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1.
Environ Sci Pollut Res Int ; 31(22): 33107-33119, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38676870

RESUMEN

Layered double hydroxide (LDH) is an applicable material that can be modified in various ways. Modifications using natural extracts fulfill the principles of "green chemistry." The preparation of butterfly pea flower extract (BPE)-modified NiAl LDH was completed using the calcination and restacking method. The characteristics of the prepared composites were identified through analysis of functional groups, crystal phase, bandgap energy, surface area and surface morphology. Fourier transform-infrared (FT-IR) characterization revealed that the active group of the catalyst is -OH except for NiAl layered double oxide (LDO), which has the metal oxide-like functional groups. X-ray diffraction patterns expressed a typical layered material structure of NiAl LDH dan NiAl LDH-BPE, but not for NiAl LDO and NiAl LDO-BPE. Introducing BPE into NiAl LDH and NiAl LDO effectively decreased the bandgap energy and changed the surface morphology. The prepared catalysts were applied in a batch system with pH 5 to degrade tetracycline (TC). NiAl LDO demonstrated the highest activity as a catalyst in TC degradation, with a 93.61% degradation rate. In contrast, NiAl LDO-BPE demonstrated the highest structural stability in TC degradation and repeated use, with an initial degradation percentage of 82.58% and a fifth regeneration percentage of 71.4%.


Asunto(s)
Flores , Tetraciclina , Tetraciclina/química , Catálisis , Flores/química , Extractos Vegetales/química , Hidróxidos/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
2.
J Hazard Mater ; 415: 125635, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-33770681

RESUMEN

Nano-rod-shaped niobium oxide with a deformed orthorhombic structure (ortho-Nb2O5) is first demonstrated as a selective adsorbent to remove cationic dyes wastewater. Ortho-Nb2O5 quickly adsorbs methylene blue (MB) with much greater capacity than reported inorganic adsorbents. Furthermore, ortho-Nb2O5 has a stronger affinity to cationic dye than anionic dye because cation exchange is involved in the adsorption process. The dye molecule adsorbed onto ortho-Nb2O5 can be degraded entirely under UV light irradiation because of its photocatalytic properties. Moreover, the regenerated ortho-Nb2O5 shows high reusability for use in additional adsorption processing. As described herein, new insights into the use of ortho-Nb2O5 as a photocatalytically regeneratable adsorbent for wastewater treatment are presented.

3.
Chem Commun (Camb) ; 49(2): 134-6, 2013 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-23072826

RESUMEN

Alkyl iodides and tertiary silanes were successfully coupled with good functional group tolerance using a Pt(P(tBu)(3))(2)/(iPr)(2)EtN/CH(3)CN system. The utility of the methodology is demonstrated by the synthesis of silafluofen, a Si-containing insecticide.


Asunto(s)
Alcanos/química , Insecticidas/síntesis química , Yoduros/química , Platino (Metal)/química , Silanos/química , Catálisis , Insecticidas/química , Compuestos de Organosilicio/síntesis química , Compuestos de Organosilicio/química , Silanos/síntesis química
4.
Inorg Chem ; 51(2): 775-7, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-22221189

RESUMEN

Complexation of trinuclear oxo-centered carboxylates with a silicododecatungstate resulted in the formation of ionic crystals of [M(3)O(OOCC(6)H(5))(6)(H(2)O)(3)](4)[α-SiW(12)O(40)]·nH(2)O·mCH(3)COCH(3) [M = Cr (Ia), Fe (IIa)]. Treatments of Ia and IIa at 373 K in vacuo formed guest-free phases Ib and IIb, respectively. Compounds Ib and IIb heterogeneously catalyzed the pinacol rearrangement to pinacolone with high conversion at 373 K, and the catalysis is suggested to proceed size selectively in the solid bulk.

5.
Chemistry ; 16(45): 13519-27, 2010 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-21031364

RESUMEN

A convenient procedure has been developed for the preparation of Group 14 compounds by integrated palladium-catalyzed cross-coupling of aromatic iodides with the corresponding Group 14 hydrides in the presence of a base. The reaction conditions can be applied to the cross-coupling of tertiary, secondary, and primary Group 14 compounds. In most cases, the desired arylated products were obtained in synthetically useful yields. Even in the case of aryl iodides containing OH, NH(2), CN, or CO(2)R groups, the reactions proceeded with good to high yields with tolerance of these reactive functional groups. A possible application of this method is the unique synthesis of a fungicidal diarylmethyl(1H-1,2,4-triazol-1-ylmethyl)silane derivative.


