magnetic moments, leading to mean values of 0.9 μ{sub B}/Ce, 1.1 μ{sub B}/Pr and 2.2 μ{sub B}/Nd for Ce{sub 15}Ge{sub 9}C, Pr{sub 15}Ge{sub 9}C and Nd{sub 15}Ge{sub 9}C, respectively. The magnetic structures of these R{sub 15}Ge{sub 9}C compounds differ strongly from those of their parent R{sub 5}Ge{sub 3} germanides, but present strong similarities with the

  8. Application of passive dosing to study the biotransformation and biodegradation of hydrophobic compounds

    DEFF Research Database (Denmark)

    Smith, E. C.; Rein, Arno; Trapp, Stefan

    2011-01-01

    is significant even at low dissolved concentrations thus facilitating measurement of the relevant endpoint (e.g., metabolic products in biotransformation or growth in biodegradation). This study details two applications of passive dosing for studying bio-transformation/degradation. A format has been developed...... to study the biodegradation of phenanthrene and fluoranthene by the bacterial strain EPA 505, allowing degradation rates to be quantified at defined freely dissolved concentrations from mg/L down to ng/L levels. Passive dosing was also applied for quantifying the mutagenicity of benzo(a)pyrene metabolites...

  9. Comparative theoretical study of the UV/Vis absorption spectra of styrylpyridine compounds using TD-DFT calculations.

    Science.gov (United States)

    Castro, Maria Eugenia; Percino, M Judith; Chapela, Victor M; Soriano-Moro, Guillermo; Ceron, Margarita; Melendez, Francisco J

    2013-05-01

    This study examined absorption properties of 2-styrylpyridine, trans-2-(m-cyanostyryl)pyridine, trans-2-[3-methyl-(m-cyanostyryl)]pyridine, and trans-4-(m-cyanostyryl)pyridine compounds based on theoretical UV/Vis spectra, with comparisons between time-dependent density functional theory (TD-DFT) using B3LYP, PBE0, and LC-ωPBE functionals. Basis sets 6-31G(d), 6-31G(d,p), 6-31+G(d,p), and 6-311+G(d,p) were tested to compare molecular orbital energy values, gap energies, and maxima absorption wavelengths. UV/Vis spectra were calculated from fully optimized geometry in B3LYP/6-311+G(d,p) in gas phase and using the IEFPCM model. B3LYP/6-311+G(d,p) provided the most stable form, a planar structure with parameters close to 2-styrylpyridine X-ray data. Isomeric structures were evaluated by full geometry optimization using the same theory level. Similar energetic values were found: ~4.5 kJ mol(-1) for 2-styrylpyridine and ~1 kJ mol(-1) for derivative compound isomers. The 2-styrylpyridine isomeric structure differed at the pyridine group N-atom position; structures considered for the other compounds had the cyano group attached to the phenyl ring m-position equivalent. The energy difference was almost negligible between m-cyano-substituted molecules, but high energy barriers existed for cyano-substituted phenyl ring torsion. TD-DFT appeared to be robust and accurate approach. The B3LYP functional with the 6-31G(d) basis set produced the most reliable λmax values, with mean errors of 0.5 and 12 nm respect to experimental values, in gas and solution, respectively. The present data describes effects on the λmax changes in the UV/Vis absorption spectra of the electron acceptor cyano substituent on the phenyl ring, the electron donor methyl substituent, and the N-atom position on the electron acceptor pyridine ring, causing slight changes respect to the 2-styrylpyridine title compound.

  10. Multipurpose Compound

    Science.gov (United States)

    1983-01-01

    Specially formulated derivatives of an unusual basic compound known as Alcide may be the answer to effective treatment and prevention of the disease bovine mastitis, a bacterial inflammation of a cow's mammary gland that results in loss of milk production and in extreme cases, death. Manufactured by Alcide Corporation the Alcide compound has killed all tested bacteria, virus and fungi, shortly after contact, with minimal toxic effects on humans or animals. Alcide Corporation credits the existence of the mastitis treatment/prevention products to assistance provided the company by NERAC, Inc.

  11. Comparison of volatile organic compounds from lung cancer patients and healthy controls-challenges and limitations of an observational study.

    Science.gov (United States)

    Schallschmidt, Kristin; Becker, Roland; Jung, Christian; Bremser, Wolfram; Walles, Thorsten; Neudecker, Jens; Leschber, Gunda; Frese, Steffen; Nehls, Irene

