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331.
Alvaro J. Pardey José Brito María Fernández Angel B. Rivas Marisol C. Ortega Clementina Longo Pablo J. Baricelli Eduardo Lujano Sergio A. Moya 《Reaction Kinetics and Catalysis Letters》2001,74(1):111-118
Reported here is the influence of the reaction conditions variation (1-hexene/rhodium content (S/C) = 16 - 105, temperature (T) = 70 - 110 °C and carbon monoxide pressure (P(CO)) = 0.6 - 1.8 atm) on the catalytic hydroformylation of 1-hexene to aldehydes (heptanal and 2-methyl-hexanal) by the rhodium(I)
complex, [Rh(COD)(2-picoline)2]PF6 (COD = 1,5-cyclooctadiene)immobilized on poly(4-vinylpyridine) in contact with 10 mL of 80% aqueous 2-ethoxyethanol, under
water gas shift reaction condition.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
332.
Anna C. R. Moo Pedro H. Guedes Jos M. R. Flauzino Heliane S. daSilva Jussara G. Vieira Ana C. H. Castro rica V. R. Gomes Fernanda M. Tolentino Mrcia M. C. N. Soares Joo M. Madurro Ana G. Brito‐Madurro 《Electroanalysis》2019,31(8):1580-1587
This work describes an electrochemical genosensor for detection of genomic RNA of Zika virus in real samples of infected patients, using a new platform based on graphite electrodes modified with electrochemically reduced graphene oxide and polytyramine‐conducting polymer. The developed genosensor was suitable for differentiation between samples of healthy and infected patients with Zika virus by differential pulse voltammetry, detecting up to 0.1 fg/mL (1.72 copies/mL), showing good stability (about 60 days), rapid analysis (about 20 min) and potential for filling the lack of practical diagnostic methods for Zika virus. 相似文献
333.
Pedro Modesto Nascimento Menezes Henrique Ribeiro de Oliveira Mariana Coelho Brito Gabriela Olinda de Paiva Luciano Augusto de Almeida Ribeiro Angélica Maria Lucchese 《Natural product research》2019,33(17):2571-2573
Lippia thymoides (‘alecrim-do-mato’ or ‘alecrim-do-campo’) is used in Brazilian folk medicine to treat various illnesses, including diarrhea. This work aimed to evaluate in vitro spasmolytic and in vivo antidiarrheal activities of the L. thymoides essential oil (OOS) and to correlate with the traditional use of this plant. In isolated guinea-pig ileum, OOS presented a concentration-dependent spasmolytic activity in preparations pre-contracted with KCl 40 mM [EC50 = 16.89 (11.56–24.66) μg/mL], and antagonized phasic contractions induced by 1 μM carbachol [IC50 = 42.71 (37.35–48.83) μg/mL] or histamine [IC50 = 32.38 (27.44–38.20) μg/mL]. In mice, OOS at 400 mg/kg reduced intestinal transit, at 200 and 400 mg/kg reduced total stool mass and at 400 mg/kg reduced intestinal fluid accumulation. It was shown that the antidiarrheal effect of OOS is related to the inhibition of smooth muscle contraction and may be due to the presence of major compound β-caryophyllene in this essential oil. 相似文献
334.
Salt decay is one of the most harmful and complex deterioration mechanisms of porous building materials in architectural heritage. Despite several decades of research, it is still insufficiently understood, which hampers the development of effective treatments and prediction models. One key aspect is the influence soluble salts have on the evaporative drying of porous materials. It is often observed, for example, that drying is slower for higher salt concentrations. However, there is still no consensus as to why it happens. In this article, we examine experimentally the drying kinetics of three natural stones impregnated with solutions of sodium chloride or sodium nitrate with different concentrations. The method consisted of the following sequence of determinations: capillary absorption, drying kinetics, vapour pressure and vapour conductivity. It also included a morphological analysis of the efflorescence formed during drying. We have concluded that the slower drying rate was mainly due to the reduced sorptivity that arises at higher salt concentrations. In the cases where compact salt crusts formed on the surface of the stone, there was an additional reduction in the drying rate because these crusts obstructed vapour transport. However, in most cases, efflorescence was porous and had negligible obstructive effects. Efflorescence morphology is conditioned by well-determined causal factors, such as porosity, pore size and mineralogical structure of the stone, or the type of salt and its concentration. Here, it also revealed that it incorporated a component of unpredictability. This suggests that it may be necessary to move beyond purely deterministic approaches to salt decay. 相似文献
335.
