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101.
Norma Ruiz-Torres Antonio Flores-Naveda Enrique Díaz Barriga-Castro Neymar Camposeco-Montejo Sonia Ramírez-Barrn Fernando Borrego-Escalante Guillermo Nio-Medina Agustín Hernndez-Jurez Carlos Garza-Alonso Pablo Rodríguez-Salinas Josu I. García-Lpez 《Molecules (Basel, Switzerland)》2021,26(7)
The objective of this study was to determine the oxidative stress and the physiological and antioxidant responses of coriander plants (Coriandrum sativum) grown for 58 days in soil with zinc oxide nanoparticles (ZnO NPs) and zinc sulfate (ZnSO4) at concentrations of 0, 100, 200, 300, and 400 mg of Zn/kg of soil. The results revealed that all Zn compounds increased the total chlorophyll content (CHLt) by at least 45%, compared to the control group; however, with 400 mg/kg of ZnSO4, chlorophyll accumulation decreased by 34.6%. Zn determination by induction-plasma-coupled atomic emission spectrometry (ICP–AES) showed that Zn absorption in roots and shoots occurred in plants exposed to ZnSO4 at all concentrations, which resulted in high levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA). Only at 400 mg/kg of ZnSO4, a 78.6% decrease in the MDA levels was observed. According to the results, the ZnSO4 treatments were more effective than the ZnO NPs to increase the antioxidant activity of catalase (CAT), ascorbate peroxidase (APX), and peroxidases (POD). The results corroborate that phytotoxicity was higher in plants subjected to ZnSO4 compared to treatments with ZnO NPs, which suggests that the toxicity was due to Zn accumulation in the tissues by absorbing dissolved Zn++ ions. 相似文献
102.
Quentin Vanbellingen Paul Servin Anaïs Coinaud Sonia Mallet-Ladeira Rgis Laurent Anne-Marie Caminade 《Molecules (Basel, Switzerland)》2021,26(8)
Pyridine, pyridine imine, and bipyridine imine ligands functionalized by a phenol have been synthesized and characterized, in many cases by X-ray diffraction. Several of these N-, N,N-, and N,N,N,-ligands have been grafted onto the surface of phosphorhydrazone dendrimers, from generation 1 to generation 3. The complexation ability of these monomers and dendrimers towards palladium(II) has been assayed. The corresponding complexes have been either isolated or prepared in situ. In both cases, the monomeric and dendritic complexes have been tested as catalysts in Heck couplings and in Sonogashira couplings. In some cases, a positive dendritic effect has been observed, that is, an increase of the catalytic efficiency proportional to the dendrimer generation. 相似文献
103.
Iodice M Cusanno F Acha A Ambrozewicz P Aniol KA Baturin P Bertin PY Benaoum H Blomqvist KI Boeglin WU Breuer H Brindza P Bydzovský P Camsonne A Chang CC Chen JP Choi S Chudakov EA Cisbani E Colilli S Coman L Craver BJ De Cataldo G de Jager CW De Leo R Deur AP Ferdi C Feuerbach RJ Folts E Fratoni R Frullani S Garibaldi F Gayou O Giulani F Gomez J Gricia M Hansen JO Hayes D Higinbotham DW Holmstrom TK Hyde CE Ibrahim HF Jiang X Kaufman LJ Kino K Kross B Lagamba L LeRose JJ Lindgren RA 《Physical review letters》2007,99(5):052501
An experiment measuring electroproduction of hypernuclei has been performed in hall A at Jefferson Lab on a 12C target. In order to increase counting rates and provide unambiguous kaon identification two superconducting septum magnets and a ring imaging Cherenkov detector were added to the hall A standard equipment. An unprecedented energy resolution of less than 700 keV FWHM has been achieved. Thus, the observed (Lambda)(12)B spectrum shows for the first time identifiable strength in the core-excited region between the ground-state s-wave Lambda peak and the 11 MeV p-wave Lambda peak. 相似文献
104.
Tvaskis V Christy ME Arrington J Asaturyan R Baker OK Blok HP Bosted P Boswell M Bruell A Cochran A Cole L Crowder J Dunne J Ent R Fenker HC Filippone BW Garrow K Gasparian A Gomez J Jackson HE Keppel CE Kinney E Lapikás L Liang Y Lorenzon W Lung A Mack DJ Martin JW McIlhany K Meekins D Milner RG Mitchell JH Mkrtchyan H Moreland B Nazaryan V Niculescu I Opper A Piercey RB Potterveld DH Rose B Sato Y Seo W Smith G Spurlock K van der Steenhoven G Stepanyan S Tadevosian V Uzzle A Vulcan WF Wood SA 《Physical review letters》2007,98(14):142301
We report on a study of the longitudinal to transverse cross section ratio, R=sigmaL/sigmaT, at low values of x and Q2, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Laboratory Hall C spanning the four-momentum transfer range 0.06相似文献
105.
