A new efficient and practical method for the room-temperature reduction of aromatic nitro compounds employing FeSO4. 7H2O, NaBH4, H3PW12O40 system in H2O under mild conditions is reported. The method is simple, inexpensive, easily scaled-up and applicable for the large scale preparation of different substituted anilines.

The production of carboxylic acids by partial wet oxidation of alkali lignin at elevated temperatures and pressures was studied experimentally. Two different heteropoly acids, phosphotungstic acid (H₃PW12O40) and phosphomolybdic acid (H₃PMo12O40), were used to catalyze the oxidation of lignin under hydrothermal conditions. Factors influencing the total yield of carboxylic acids formed during th...

This paper reviews various types of heterogeneous acid-base catalysts for fragrances preparation. Catalytic activities of the various types of heterogeneous acid and base catalysts in fragrances preparation, i.e. nonzeolitic, zeolitic, and mesoporous molecular sieves, have been reported. Generally, heterogeneous acid catalysts are more commonly used in fragrance synthesis as compared to heterog...

Abstract Depletion of fossil fuels resources has triggered more research on finding potential alternative sources that are sustainable such as biomass waste. However, deconstruction the complex waste into desired products is too challenging and usually require a strong catalyst with great hydrolysing property. Common acids sulphuric acid, hydrochloric acid nitric were most studies for conversio...

In order to develop an efficient method by which eliminate NOx pollution, several new catalyst systems including different heteropolyacids (HPAs) and supported phosphotungstic acids (HPWs) (HPW/SiO2, HPW/SnO2, HPW/USY HPW/ZSM-5) for adsorption-decomposition of were prepared studied. The obtained catalysts characterized using a Brunauer-Emmett-Teller (BET) measurement Fourier transform infrared ...

The chemistry of polyoxometalates has been reviewed extensively. Much useful information about the synthesis, study of structures and various applications of heteropoly acids and their salts have been reported in the literature. Thus, POMs inorganic complexes composed of transitional metals mainly Mo, W and V. The present review gives an introduction into the chemistry of these compounds and ov...

Este artigo apresenta os resultados da determinação de 12 hidrocarbonetos policíclicos aromáticos (HPAs) em material particulado atmosférico (MPA) coletado na cidade de Niterói, RJ, Brasil. Amostras quinzenais de MPA foram coletadas durante 24 h, entre junho/2005 e maio/2006, no Campus da Universidade Federal Fluminense, localizado em uma área residencial e comercial no Centro de Niterói. Um am...

The present study investigates modified Mo/V/W mixed oxides as a possible alternative for state of the art heteropoly acid catalysts (HPA) in partial oxidation methacrolein (MAC) to methacrylic (MAA). Even though HPAs show an excellent activity and MAA selectivity, their long-term stability is unsatisfying, rendering catalyst inoperable after runtimes roughly 6 months. consisting M1 hexagonal (...

BACKGROUND Human platelet antigens (HPAs) are polymorphisms in platelet membrane glycoproteins (GPs) that can stimulate production of alloantibodies once exposed to foreign platelets (PLTs) with different HPAs. These antibodies can cause neonatal alloimmune thrombocytopenia, posttransfusion purpura, and PLT transfusion refractoriness. Most HPAs are localized on the main PLT receptors: 1) integr...