336.
Coutinho LH Cavasso-Filho RL Rocha TC Homem MG Figueira DS Fonseca PT Cruz FC Naves de Brito A 《Physical review letters》2004,93(18):183001
We investigate the angular distribution of photoionization fragments at low photon energies (12-40 eV) in an open shell atom, by synchrotron radiation recoil ion momentum spectroscopy in a laser cooled and trapped sample. For cesium atoms, for which relativistic effects play an important role and the ion recoil is relatively small, we could determine large and rapid changes of the asymmetry parameter beta from two, observed for s electrons outside resonances and far from the Cooper minimum. They can be explained by relativistic effects and interchannel coupling arising from final state configuration mixing. 相似文献
337.
The majority of LGCAs has spurious conservation laws, the so-called staggered invariants, first discovered by Kadanoff, McNamara, and Zanetti. Consequently there are additional hydrodynamic modes of diffusive type, which modify mode coupling theories and the nonlinear fluid dynamic equations. The diffusivities of these staggered modes are evaluated in the mean field approximation for LGCAs on triangular lattices, starting from the Green-Kubo formulas for the staggered diffusivities. 相似文献
338.
339.
E.W. Dias A.P. Baêta Scarpelli L.C.T. Brito M. Sampaio M.C. Nemes 《The European Physical Journal C - Particles and Fields》2008,55(4):667-681
We extend a constrained version of implicit regularization (CIR) beyond one-loop order for gauge field theories. In this framework,
the ultraviolet content of the model is displayed in terms of momentum loop integrals order by order in perturbation theory
for any Feynman diagram, while the Ward–Slavnov–Taylor identities are controlled by finite surface terms. To illustrate, we
apply CIR to massless abelian gauge field theories (scalar and spinorial QED) to two-loop order and calculate the two-loop
beta-function of spinorial QED.
PACS 11.10.Gh; 11.15.Bt; 11.15.-q 相似文献
340.
Tainá Caroline dos Santos Kaline de Brito Sousa Lucas Andreo Andreia Martinelli Maria Fernanda Setubal Destro Rodrigues Sandra Kalil Bussadori Kristianne Porta Santos Fernandes Raquel Agnelli Mesquita-Ferrari 《Photochemistry and photobiology》2020,96(4):906-916
Moderate levels of a proinflammatory macrophages phenotype are indispensable and play an important role in the skeletal muscle repair process since this response depends on their secreted products concentration to influence and modulate muscle inflammation as well as the differentiation of myoblasts. This study investigated the effects of photobiomodulation (PBM) on undifferentiated and differentiation-induced C2C12 myoblasts cultivated in different concentrations of M1 phenotype macrophage-conditioned media of J774 cells (MCM1) also submitted to PBM using the same irradiation parameters. Irradiation was performed once with low-level laser (780 nm, 70 mW, 1 J) and was evaluated cell viability, proliferation and differentiation, nitric oxide (NO) synthesis and IL-6 and TNF-α protein levels 24 and 48 h after C2C12 irradiation. PBM treatment in undifferentiated myoblasts exhibited lower IL-6 levels in the presence of nonirradiated MCM1 at both concentrations. Myoblasts in proliferation condition cultivated with irradiated MCM1 showed lower IL-6 and TNF-α levels after 48 h in the presence of both concentrations evaluated. PBM induced a decrease in the synthesis of NO on undifferentiated and differentiation-induced myoblasts. PBM was able to reduce the level of proinflammatory protein and markers, which are important to allow the differentiation of myoblasts during the muscle repair process. 相似文献