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1.
RSC Adv ; 13(47): 33390-33402, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37964904

RESUMO

The purpose of this review is to summarize the current literature on reductive C-N coupling of nitro compounds and boronic acids, with special emphasis on the mechanistic features of the reactions. The metal-catalyzed reactions are discussed first. This is followed by electro-synthesis and organophosphorus-catalyzed reactions. Finally, the available examples of catalyst-free reactions will be covered at the end of this review.

2.
RSC Adv ; 12(47): 30564-30576, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36337948

RESUMO

In this review, we have discussed recent developments on the direct selenosulfonylation of unsaturated compounds which lead to the formation of two new carbon-sulfur and carbon-selenium bonds in a single operation. The reactions were classified based on the type of starting unsaturated compound and product. Thus, the review is divided into three major sections. The first describes the current literature on selenosulfonylation of alkenes. The second section covers the available literature on selenosulfonylation of alkynes. The third focuses exclusively on selenosulfonylation of allenes.

3.
Food Chem ; 373(Pt A): 131442, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34715627

RESUMO

In this study, electromembrane extraction (EME) combined with micro-EME (µ-EME) was used for the selective extraction of Cr(VI) from food samples (milk powder, Ocimum basilicum, and fish samples). Electrothermal atomic absorption spectrometry was used for the quantification of Cr(VI). Under the optimized extraction conditions, the extraction recovery of Cr(VI) was 73.7%. This proposed method provided a linear range from 0.01 to 5.0 ng/mL and the limit of detection (LOD) and limit of quantification (LOQ) were 0.003 and 0.010 ng/mL. The %RSD (n = 5) was in the range of 11.2-11.8% at 0.05, 1.0 and 2.5 ng/mL of Cr(VI), and the enrichment factor was 584. The accuracy of the method was evaluated by analysis of SRM 2700 as a certified reference material (CRM) and result was in good agreement with the certified value.


Assuntos
Cromo , Animais , Limite de Detecção , Espectrofotometria Atômica
4.
Environ Monit Assess ; 190(8): 474, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30022379

RESUMO

The present study was conducted, based on scenario modeling approach, in the Do-hezar and Se-hezar forested landscape in the Mazandaran Province in Northern Iran in order to detect spatial-temporal changes of carbon storage and sequestration in four different carbon pools, i.e., aboveground and belowground biomasses, dead organic matter, and organic soils. For this purpose, firstly, the changing trend of land use/land cover (LULC) was detected by analyzing and comparing remotely sensed data of the landscape during the period of 1984-2016. Then, the impacts of future LULC changes on carbon storage and sequestration were predicted and valued using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model under two future plausible scenarios of business as usual (BAU) and balanced development (BD). According to the results of BAU scenario, continuation of the current trend will lead to a significant reduction in the carbon sequestration and a huge amount of social cost due to the loss of carbon stored in the landscape and its release to the atmosphere. The BD scenario which refers to the principled and under control development of human settlements simultaneously with forest conservational and restoration activities, could potentially reverse the downtrend of carbon sequestration service and avoid future socioeconomic costs, hence add to the economic value of the forest landscape in terms of providing a better sink for carbon storage. The results of this research can facilitate the quantitative and accurate assessment of carbon storage and sequestration relying on more precise biophysical and economic data as well as provide insight for effective land-use planning.


Assuntos
Sequestro de Carbono , Carbono/análise , Mudança Climática , Monitoramento Ambiental/métodos , Solo/química , Biomassa , Florestas , Humanos , Irã (Geográfico)
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