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991.
Solar forcing on climate has been reported in several studies although the evidence so far remains inconclusive. Here, we analyze the stream flow of one of the largest rivers in the world, the Paraná in southeastern South America. For the last century, we find a strong correlation with the sunspot number, in multidecadal time scales, and with larger solar activity corresponding to larger stream flow. The correlation coefficient is r=0.78, significant to a 99% level. In shorter time scales we find a strong correlation with El Ni?o. These results are a step toward flood prediction, which might have great social and economic impacts. 相似文献
992.
Andrea Pasquali 《Journal of Pure and Applied Algebra》2019,223(8):3537-3553
If A and B are n- and m-representation finite k-algebras, then their tensor product is not in general -representation finite. However, we prove that if A and B are acyclic and satisfy the weaker assumption of n- and m-completeness, then Λ is -complete. This mirrors the fact that taking higher Auslander algebra does not preserve d-representation finiteness in general, but it does preserve d-completeness. As a corollary, we get the necessary condition for Λ to be -representation finite which was found by Herschend and Iyama by using a certain twisted fractionally Calabi–Yau property. 相似文献
993.
Carla Maria Mariano Fernandez Maurício Ferreira da Rosa Ana Claudia Aparecida Mariano Fernandez Wanessa de Campos Bortolucci Fabiana Borges Padilha Ferreira Giani Andrea Linde 《Natural product research》2020,34(5):731-735
AbstractThis study, was to evaluate the acaricidal effect of the essential oil (EO) and fractions (FR) obtained from Laurus nobilis leaves on Rhipicephalus (Boophilus) microplus. Eight fractions were obtained, however FR1: sabinene (37.83%), β-pinene (13.50%), 1,8-cineole (12.66%), α-pinene (12.56%) and FR8: α-terpineol (79.19%) were highlighted as to the larvicidal potential when submitted by Larval Packet Test. The EO was tested by the Adult Immersion Test, at concentrations of 200.00; 100.00 and 50.00?µL/mL caused mortality of engorged females, egg mass reduction and hatching inhibition. Two fractions are shown to be efficient in controlling larvae FR8 (LC50?=?0.13?µL/mL, LC99?=?0.51?µL/mL) and FR1 (LC50?=?0.20?µL/mL, LC99?=?0.56?µL/mL). The fractionation of EO was determinant to elucidate which compounds were responsible for the larvicidal potential. This study opens new perspectives to direct new bioassays with the compounds obtained in the fractionation, since they present high potential on cattle tick larvae. 相似文献
994.
Dr. Benjamin A. Chalmers Hui Xing Sevan Houston Dr. Charlotte Clark Dr. Sussan Ghassabian Dr. Andy Kuo Benjamin Cao Andrea Reitsma Cody‐Ellen P. Murray Dr. Jeanette E. Stok Dr. Glen M. Boyle Carly J. Pierce Stuart W. Littler Prof. David A. Winkler Prof. Paul V. Bernhardt Dr. Cielo Pasay Prof. James J. De Voss Prof. James McCarthy Prof. Peter G. Parsons Prof. Gimme H. Walter Prof. Maree T. Smith Prof. Helen M. Cooper Prof. Susan K. Nilsson Dr. John Tsanaktsidis Dr. G. Paul Savage Prof. Craig M. Williams 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(28):8491-8491
995.
Marco Bortoluzzi Andrea Reolon Alberto Scrivanti Francesco Enrichi 《Chemical Papers》2018,72(4):809-819
Coordination compounds having formulae [M(MA)3] n and M(MA)(Me2Tp)2 (M = Y, Eu, Tb; MA = conjugate base of malonaldehyde; Me2Tp = tris(3,5-dimethyl-pyrazol-1-yl)borate) were synthesized and characterized. The photoluminescence features of the europium and terbium derivatives were investigated. By comparing the herein reported photoluminescence data with those relative to analogous nitro- and bromomalonaldehyde derivatives, it appears that the conjugate base of malonaldehyde is a more efficient antenna-ligand for the sensitization of Tb(III) luminescence. The experimental data were rationalized on the basis of DFT calculations. Tb(MA)(Me2Tp)2 was used as dopant for the preparation of luminescent plastic materials based on poly(methyl methacrylate). 相似文献
996.
Enzymatic or In Vivo Installation of Propargyl Groups in Combination with Click Chemistry for the Enrichment and Detection of Methyltransferase Target Sites in RNA 下载免费PDF全文
997.
Dr. Jens Langer Dr. Andrea Hamza Dr. Imre Pápai 《Angewandte Chemie (International ed. in English)》2018,57(9):2455-2458
The synthesis of a new iridium(I) complex containing an enamido phosphine anion (dbuP?) and its unique reactivity with CO2 is reported. The complex binds two equivalents of CO2 and initiates a highly selective reaction cascade. The reaction leads to the reversible cleavage of CO2 and the enamido ligand as well. Computational analysis points to the existence of a relatively stable Ir‐CO2 complex as a reaction intermediate prior to CO2 cleavage, which was confirmed experimentally. The observed transformation resembles several aspects of enzymatic CO2 fixation by RuBisCO. 相似文献
998.
Maria Annunziata M. Capozzi Andrea Bottoni Matteo Calvaresi Cosimo Cardellicchio 《Tetrahedron》2018,74(16):2041-2047
Pentafluorobenzyl pentafluorophenyl sulfide is oxidised with moderate e.e. value and a low yield by the usually highly successful oxidation protocol based upon tert-butyl hydroperoxide (TBHP) in the presence of a titanium/hydrobenzoin complex. This disappointing result resisted until the present work, in which the switch of the oxidation agent (from TBHP to cumene hydroperoxide), suggested by our previous computations, yielded the enantiopure sulfoxide. This valuable chiral compound was obtained in good yields (76%) without resorting to a chromatographic separation. DFT computations uncovered that this favourable reactivity was originated by a stabilizing π?π?stacking between the phenyl group of the oxidant and the pentafluorophenyl moiety of the substrate. 相似文献
999.
1000.
We deal with weighted inequalities of the type [formula] where: T is either the HardyLittlewood maximal operator or asingular integral operator; G is any measurable subset of Rn; f is any measurable function, vanishing outside G, such thatTf is well-defined; v and w are weights, that is, nonnegativelocally integrable functions on G; p, q(1, ). 1991 Mathematics Subject Classification 42B20, 42B25. 相似文献