    2016-10-12

    This paper outlines the design and performance of an observational study on the profiles of volatile organic compounds (VOCs) in the breath of 37 lung cancer patients and 23 healthy controls of similar age. The need to quantify each VOC considered as a potential disease marker on the basis of individual calibration is elaborated, and the quality control measures required to maintain reproducibility in breath sampling and subsequent instrumental trace VOC analysis using solid phase microextraction-gas chromatography-mass spectrometry over a study period of 14 months are described. Twenty-four VOCs were quantified on the basis of their previously suggested potential as cancer markers. The concentration of aromatic compounds in the breath was increased, as expected, in smokers, while lung cancer patients displayed significantly increased levels of oxygenated VOCs such as aldehydes, 2-butanone and 1-butanol. Although sets of selected oxygenated VOCs displayed sensitivities and specificities between 80% and 90% using linear discriminant analysis (LDA) with leave-one-out cross validation, the effective selectivity of the breath VOC approach with regard to cancer detection is clearly limited. Results are discussed against the background of the literature on volatile cancer marker investigations and the prospects of linking increased VOC levels in patients' breath with approaches that employ sniffer dogs. Experience from this study and the literature suggests that the currently available methodology is not able to use breath VOCs to reliably discriminate between cancer patients and healthy controls. Observational studies often tend to note significant differences in levels of certain oxygenated VOCs, but without the resolution required for practical application. Any step towards the exploitation of differences in VOC profiles for illness detection would have to solve current restrictions set by the low and variable VOC concentrations. Further challenges are the technical

  12. Boron Neutron Capture Therapy (BCNT) for the Treatment of Liver Metastases: Biodistribution Studies of Boron Compounds in an Experimental Model

    Energy Technology Data Exchange (ETDEWEB)

    Marcela A. Garabalino; Andrea Monti Hughes; Ana J. Molinari; Elisa M. Heber; Emiliano C. C. Pozzi; Maria E. Itoiz; Veronica A. Trivillin; Amanda E. Schwint; Jorge E. Cardoso; Lucas L. Colombo; Susana Nievas; David W. Nigg; Romina F. Aromando

    2011-03-01

    Abstract We previously demonstrated the therapeutic efficacy of different boron neutron capture therapy (BNCT) protocols in an experimental model of oral cancer. BNCT is based on the selective accumulation of 10B carriers in a tumor followed by neutron irradiation. Within the context of exploring the potential therapeutic efficacy of BNCT for the treatment of liver metastases, the aim of the present study was to perform boron biodistribution studies in an experimental model of liver metastases in rats. Different boron compounds and administration conditions were assayed to determine which administration protocols would potentially be therapeutically useful in in vivo BNCT studies at the RA-3 nuclear reactor. A total of 70 BDIX rats were inoculated in the liver with syngeneic colon cancer cells DHD/K12/TRb to induce the development of subcapsular tumor nodules. Fourteen days post-inoculation, the animals were used for biodistribution studies. We evaluated a total of 11 administration protocols for the boron compounds boronophenylalanine (BPA) and GB-10 (Na210B10H10), alone or combined at different dose levels and employing different administration routes. Tumor, normal tissue, and blood samples were processed for boron measurement by atomic emission spectroscopy. Six protocols proved potentially useful for BNCT studies in terms of absolute boron concentration in tumor and preferential uptake of boron by tumor tissue. Boron concentration values in tumor and normal tissues in the liver metastases model show it would be feasible to reach therapeutic BNCT doses in tumor without exceeding radiotolerance in normal tissue at the thermal neutron facility at RA-3.

  13. Effectiveness of Rice Husk Ash in Removal of Phenolic Compounds from Aqueous Solutions, Equilibrium and Kinetics Studies

    Directory of Open Access Journals (Sweden)

    Majid Kermani

    2012-04-01

    Full Text Available Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives: Phenols in trace quantities are usually present in the treated effluent of many wastewater-treatment plants. Phenol compounds even at low concentration can cause toxicity, health and significant taste and odor problem in drinking waters. This research focuses on understanding the sorption process and developing a cost-effective technology for the treatment of water contaminated with phenolic compounds, which are discharged into the aquatic environment from a variety of sources. In order to remove phenolic compounds from water, a new natural sorbent, rice husk ash, was developed.Materials and Methods: Removal of phenol, 2-chlorophenol and 4-chlorophenol were characterized by spectrophotometric technique at wavelengths of 269.5, 274 and 280 nm, respectively, under batch equilibrium conditions and via changing the parameters of contact time, initial pH, and initial concentration of adsorbates and dosages of sorbent. Finally, the results were analyzed by the kinetic and isotherm models.Results: in this study, the equilibrium time was found to be 240 min for full equilibration of adsorbates. Removal percent of 2-chlorophenol was lower than two others. The maximum removal of phenol, 2-CP and 4-CP was observed at an initial pH of 5. The percentage removal of these phenolic compounds increased with increasing adsorbent dose and decreasing initial concentration. In kinetics studies, correlation coefficient and ARE factor showed that the sorption of phenol (R2=0.9999, 2-chlorophenol (R2=0.9992 and 4-chlorophenol (R2=1 fitted by pseudo second order model. Isotherm studies also revealed that, Langmuirmodel for phenol (R2=0.9499, Freundlich model for 2-chlorophenol (R2=0.9659 and 4-chlorophenol (R2=0.9542 were the best choices to describe the sorption behaviors.Conclusion: Sorption process is highly dependent on the pH and it affects adsorbent surface

