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91.
B. de Castro C. Freire M. Teresa Duarte M. F. Minas da Piedade I. C. Santos 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):370-372
In the title complex, trans‐{2,2′‐[cyclohexane‐1,2‐diylbis(nitrilomethylidyne)]diphenolato‐κ4O,N,N′,O′}nickel(II)–chloroform (1/1), [Ni(C20H20N2O2)]·CHCl3, the Ni atom has a square‐planar geometry, slightly tetrahedrally distorted. The Ni—N and Ni—O bonding distances are within the expected ranges for Ni–Schiff base derivatives. The diimine bridge has a gauche conformation with the cyclohexyl ring almost coplanar with the NiN2O2 plane. The complex molecules pack in dimers with an Ni?Ni distance of 3.59 (1) Å and form a three‐dimensional structure displaying a herring‐bone configuration. Channels are occupied by solvent molecules, which are involved in C—H?O hydrogen bonds with the ligand O atoms. 相似文献
92.
de Castro RA Canotilho J Barbosa RM Redinha JS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,67(5):1194-1200
The molecular structure of conformational isomorphs given by X-ray diffraction for racemic and enantiomeric atenolol were optimized at the HF/6-31G* level of theory and the infrared spectra of the structure were calculated. These spectra are used to characterize the differences between the various atenolol conformers. The spectra of the (R,S)- and S-atenolol solid forms were recorded and the bands corresponding to the functional groups identified with the aid of the calculated spectra, fitting analysis, temperature effect and H/D isotopic exchange. Particular attention was paid to the stretch vibration modes of the functional groups present in the atenolol. 相似文献
93.
Elvio A. Campos Yoshitaka Gushikem Maria do Carmo Gonçalves Sandra C. de Castro 《Journal of colloid and interface science》1996,180(2):453
The Nb2O5/cellulose composite was prepared by reacting α-cellulose with NbCl5-n(OC2H5)n, in nonaqueous solvent, under nitrogen atmosphere and submitting the obtained material to hydrolysis. An increase in the crystallinity degree is observed in the composite material because the precursor reagent reacts with the amorphous phase of the cellulose fibers. Loadings between 4.5 and 16.0% of the oxide were achieved and in every case the oxide particles uniformly cover the fiber surface. Lewis and Brønsted acid sites were determined by using pyridine as the basic molecular probe. 相似文献
94.
Yang Xin Dr. Boxuan Shen Prof. Mauri A. Kostiainen Prof. Guido Grundmeier Prof. Mario Castro Dr. Veikko Linko Dr. Adrian Keller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(33):8564-8571
The surface-assisted hierarchical assembly of DNA origami nanostructures is a promising route to fabricate regular nanoscale lattices. In this work, the scalability of this approach is explored and the formation of a homogeneous polycrystalline DNA origami lattice at the mica-electrolyte interface over a total surface area of 18.75 cm2 is demonstrated. The topological analysis of more than 50 individual AFM images recorded at random locations over the sample surface showed only minuscule and random variations in the quality and order of the assembled lattice. The analysis of more than 450 fluorescence microscopy images of a quantum dot-decorated DNA origami lattice further revealed a very homogeneous surface coverage over cm2 areas with only minor boundary effects at the substrate edges. At total DNA costs of € 0.12 per cm2, this large-scale nanopatterning technique holds great promise for the fabrication of functional surfaces. 相似文献
95.
Laís Peres Silva Ivanilson Pimenta Santos Dahara Keyse Carvalho Silva Bruna Padilha Zurita Claro dos Reis Cssio Santana Meira Marcos Venícius Batista de Souza Castro Jos Maurício dos Santos Filho Joo Honorato de Araujo-Neto Javier Alcides Ellena Rafael Gomes da Silveira Milena Botelho Pereira Soares 《Molecules (Basel, Switzerland)》2022,27(23)
Immunomodulatory agents are widely used for the treatment of immune-mediated diseases, but the range of side effects of the available drugs makes necessary the search for new immunomodulatory drugs. Here, we investigated the immunomodulatory activity of new ferrocenyl-N-acyl hydrazones derivatives (SintMed(141–156). The evaluated N-acyl hydrazones did not show cytotoxicity at the tested concentrations, presenting CC50 values greater than 50 µM. In addition, all ferrocenyl-N-acyl hydrazones modulated nitrite production in immortalized macrophages, showing inhibition values between 14.4% and 74.2%. By presenting a better activity profile, the ferrocenyl-N-acyl hydrazones SintMed149 and SintMed150 also had their cytotoxicity and anti-inflammatory effect evaluated in cultures of peritoneal macrophages. The molecules were not cytotoxic at any of the concentrations tested in peritoneal macrophages and were able to significantly reduce (p < 0.05) the production of nitrite, TNF-α, and IL-1β. Interestingly, both molecules significantly reduced the production of IL-2 and IFN-γ in cultured splenocytes activated with concanavalin A. Moreover, SintMed150 did not show signs of acute toxicity in animals treated with 50 or 100 mg/kg. Finally, we observed that ferrocenyl-N-acyl hydrazone SintMed150 at 100 mg/kg reduced the migration of neutrophils (44.6%) in an acute peritonitis model and increased animal survival by 20% in an LPS-induced endotoxic shock model. These findings suggest that such compounds have therapeutic potential to be used to treat diseases of inflammatory origin. 相似文献
96.