We present specific heat data on three samples of the dilute Ising magnet LiHoxY1-xF4 with x=0.018, 0.045, and 0.080. Previous measurements of the ac susceptibility of an x=0.045 sample showed the Ho3+ moments to remain dynamic down to very low temperatures, and the specific heat was found to have unusually sharp features. In contrast, our measurements do not exhibit these sharp features in the specific heat and instead show a broad feature, for all three samples studied, which is qualitatively consistent with a spin glass state. Integrating C/T, however, reveals an increase in residual entropy with lower Ho concentration, consistent with recent Monte Carlo simulations showing a lack of spin glass transition for low x. 相似文献
106.
Del Sordo Filho Giovanni Torrecilha Jefferson Koyaishi Scapin Marcos Antônio Oliveira Sonia Maria Barros da Silva Paulo Sergio Cardoso 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):61-70
Journal of Radioanalytical and Nuclear Chemistry - This study has evaluated chemical, radiological composition and determined the cation exchange capacity (CEC) for three commercially available... 相似文献
107.
108.
Access to Optically Active 3‐Substituted Piperidines by Ring Expansion of Prolinols and Derivatives
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Dr. Domingo Gomez Pardo Prof. Janine Cossy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(16):4516-4525
The ring expansion of prolinols via an aziridinium intermediate gives C3‐substituted piperidines in good yields and enantiomeric excess, the substituent at the C3 position being derived from the most reactive nucleophile in the reaction mixture. Depending on the nucleophile, the reaction proceeds under thermodynamic or kinetic control. The regioselectivity of attack of nucleophiles on the aziridinium intermediate depends on the nature of the substituents on the nitrogen atom and the C4 position of the starting prolinols. 相似文献
109.
Water‐Stable Zirconium‐Based Metal–Organic Framework Material with High‐Surface Area and Gas‐Storage Capacities
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Dr. Oleksii V. Gutov Dr. Wojciech Bury Dr. Diego A. Gomez‐Gualdron Dr. Vaiva Krungleviciute Dr. David Fairen‐Jimenez Dr. Joseph E. Mondloch Dr. Amy A. Sarjeant Salih S. Al‐Juaid Prof. Dr. Randall Q. Snurr Prof. Dr. Joseph T. Hupp Prof. Dr. Taner Yildirim Prof. Dr. Omar K. Farha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(39):12389-12393
We designed, synthesized, and characterized a new Zr‐based metal–organic framework material, NU‐1100 , with a pore volume of 1.53 ccg?1 and Brunauer–Emmett–Teller (BET) surface area of 4020 m2g?1; to our knowledge, currently the highest published for Zr‐based MOFs. CH4/CO2/H2 adsorption isotherms were obtained over a broad range of pressures and temperatures and are in excellent agreement with the computational predictions. The total hydrogen adsorption at 65 bar and 77 K is 0.092 g g?1, which corresponds to 43 g L?1. The volumetric and gravimetric methane‐storage capacities at 65 bar and 298 K are approximately 180 vSTP/v and 0.27 g g?1, respectively. 相似文献
110.
Enhanced π‐Backdonation from Gold(I): Isolation of Original Carbonyl and Carbene Complexes
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Dr. Maximilian Joost Dr. Laura Estévez Sonia Mallet‐Ladeira Dr. Karinne Miqueu Dr. Abderrahmane Amgoune Dr. Didier Bourissou 《Angewandte Chemie (International ed. in English)》2014,53(52):14512-14516
The specific electronic properties of bent o‐carborane diphosphine gold(I) fragments were exploited to obtain the first classical carbonyl complex of gold [(DPCb)AuCO]+ (ν(CO)=2143 cm?1) and the diphenylcarbene complex [(DPCb)Au(CPh2)]+, which is stabilized by the gold fragment rather than the carbene substituents. These two complexes were characterized by spectroscopic and crystallographic means. The [(DPCb)Au]+ fragment plays a major role in their stability, as substantiated by DFT calculations. The bending induced by the diphosphine ligand substantially enhances π‐backdonation and thereby allows the isolation of carbonyl and carbene complexes featuring significant π‐bond character. 相似文献