  14. Taxonomic study and partial characterization of antimicrobial compounds from a moderately halophilic strain of the genus Actinoalloteichus

    Directory of Open Access Journals (Sweden)

    Farida Boudjelal

    2011-09-01

    Full Text Available A moderately halophilic actinomycete strain designated AH97 was isolated from a saline Saharan soil, and selected for its antimicrobial activities against bacteria and fungi. The AH97 strain was identified by morphological, chemotaxonomic and phylogenetic analyses to the genus Actinoalloteichus. Analysis of the 16S rDNA sequence of strain AH97 showed a similarity level ranging between 95.8% and 98.4% within Actinoalloteichus species, with A. hymeniacidonis the most closely related. The comparison of the physiological characteristics of AH97 with those of known species of Actinoalloteichus showed significant differences. Strain AH97 showed an antibacterial and antifungal activity against broad spectrum of microorganisms known to be human and plant pathogens. The bioactive compounds were extracted from the filtrate culture with n-butanol and purified using thin layer chromatography and high pressure liquid chromatography procedures. Two active products were isolated, one hydrophilic fraction (F1 and another hydrophobic (F2. Ultraviolet-visible, infrared, mass and ¹H and 13C nuclear magnetic resonance spectroscopy studies suggested that these molecules were the dioctyl phthalate (F2 and an aminoglycosidic compound (F1.

  15. Studies of n-Octanol/water Partition Coefficients (IgKow) for Organophosphate Compounds by Density Functional Theory

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-Xia; WANG Zun-Yao; ZHAI Zhi-Cai; LIU Hong-Yan; WANG Lian-Sheng

    2007-01-01

    Optimized calculation of 35 dialkyl phenyl phosphate compounds (OPs) was carried out at the B3LYP/6-31G* level in Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained parameters were taken as theoretical descriptors to establish the novel QSPR model for predicting n-octanol/water partition coefficients (IgKow) of OPs. The new model achieved in this work contains three variables, i.e., molecular volume (Vm),dipole moment of the molecules (μ) and enthalpy (H0). For this model, R2 = 0.9167 and SD = 0.31 at large t values. In addition, the variation inflation factors (VIF) of variables are all close to 1.0,suggesting high accuracy of the predicting model. And the results of cross-validation test (q2 =0.8993) and method validation also showed the model of this study exhibited optimum stability and better predictive power than that from semi-empirical method. The model achieved can be used to predict lgKow of congeneric compounds.

  16. Study on Peroxide Curing System of HNBR Compound%HNBR过氧化物硫化体系的研究

    Institute of Scientific and Technical Information of China (English)

    陈琪; 王文艳; 张振秀; 辛振祥

    2012-01-01

    In this paper, the effects of curing coagents TAIC, PDM and S on the curing characteristics and mechanical properties of HNBR compound were studied. The results showed that the HN-BR compound cured by PDM had the shortest scorch time and optimum curing time, and the crosslink efficiency was high, and the mechanical properties were best. The thermal aging properties were improved when PDM contents increased from 1. 5 phr to 3 phr. When DCP content was 10 phr, the crosslink degree of HNBR blend increased with the increase of PDM content, and the optimum curing time decreased.%研究了硫化促进剂异氰尿酸三烯丙酯(TAIC)、N,N' -间苯撑马来酰亚胺(PDM)和硫黄(S)对氢化丁腈橡胶(HNBR)硫化特性和力学性能的影响.结果表明,含PDM的胶料t10和t90均最短,交联效率较高,力学性能最好;PDM用量为1.5份到3份时能有效提高HNBR胶料的耐热氧老化性能.DCP用量为10份时,增加PDM用量可有效提高HNBR的交联程度,缩短交联时间.

  17. Study of phenolic compound and antioxidant activity of date fruit as a function of ripening stages and drying process.

    Science.gov (United States)

    Shahdadi, F; Mirzaei, H O; Daraei Garmakhany, A

    2015-03-01

    Edible parts of two varieties of date palm (Mazfati and Kalute varieties) (Phoenix dactylifera) fruits (DPF) from Iran were analyzed to determine their phenolic compound and antioxidant activities (AA). Antioxidant activity evaluated using typical methods such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH), reducing power and total antioxidant method. The total phenolic content (TPC) of the DPF was measured using Folin-Ciocalteau method. The samples used in this study included samples were gathered at three stages of khalaal, rutab, tamr and dried date from Bam and Jiroft date. The TPC ranged from 2.89 to 4.82, 1074 to 856.4 and 782.8 mg gallic acid equivalents (GAE/100 gdw sample) for khalal, rutab and tamr stage of Mozafati variety, respectively. This work demonstrates the potential of Iranian dates as good sources of antioxidant which can be used as functional food ingredients. The influence of sun drying process and oven drying at temperature ranged 50-80 °C on phenolic compounds and AA of date palm fruits were investigated. Result of drying process showed that TPC and AA varied with temperature and decreased by increase of drying temperature (from 667.3 to 610.5 mg galic acid in sun dried dates of Mozafati and Kaluteh respectively to 314.2 and 210.4 in dried dates (80 °C) of Mozafati and Kaluteh respectively).