Varietal compounds have been analyzed in wines prepared in the laboratory from four grape varieties grown in Spain. The possibilities for enhancing their aroma afforded by addition of glycosidase enzymes and steeping with the skin were studied. Both treatments increased substances responsible for varietal aroma in all wines, the effect being particularly significant for benzyl alcohol. 相似文献
97.
Gabriele Albertin Stefano Antoniutti Jesús Castro Francesca Sibilla 《无机化学与普通化学杂志》2019,645(8):638-644
Imine complexes [IrCl(η5‐C5Me5){κ1‐NH=C(H)Ar}{P(OR)3}]BPh4 ( 1 , 2 ) (Ar = C6H5, 4‐CH3C6H4; R = Me, Et) were prepared by allowing chloro complexes [IrCl2(η5‐C5Me5){P(OR)3}] to react with benzyl azides ArCH2N3. Bis(imine) complexes [Ir(η5‐C5Me5){κ1‐NH=C(H)Ar}2{P(OR)3}](BPh4)2 ( 3 , 4 ) were also prepared by reacting [IrCl2(η5‐C5Me5){P(OR)3}] first with AgOTf and then with benzyl azide. Depending on the experimental conditions, treatment of the dinuclear complex [IrCl2(η5‐C5Me5)]2 with benzyl azide yielded mono‐ [IrCl2(η5‐C5Me5){κ1‐NH=C(H)Ar}] ( 5 ) and bis‐[IrCl(η5‐C5Me5){κ1‐NH=C(H)Ar}2]BPh4 ( 6 ) imine derivatives. In contrast, treatment of chloro complexes [IrCl2(η5‐C5Me5){P(OR)3}] with phenyl azide C6H5N3 gave amine derivatives [IrCl(η5‐C5Me5)(C6H5NH2){P(OR)3}]BPh4 ( 7 , 8 ). The complexes were characterized spectroscopically (IR, NMR) and by X‐ray crystal structure determination of [IrCl(η5‐C5Me5){κ1‐NH=C(H)C6H4‐4‐CH3}{P(OEt)3}]BPh4 ( 2b ). 相似文献
98.
99.
An ethanol process based on a gas-lift tower fermenter arrangement was used as a model system to show the strong dependence of reactor behavior on the developing chemical environment within the reactor. The reactor performance limits for realistic substrates—starch and molasses—are characterized and compared with those attainable on an ideal substrate, glucose.
相似文献100.
A continuous method, easy to automate, for the determination of anthocyanins in wine based on the coupling of continuous liquid–solid extraction, evaporation, HPLC individual separation and photometric detection is proposed. The target analytes are removed from the wine in a continuous fashion using a C18 minicolumn and eluted with an aqueous solution (pH 2) with 16% acetonitrile. The eluted fraction is concentrated by solvent evaporation assisted by heat and dragging off the vapour using a flow of N2. For in-line preconcentration, a continuous evaporation module was designed and located in the manifold between the solid-phase minicolumn and the injection valve of the chromatograph. In this way, injection of the sample into the dynamic system leads the plug through it for liquid–solid extraction of the anthocyanins, partial evaporation of the eluent (with a preconcentration factor as required) and transport to the high-pressure injection valve of the chromatograph, where individual separation and subsequent photometric detection take place. The method thus developed for the determination of malvidin-3-glucoside, cyanidin-3-glucoside and peonidin-3-glucoside anthocyanins in Spanish red wines is more sensitive than the batch manual method based on the same steps, has better linearity of the calibrations curves with lower detection limits and much wider determination range for the most abundant anthocyanins in wine. In addition, the method can be fully automated with low acquisition and maintenance costs. 相似文献