Asunto(s)
Antifúngicos/síntesis química , Hidrocarburos Yodados/síntesis química , Paladio/química , Silanos/síntesis química , Triazoles/síntesis química , Antifúngicos/química , Antifúngicos/farmacología , Catálisis , Técnicas Químicas Combinatorias , Hidrocarburos Yodados/química , Hidrocarburos Yodados/farmacología , Estructura Molecular , Silanos/química , Silanos/farmacología , Triazoles/química , Triazoles/farmacología
6.
Chem Commun (Camb) ; 46(41): 7784-6, 2010 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-20871874

RESUMEN

The treatment of aryl iodides with tris(trimethylsilyl)silane in the presence of Pd(P(tBu)(3))(2) and the Hünig base leads to the formation of hypersilylated aromatic products in good to excellent yields without cleavage of weak Si-Si bonds under mild conditions.

7.
Inorg Chem ; 47(8): 3349-57, 2008 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-18311893

RESUMEN

The complexation of Keggin-type polyoxometalate [alpha-SiW 12O 40] (4-), macrocation [Cr 3O(OOCC 2H 5) 6(H 2O) 3] (+), and monovalent cation A (+) forms ionic crystals of A 2[Cr 3O(OOCC 2H 5) 6(H 2O) 3] 2[alpha-SiW 12O 40]. nH 2O [A = Na ( 1a), K ( 2a), Rb ( 3a), NH 4 ( 4a), Cs ( 5a), and tetramethylammonium (TMA) ( 6a)]. Single crystal (1a- 4a and 6a) and powder (5a) X-ray analyses have shown that the ionic crystals possess 2D layers of polyoxometalates and macrocations. Compounds 2a- 5a had almost the same structure, while the layers in 1a and 6a stack in different ways. The structures and sorption properties of 2b- 5b are investigated in more detail. The interlayer distances of guest free phases 2b- 5b increase with the increase in the ionic radii of the monovalent cations, which reside between the layers. Compounds 2b- 5b possess hydrophobic and hydrophilic channels, which exist between the layers and through the layers, respectively. The volumes of the hydrophobic channels increase in the order of 2b < 3b approximately 4b < 5b, and those of the hydrophilic channels increase in the order of 2b < or = 3b < or = 4b < 5b. Single-crystal X-ray structure analyses of 2a- 4a have shown that the water of crystallization resides in the hydrophilic channel. It is probable that the water of crystallization in 5a resides in the hydrophilic channel in the same manner as those in 2a- 4a since 2a- 5a have almost the same structure. The water vapor sorption profiles of 2b- 5b are approximately reproduced by a linear driving force model. Therefore, water molecules sorbed in 2b- 5b probably reside in the hydrophilic channel. The n-propanol sorption profiles are reproduced by the summation of the linear driving force model, showing that two independent barriers exist in the n-propanol sorption. The in situ IR spectra of n-propanol sorbed showed the presence of two n-propanol species. These data show that n-propanol is sorbed into both hydrophilic and hydrophobic channels. Compound 5b sorbs halocarbons in the hydrophobic channel, while 2b- 4b exclude them.

8.
J Am Chem Soc ; 128(44): 14240-1, 2006 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-17076481

RESUMEN

An ionic crystal of Cs2[Cr3O(OOCC2H5)6(H2O)3]2[alpha-SiW12O40].4H2O 1a with hydrophilic and hydrophobic channels has been designed and successfully synthesized. The guest-free phase 1b sorbs dichloromethane and water in the hydrophobic and hydrophilic channels, respectively. The rate and equilibrium amount of the dichloromethane sorption into the hydrophobic channel and those of water into the hydrophilic channel were independent of each other. The sorption properties can be applied to the channel-selective sorption and collection of hydrophobic (dichloromethane) and hydrophilic (water) molecules from the mixture.

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