  18. The use of anthracene as a model compound in a comparative study of hydrous pyrolysis methods for industrial waste remediation.

    Science.gov (United States)

    Nkansah, Marian Asantewah; Christy, Alfred A; Barth, Tanja

    2011-07-01

    Polycyclic aromatic hydrocarbons are very stable compounds and tend to bioaccumulate in the environment due to their high degree of conjugation and aromaticity. Hydrous pyrolysis is explored as a technique for the treatment of industrial water containing PAH, using anthracene as a model compound. The reactivity of anthracene under a range of temperatures and durations are studied in this paper. Aliquots of 1.0-10.0mg of anthracene in a range of 1.0-5.0 mL of H(2)O are subjected to hydrous pyrolysis under varied conditions of temperature, reagents and duration. The conditions include oxidising systems comprising distilled water, hydrogen peroxide and Nafion-SiO(2) solid catalyst in water; and reducing systems of formic acid and formic acid/Nafion-SiO(2)/Pd-C catalysts to assess a range of redox reaction conditions. Oxygen in air played a role in some of the reaction conditions. Pyrolysed products were identified and quantified by the use of Gas Chromatography-Mass Spectrometry (GC-MS). The major products were anthrone, anthraquinone, xanthone from oxidation; and multiple hydro-anthracene derivatives from reductive hydogenation. The nature of reaction conditions influenced the extent of anthracene degradation. The products formed are more reactive (less stable) as compared to anthracene the starting material and will therefore be less persistent in the environment.

  19. Multiscale Study of Interfacial Intermetallic Compounds in a Dissimilar Al 6082-T6/Cu Friction-Stir Weld

    Science.gov (United States)

    Avettand-Fenoël, M. N.; Taillard, R.; Ji, G.; Goran, D.

    2012-12-01

    The objective of this work was to characterize the Al x Cu y intermetallic compounds (IMCs) formed at the abutting interface during solid-state friction-stir welding (FSW) of 6082 aluminum alloy and pure copper. As IMCs are potential sources of flaws in case of mechanical loading of welds, their study is essential at various scale lengths. In the present case, they have been identified by neutron diffraction, electron backscattered diffraction, and transmission electron microscopy. Neutron diffraction analyses have shown that a shift of the tool from the interface, in particular towards the Cu part, generates an increase of the IMCs' volume fraction. In accordance with an exacerbation of its kinetics of formation by FSW, a 4- μm-thick layer has precipitated at the interface despite the shortness of the thermal cycle. This layer is composed of two sublayers with the Al4Cu9 and Al2Cu stoichiometry, respectively. Convergent beam electron diffraction analyses have, however, disclosed that the crystallography of the current Al2Cu compound does not comply with the usual tetragonal symmetry of this phase. The Al2Cu phase formation results from both the local chemical composition and thermodynamics, whereas the development of Al4Cu9 is rather due to both the local chemical composition and the shortness of the local FSW thermal cycle.

  20. Simultaneous determination of bioactive compounds in Piper nigrum L. and a species comparison study using HPLC-PDA.

    Science.gov (United States)

    Rao, Vidadala Rama Subba; Raju, Sagi Satyanarayana; Sarma, Vanka Umamaheswara; Sabine, Fouriner; Babu, Kothapalli Hari; Babu, Katragadda Suresh; Rao, Janaswamy Madhusudana

    2011-08-01

    Piper nigrum L. is a traditional medicine widely used in India for illnesses such as constipation, diarrhoea, earache, gangrene, heart disease, hernia, hoarseness, indigestion, insect bites, insomnia, joint pain, liver problems, lung disease, oral abscesses, sunburn, tooth decay and toothaches. In this study, six bioactive compounds, namely piperine (1), pellitorine (2), guineensine (3), pipnoohine (4), trichostachine (5) and piperonal (6) were quantified in different extracts of P. nigrum L. and compared with those of P. longum L. and P. chaba Hunter. To evaluate the quality of P. nigrum, a simple, accurate and precise HPLC-PDA method was developed for the simultaneous determination of the above-mentioned six compounds. The separation was achieved by Phenomenex Luna RP C(18) column (150 × 4.6 mm, 5 µm, Phenomenex Inc, CA, USA) with a binary gradient solvent system of water-acetonitrile, at a flow rate of 1.0 mL min(-1) and detected at 210, 232, 262 and 343 nm. All six calibration curves showed good linearity (R (2) > 0.9966). The method was reproducible with intra- and inter-day variations of less than 2% and 5%, respectively. The results demonstrated that this method is simple, reliable and suitable for the quality control of these plants.

