Agro-industrial waste biosorbents of arabica–coffee (WCA) and theobroma–cocoa (WCT) have been characterized and tested to remove Pb(II) from aqueous media. The maximum adsorption capacity of WCA and WCT (qmax = 158.7 and 123.5 mg·g−1, respectively) is comparable or even higher than for several other similar agro-industrial waste biosorbents reported in the literature. Structural and morphological characterization were performed by infrared spectrometry with Fourier transform (FT-IR), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), and charge measurements at the zero point charge (pHPZC). Both biosorbents, WCA and WCT, show cracked surfaces with heterogeneous plates which ones include functional adsorption groups such as OH, C = O and C-O-C. Optimal Pb(II) adsorption occurs for a pH between 4 and 5 at [WCA] and [WCT] dose concentrations of 2 g·L−1. We found that the adsorption process follows pseudo-second order kinetics with a rapid growth rate (almost six times larger for WCA than for WCT), basically controlled by the chemisorption process. The regeneration of both biosorbents was carried out in an eluent of 0.1M HNO3 and they can be efficiently reused up to 5 times.

A new biosorbent based on Nostoc commune (NC) cyanobacteria, chemically modified with NaOH (NCM), has been prepared, characterized and tested as an effective biomass to remove Pb(II) in aqueous media. The adsorption capacity of NCM was determined to be qe = 384.6 mg g−1. It is higher than several other biosorbents reported in the literature. Structural and morphological characterization were performed by FTIR, SEM/EDX and point zero of charge pH (pHPZC) measurements. NCM biosorbent showed more porous surfaces than those NC with heterogeneous plates including functional adsorption groups such as OH, C = O, COO-, COH or NH. Optimal Pb(II) adsorption occurred at pH 4.5 and 5.5 with a biomass dose of 0.5 g L−1. The experimental data of the adsorption process were well fitted with the Freundlich-isotherm model and pseudo-2nd order kinetics, which indicated that Pb(II) adsorption was a chemisorption process on heterogeneous surfaces of NCM. According to the thermodynamic parameters, this process was exothermic (∆H0 < 0), feasible and spontaneous (∆G0 < 0). NCM can be regenerated and efficiently reused up to 4 times (%D > 92%). NCM was also tested to remove Pb (%R~98%) and Ca (%R~64%) from real wastewater.

Descrevemos os resultados do estudo da profundidade ótica do aerossol (POA) e do Forçamento Radiativo Direto (FRD) no topo da atmosfera (TOA), obtidos durante a campanha de medição e monitoramento, XXI Expedição Antártica do Peru, entre os meses de janeiro e fevereiro de 2013, e na área metropolitana de Huancayo (AMH) entre os meses de junho e julho de 2019. Na Estação Antártica Peruana Machu Picchu utilizou-se um fotômetro solar SP02-L. Tal instrumento possui 4 canais: 412 nm, 500 nm, 675 nm e 862 nm, permitindo realizar medições diretas do espectro de radiação visível. Na AMH usamos o sensor BF5, que mede a radiação direta, difusa e global em comprimento de onda curta. Os cálculos de AOD em latitudes polares variaram entre 0,0646 e 0,1061. Na AMH apresenta valor máximo de 0,58 (11 de junho) e mínimo de 0,19 (12 de junho). Determinou-se o coeficiente de Angstrom variando de 0 a 0,07, esses valores indicam a presença de partículas grandes. Na AMH varia de 0 a 1,8, que indica a presença de  aerossóis de fonte de queima de biomassa e industrial. As propriedades óticas observadas foram usadas para estimar a forçante radiativa direta por aerossóis (FRDA) no topo da atmosfera. Os resultados indicam que no King George Island, o FRDA, está entre -2 e 4 W/m2; já para a AMH a forçante radiativa direta de aerossol está entre 0 e 20 W/m2.

Theobroma cacao is the main raw material to produce chocolate, as well as for use in the food, cosmetic, and pharmaceutical industries. However, Moniliophthora roreri is one of the most destructive fungal diseases and the main limiting of cacao production worldwide. Thus, this work aimed to assess the inhibitory effect of extracts of Zingiber officinale (T1) and Aloe vera (T2), and Trichoderma harzianum + Bacillus subtillis. (T3) on Moniliophthora roreri infection in Theobroma cacao; in addition, a control (T4) was also evaluated. Each treatment was applied to six plants of cacao. Incidence of monilia infection and fruit weight were monitored every 15 days (in total four periods) after the application of the treatment by spray. Significant differences (P<0.05) were found among treatments for incidence. It was observed that spraying entire cacao trees after two times (approximately 30 days) showed a reduction of monilia infection. After all periods, T1, T2, and T3 showed an incidence of monilia infection by 20.5, 17.7, and 14.9% respectively, compared to cultural control of 41.1%. This reduction of moniliasis infection translates into an increase in fruit weight average for T3 (8.4 kg), T2 (7.3 kg), and T1 (6.9 kg). In contrast, in the control (T3), the fruit weight average decreased by 5.3 kg. Biological control showed efficient management of pathogens as M. roreri. It is recommended to use such antifungal (Aloe vera) spray over at least 120 days which would decrease infection incidence even more.