  1. Study on Technology of Compound Juice of Raspberry%树莓复合果汁的研制

    Institute of Scientific and Technical Information of China (English)

    张志军; 魏雪生; 李淑芳

    2011-01-01

    A compound beverage using raspberry as main material was studied by orthogonal tests and the optimal formula of the beverage was determined as raspberry juice 80 mL, hawthorn juice 10 mL, wolfberry juice 10 mL,chrysanthemum paste 0.1 g, honeysuckle paste 0.1 g, chinese rose 0.3 g, granulated sugar 10 g, honey 3 g, xylooligosaccharides 1.5 g. The results indicated the compounded functional raspberry beverage had delicious flavour of acid and sweet, bright colour, particular flavour, uniform microstructure, lower heat and rich nutrition.%以树莓为主要原料,研制一种树莓复合饮料,通过正交试验确定最佳的饮料配方为:树莓汁80 mL、山楂汁10 mL、枸杞汁10 mL;菊花膏0.1 g、金银花膏0.1 g、月季花膏0.3 g;砂糖10 g、蜂蜜3 g、低聚木糖1.5 g,所制果汁饮料酸甜适口,色泽鲜艳、风味独特、组织状态均匀,且热量低、营养丰富.

  2. A study on transformation of some transition metal oxides in molten steelmaking slag to magnetically susceptible compounds

    Directory of Open Access Journals (Sweden)

    Shatokha V.

    2013-01-01

    Full Text Available Sustainable development of steelmaking requires solving a number of environmental problems. Economically feasible and environmentally friendly recycling of slag wastes is of special concern. Research of the team representing National Metallurgical Academy of Ukraine, Royal Institute of Technology, Carnegie Mellon University and URS Corp revealed a possibility of the controlled phase transformations in the liquid silicate melts followed by formation of the magnetically susceptible compounds. This approach enables selective recovery of metal values from slag. In this paper, the results obtained and further research directions are discussed. A possibility to exploit physical properties of the transition metals, typical for the metallurgical slags (such as Fe, Mn, V and others, and corresponding specific properties of their compounds, such as non-stoichiometry, mixed valency, pseudomorphosis, thermodynamic stability etc, in production of value-added materials from slag wastes is discussed. The results of the studies of thermodynamics and kinetics of oxidation in slags followed by phase transformation with binary, ternary and complex oxides under various physicochemical conditions are discussed in the view of their application for production of the materials with predefined physical properties. Peculiarities of precipitation in slags with various basicities are analysed and demonstrate capacity of the proposed approach in the production of the material with a given structure and size - for example, nano-sized crystals with structure of spinel. The approaches towards industrial realization of the developed method are also discussed.

  3. Studies on allergic reactions after exposure to platinum compounds; Untersuchungen ueber allergische Reaktionen bei Exposition gegen Platinverbindungen (VPT 07A)

    Energy Technology Data Exchange (ETDEWEB)

    Merget, R.; Schultze-Werninghaus, G. [Berufsgenossenschaftliche Kliniken, Bergmannsheil - Universitaetsklinik, Medizinische Klinik und Poliklinik, Abt. fuer Pneumologie, Allergologie und Schlafmedizin, Bochum (Germany)

    1997-12-31

    The aim of the present study was to assess the allergic hazard potential of Pt-containing substances emitted from automotive catalytic converters for the population. This was done by determining exposure-effect relationships in subjects occupationally exposed to platinum compounds in a catalytic converter manufacturing company. The company had been deemed suitable because it could be assumed that the extensive technical industrial safety measures implemented there would make for a considerably reduced exposure to platinum compounds compared to, for example, a platinum separating plant. Exposure-effect relationships were determined on the basis of platinum measurements in a catalytic-converter-manufacturing plant and of a record of new sickness cases. [Deutsch] Ziel der Untersuchung war eine Risikoabschaetzung des Allergie-Gefaehrdungspotentials Pt-haltiger Automobilkatalysatoremittate fuer die Bevoelkerung durch Ermittlung der Expositions-Wirkungsbeziehung bei beruflich gegenueber Platinverbindungen Exponierten in einem Katalysatorfertigungsbertrieb. Der gewaehlte Katalysatorbetrieb war deshalb als geeignet betrachtet worden, weil durch weitgehende technische Arbeitsschutzmassnahmen eine wesentlich geringere Exposition gegenueber Platinverbindungen anzunehmen war als zum Beispiel in Platinscheidereien. Die Expositions-Wirkungsbeziehung sollte durch Platinmessungen in einem Katalysator-Betrieb und Erfassung der Haeufigkeit von Neuerkrankungen im Laengsschnitt definiert werden. (orig.)

  4. Numerical model to quantify biogenic volatile organic compound emissions: The Pearl River Delta region as a case study.

    Science.gov (United States)

    Wang, Xuemei; Situ, Shuping; Chen, Weihua; Zheng, Junyu; Guenther, Alex; Fan, Qi; Chang, Ming

    2016-08-01

    This article compiles the actual knowledge of the biogenic volatile organic compound (BVOC) emissions estimated using model methods in the Pearl River Delta (PRD) region, one of the most developed regions in China. The developed history of BVOC emission models is presented briefly and three typical emission models are introduced and compared. The results from local studies related to BVOC emissions have been summarized. Based on this analysis, it is recommended that local researchers conduct BVOC emission studies systematically, from the assessment of model inputs, to compiling regional emission inventories to quantifying the uncertainties and evaluating the model results. Beyond that, more basic researches should be conducted in the future to close the gaps in knowledge on BVOC emission mechanisms, to develop the emission models and to refine the inventory results. This paper can provide a perspective on these aspects in the broad field of research associated with BVOC emissions in the PRD region.

  5. Caenorhabditis elegans as a model for the screening of anthelminthic compounds: ultrastructural study of the effects of albendazole.

    Science.gov (United States)

    Sant'anna, Viviane; Vommaro, Rossiane C; de Souza, Wanderley

    2013-09-01

    This study investigated the effects of albendazole on the viability, morphology and ultrastructure of different life stages of Caenorhabditis elegans. The albendazole EC50 value after seven days of treatment was 18.43 μM. This concentration was very efficient against all the stages. Light and electron microscopy analysis showed damage to the body wall of the adults and larvae. An intense desquamation of the cuticle of larvae and of the surface of the eggs was observed, preventing their hatching and development. The main ultrastructural damage detected was the degeneration of the mitochondria in the noncontractile muscle of the body wall, which appeared as large vacuoles. This study reaffirmed the use of C. elegans as a screening system for compounds with potential anthelmintic activity and showed the effects of albendazole on the different life stages of these worms.

  6. Preparation of solid-state samples of a transition metal coordination compound for synchrotron radiation photoemission studies

    CERN Document Server

    Crotti, C; Celestino, T; Fontana, S

    2003-01-01

    The aim of this research was to identify a sample preparation method suitable for the study of transition metal complexes by photoemission spectroscopy with synchrotron radiation as the X-ray source, even in the case where the compound is not evaporable. Solid-phase samples of W(CO) sub 4 (dppe) [dppe=1,2-bis(diphenylphosphino)ethane] were prepared according to different methods and their synchrotron radiation XPS spectra measured. The spectra acquired from samples prepared by spin coating show core level peaks only slightly broader than the spectrum recorded from UHV evaporated samples. Moreover, for these samples the reproducibility of the binding energy values is excellent. The dependence of the spin coating technique on parameters such as solvent and solution concentration, spinning speed and support material was studied. The same preparation method also allowed the acquisition of valence band spectra, the main peaks of which were clearly resolved. The results suggest that use of the spin coating techniqu...

  7. A model compound study: the ecotoxicological evaluation of five organic contaminants employing a battery of marine bioassays.

    Science.gov (United States)

    Macken, Ailbhe; Giltrap, Michelle; Foley, Barry; McGovern, Evin; McHugh, Brendan; Davoren, Maria

    2008-06-01

    This paper describes the ecotoxicological evaluation of five organic contaminants frequently detected in marine sediments (tributyltin, triphenyltin, benzo[a]pyrene, fluoranthene, and PCB 153) using three marine species (Vibrio fischeri, Tetraselmis suecica, and Tisbe battagliai). The sensitivity of each species varied for all compounds. The triorganotins were consistently the most toxic to all species. The applicability of each test system to assess the acute toxicity of environmental contaminants and their use in Toxicity Identification Evaluation (TIE) is discussed. Suitability of the Microtox and T. battagliai tests for employment in TIE studies were further assessed through spiking experiments with tributyltin. Results demonstrated that the most effective treatment to remove organotin toxicity from the sample was the C18 resin. The results of this study have important implications for risk assessment in estuarine and coastal waters in Ireland, where, at present the monitoring of sediment and water quality is predominantly reliant on chemical analysis alone.

  8. Study of bipolar pulsed plasma electrolytic carbonitriding on nanostructure of compound layer for a gamma Ti-Al alloy

    Institute of Scientific and Technical Information of China (English)

    Mahmood ALIOFKHAZRAEI; Alireza SABOUR ROUHAGHDAM; Mohsen ROOHZENDEH

    2008-01-01

    The surface hardening of a gamma Ti-Al alloy by using bipolar pulsed nanocrystalline plasma electro-lytic carbonitriding has been studied in this investigation. Coating process was performed on a triethanolamine-based electrolyte by a cooling bath. The nanostructure of the obtained compound layer was examined with the figure analysis of the scanning electron microscopy (SEM) nanographs. The effects of the process variables, i.e., fre-quency, temperature of the electrolyte, applied voltage and treatment time, have been experimentally studied. Statistical methods were used to achieve the optimum size of the nanocrystals. Finally, the contribution percentage of the effective factors of the pulsed current was revealed, and the confirmation run showed the validity of the obtained results.

  9. Steroidal hormones and other endocrine active compounds in shallow groundwater in nonagricultural areas of Minnesota—Study design, methods, and data, 2009–10

    Science.gov (United States)

    Erickson, Melinda L.

    2012-01-01

    The U.S. Geological Survey, in cooperation with the Minnesota Pollution Control Agency, completed a study on the occurrence of steroidal hormones and other endocrine active compounds in shallow groundwater in nonagricultural areas of Minnesota during 2009–10. This report describes the study design and methods, and presents the data collected on steroidal hormones and other related compounds. Environmental and quality-control samples were collected from 40 wells as part of this study. Samples were analyzed by the U.S. Geological Survey National Water Quality Laboratory for 16 steroidal hormones and 4 other related compounds, of which all but 2 compounds are endocrine active compounds. Most of the water samples did not contain detectable concentrations of any of the 20 compounds analyzed. Water samples from three wells had detectable concentrations of one or more compounds. Bisphenol A was detected in samples from three wells, and trans-diethylstilbestrol was detected in one of the samples in which bisphenol A also was detected.

  10. Tuning the phase diagrams: the miscibility studies of multilactate liquid crystalline compounds

    Science.gov (United States)

    Bubnov, Alexej; Tykarska, Marzena; Hamplová, Věra; Kurp, Katarzyna

    2016-09-01

    Design of binary and multicomponent liquid crystalline mixtures is a very powerful tool to reach the desired self-assembling properties. Beyond many advantages, this method has a distinct negativity - it is very material-consuming. While working with unique chiral materials in the research laboratory, this problem can be solved by applying miscibility study by the contact preparation method. In this work, the miscibility studies of lactic acid derivatives and non-chiral/chiral liquid crystalline molecules of different structure have been done in order to establish the phase diagrams. Special attention is focused on the ferro(antiferro)electric smectic phases.

  11. A study to evaluate the levels of dioxin-like compounds in dairy feeds in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Lorber, M.; Ferrario, J.; Byrne, C. [United States Environmental Protection Agency, WA, DC (United States); Greene, C.; Cyrus, A. [Versar, Inc., Springfield, VA (United States)

    2004-09-15

    The primary route for general population exposure to dioxin-like compounds is through the consumption of animal fats, with bovine-derived meat, milk and dairy products comprising over 50% of total exposure in the United States. The primary route of exposure hypothesized for cattle is airborne deposition of dioxins onto the leaves of feed crops. Over the last few years additional pathways of exposure have been identified associated with contaminated feed additives such as ball clay, mineral supplements, and animal byproducts. Studies by the United States Department of Agriculture (USDA) have shown that incidental contact with pentachlorophenol (PCP)-treated wood by cattle have resulted in elevated tissue levels. Although the air-to-leaf pathway is still considered by most researchers to be the dominant pathway of exposure, the lack of any systematic examination of animal feeds to quantify the contribution of the air-to-leaf pathway has been a major gap in our empirical understanding of dioxin exposure. The Environmental Protection Agency (EPA), in cooperation with USDA and the US Food and Drug Administration (FDA), has undertaken a program to study the presence of dioxin-like compounds in animal feeds. Two phases of this program have been completed, and this paper reports on the third phase. The first phase was a study on the mass balance of dioxins in lactating cows. The objective of that study was to quantify the role feeds play in total dairy cow exposure. The second phase of the program involved the collection and measurement of dioxins in minor feed components. Dioxins in specific targeted animal feed components of interest, including animal byproducts (beef, pork, poultry by-products, fish meal) and plant byproducts (deodorizer distillates from corn, soybean, peanut, cottonseed, and canola processers; cane and beet molasses), were measured. The third phase of the project, reported here, involved component sampling of dairy feeds around the US.

  12. Protein binding studies with radiolabeled compounds containing radiochemical impurities. Equilibrium dialysis versus dialysis rate determination

    DEFF Research Database (Denmark)

    Honoré, B

    1987-01-01

    The influence of radiochemical impurities in dialysis experiments with high-affinity ligands is investigated. Albumin binding of labeled decanoate (97% pure) is studied by two dialysis techniques. It is shown that equilibrium dialysis is very sensitive to the presence of impurities resulting...

  13. Studies of Compound States of Atomic Negative Ions Using Laser Beams

    Science.gov (United States)

    1984-07-01

    of experimental state. The results agree closely with the experimental and theoretical studies of the He- ion. value of 0.076 eV obtained by Oparin ...420 10 V. A. Oparin , R. N. Ilin, i. T. Serenkov and N. V. Fedorenko, (1968). Zh. Eksp. Teor. Fiz. Pis’ma Red. 12, 237 (1970) [JETP Lett. 25G. N. Estberg

  14. ATMOSPHERIC VOLATILE ORGANIC COMPOUND MEASUREMENTS DURING THE 1996 PASO DEL NORTE OZONE STUDY

    Science.gov (United States)

    Ambient air VOC samples were collected at surface air quality monitoring sites, near sources of interest, and aloft on the US (El Paso) and Mexican (Ciudad Juarez) side of the border during a six-week period of the 1996 Paso del Norte Ozone Study. Samples were collected at five...

  15. Charcoal and activated carbon as adsorbate of phytotoxic compounds - a comparative study.

    NARCIS (Netherlands)

    Hille, M.G.; Ouden, den J.

    2005-01-01

    This study compares the potential of natural charcoal from Scots pine (Pinus sylvestris L.) and activated carbon to improve germination under the hypothesis that natural charcoal adsorbs phytotoxins produced by dwarf-shrubs, but due to it's chemical properties to a lesser extent than activated carbo

  16. High pressure studies on uranium and thorium silicide compounds: Experiment and theory

    DEFF Research Database (Denmark)

    Yagoubi, S.; Heathman, S.; Svane, A.

    2013-01-01

    The actinide silicides ThSi, USi and USi2 have been studied under high pressure using both theory and experiment. High pressure synchrotron X-ray diffraction experiments were performed on polycrystalline samples in diamond anvil cells at room temperature and for pressures up to 54, 52 and 26 GPa...

  17. Short-term toxicity studies with triphenyltin compounds in rats and guinea-pigs

    NARCIS (Netherlands)

    Verschuuren, H.G.; Kroes, R.; Vink, H.H.; Esch, G.J. van

    1966-01-01

    Short-term toxicity studies have been carried out in rats and guinea-pigs fed diets containing triphenyltin acetate (TPTA), triphenyltin hydroxide (TPTH) or triethyltin hydroxide (TETH) for 90 days at levels ranging from 0 to 50 ppm. The lowest dietary levels found to retard growth in rats and guin

  18. Rock avalanche and rock glacier: A compound landform study from Hornsund, Svalbard

    Science.gov (United States)

    Hartvich, Filip; Blahut, Jan; Stemberk, Josef

    2017-01-01

    On the northern coast of the Hornsund fjord at SW Svalbard, numerous rock block accumulations flank the foot of Rotjesfjellet ridge. Whereas these accumulations are widely described as rock glaciers, this study shows that other factors also influence formation of these landforms. In this study, morphometric profiling and terrain analyses, lichenometry, optical granulometry, Schmidt hammer measurements, geophysical measurements using electric resistivity tomography, geodetic measurements using terrestrial LiDAR and rockfall modelling were used to clarify the formation of one unusual block accumulation. The morphometric analysis of a detailed (0.5 m) DEM and relief profiles showed distinctly different morphology of one of four studied block accumulations. The electric resistivity tomography revealed an ice core in the accumulation, the Schmidt hammer sampling helped to establish relatively younger age of the lobe-like left part of accumulation and finally, the lichenometry was employed to place the event on the approximate position on the timescale. In conclusion, the unusual block accumulation is a result of two consequent processes: first, a typical foothill rock glacier has developed, and consequently a large rock avalanche occurred, adding material and deforming the NW part of the accumulation. Based on the results of lichenometry, the rock avalanche was estimated to be 250 ± 50 years old. The study thus presents one of the few reported slope deformation events from the recently deglaciated Arctic areas.

  19. A theoretical study of the elastic and thermal properties of ScRu compound under pressure

    Science.gov (United States)

    Huang, Shuo; Li, Rui-Zi; Qi, San-Tao; Chen, Bao; Shen, Jiang

    2014-06-01

    The elastic and thermal properties of ScRu under pressure are studied using a first-principles pseudopotential method within the generalized gradient approximation. The calculated lattice parameter and formation enthalpy are in good agreement with the previous experimental and theoretical results. From the static finite strain technique, we obtained three independent elastic constants (C 11, C 12 and C 44) and various secondary elasticity parameters such as shear modulus, Young’s modulus and elastic anisotropy, as functions of pressure. This study also provided the pressure and temperature variations of the bulk modulus, Debye temperature, thermal expansion coefficient and heat capacity in wide pressure (0-60 GPa) and temperature (0-1800 K) ranges.

  20. The Role of Heterogeneous Chemistry of Volatile ORganic Compounds: A Modeling and Laboratory Study

    Energy Technology Data Exchange (ETDEWEB)

    Gregory R. Carmichael; Vicki H. Grassian

    2007-03-01

    Overview The outputs of this research have been reported annually via the RIMS system. This report serves as an update and final report. The focus of our DOE BES funded project is on the importance of heterogeneous reactions in the troposphere. The primary objectives of our study were to: (i) Evaluate the extent to which heterogeneous chemistry affects the photochemical oxidant cycle, particularly, sources and sinks of tropospheric ozone; and (ii) Conduct laboratory studies on heterogeneous reactions involving NOy, O3 and VOCs on aerosol surfaces. These objectives were pursued through a multidisciplinary approach that combines modeling and laboratory components as discussed in more detail below. In addition, in response to the reconfiguring of the Atmospheric Science Program to focus on aerosol radiative forcing of climate, we also began to investigate the radiative properties of atmospheric aerosol.