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Movement of different strains in Drosophila melanogaster was continuously observed by using computer interfacing techniques and was analyzed by permutation entropy (PE) after exposure to toxic chemicals, toluene (0.1 mg/m³) and formaldehyde (0.01 mg/m³). The PE values based on one-dimensional time series position (vertical) data were variable according to internal constraint (i.e. strains) and accordingly increased in response to external constraint (i.e. chemicals) by reflecting diversity in movement patterns from both normal and intoxicated states. Cross-correlation function revealed temporal associations between the PE values and between the component movement patterns in different chemicals and strains through the period of intoxication. The entropy based on the order of position data could be a useful means for complexity measure in behavioral changes and for monitoring the impact of stressors in environment.

Five kinds of polyimides were synthesized using five dianhydrides (including 2,2-bis[4-(3,4-dicarboxyphenoxy)-phenyl] propane dianhydride (BPADA), 3,3′,4,4′-diphenylsulfone-tetracarboxylic dianhydride (DSDA), 4,4′-(hexafluoroisopropylidene)-diphthalic anhydride (6FDA), 1,4-bis(3,4-dicarboxyphenoxy) benzene dianhydride (HQDPA), and 4,4′-oxydiphthlic dianhydride (ODPA)) and 2,2-bis[4-(4-aminophenoxy)phenyl] hexafluoropropane (BDAF) via the two-step method that included polyaddition to form the polyamic acid and subsequent chemical imidization at ambient temperature. The structures of polyimides were characterized by FTIR and NMR. The thermal properties were characterized by DSC and TGA. All five kinds of polyimides showed good thermal properties and solubility in organic solvents such as DMF, DMAc, NMP and THF at room temperature. The pervaporation (PV) experiments of polyimides for toluene/n-heptane mixture were carried out, and all the polyimides showed selective permeation towards toluene. The fluxes of 6FDA-BDAF, DSDA-BDAF, HQDPA-BDAF and ODPA-BDAF at 80°C were 1.08, 0.96, 1.77 and 0.10 kg·μm/(m²·h), and the separation factors were 5.44, 1.64, 1.28 and 11.44, respectively. The increasing feed temperature resulted in higher flux and lower separation factor of the 6FDA-BDAF membrane.

In this study, electrochemical oxidation of petroleum was performed for the first time. Since petroleum is a rich source of hydrocarbons, its oxidation and electron production resulting in the production of electricity which is green energy is much more efficient than burning it. Electrochemical oxidation of petroleum with Ni-porphyrin-modified graphite electrode in alkaline media and by cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) techniques were investigated. Due to the existence of two aqueous and organic phases, adsorption played a vital role in the process. To further confirm the accuracy of petroleum electrooxidation, electrooxidation of its compounds such as xylene and toluene was performed with the Ni-porphyrin electrode and by the mentioned techniques, which confirmed the previous data.

Nanosized Cu–Mn composite oxide catalysts were prepared from potassium permanganate, copper nitrate, n-butanol, and cetyltrimethylammonium bromide as a manganese source, copper source, reducing agent, and surfactant, respectively. The Cu${}_{0.2}$–Mn sample possessed a small particle size (10–40nm) and a relatively high specific surface area ($46.24{\mathrm{\text{m}}}^2\cdot {\mathrm{\text{g}}}^{-1}$); its main components were Cu${}_{1.5}$Mn${}_{1.5}$O₄ and Mn₃O₄. As a consequence, the Cu${}_{0.2}$–Mn catalyst exhibited good catalytic activity in the oxidation of toluene. At a toluene concentration of 1000ppm and a space velocity of $60,000\mathrm{\text{mL}}\cdot {\mathrm{\text{g}}}^{-1}\cdot {\mathrm{\text{h}}}^{-1}$, the $T_{50}$ and $T_{90}$ of the Cu${}_{0.2}$–Mn catalyst toward toluene were 239${}^{\circ }$C and 250${}^{\circ }$C, respectively. Furthermore, even after 30h of operation at 275${}^{\circ }$C, the conversion of toluene was 99% (at the space velocity of $60,000\mathrm{\text{mL}}\cdot {\mathrm{\text{g}}}^{-1}\cdot {\mathrm{\text{h}}}^{-1}$).

Monoclinic Mn₅O₈, spinel Mn₃O₄, and perovskite Mn ₂O₃were prepared by thermal decomposition of MnC₂O₄. The formation of different MnOx species observed by thermogravimetric analysis (TGA) and X-ray diffraction (XRD) measurements showed temperature-dependent phase transformation following the path of MnC₂O ₄$\to$Mn₅O₈$\to$Mn₃O₄$\to$Mn₂O ₃occurring during the heat treatment process. Among these manganese oxides, the MO-1 (Mn₅O₈ ) showed the best light-driven photothermal catalytic performance reaching up to 99% of toluene degradation and 75% of mineralization efficiencies reached within 30 min. Besides, it is found that structural defects decrease with the increase of the calcinated temperature, and the Mn${}^{4+}$/Mn${}^{3+}$active sites and oxygen vacancies play an important role in improving the light-driven photothermal catalytic performance.

ZIF-8 composites with Mn (Mn-ZIF-8 & Mn/ZIF-8) were prepared by two methods for the complete catalytic oxidation of toluene. The results revealed that catalytic activity increased with the increasing content of manganese, and the activities of the two series composites were different from each other. The Mn${}_{0.8}$-ZIF-8 prepared by the methanol thermal method showed the best catalytic performance, which had the lowest T${}_{90}$ of toluene conversion, compared with the series of Mn/ZIF-8 catalysts. The resulting composites were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), thermogravimetric analysis (TG) and X-ray photoelectron spectroscopy (XPS). It was concluded that Mn, as the active species, might partly replace Zn in the frame of Mn-ZIF-8 for the catalytic oxidation of toluene at lower temperatures.

Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO₂) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO₂ has an important social cost…

This chapter aims to illustrate the research that was conducted in Portugal or in collaboration with Portuguese research groups in the 2011–2022 period on the oxidative conversion of volatile organic compounds (VOCs) to useful building blocks. It concerns the selective oxidation under mild catalytic oxidations of some VOCs (toluene, xylene, ethylbenzene, styrene and n-hexane), which are hazardous to human health and the environment. Both homogeneous and heterogeneous catalysts are discussed.

Studied was the activity of the enzymes involved in the bacterial assimilation of toluene by carbon source limited Acinetobacter sp. grown in titrostat under strictly controlled conditions with specific growth rates ranking from 0.015 to 0.109 h^-1 corresponding to metabolic rates (g toluene assimilated by 1 g cells per hour) from 0.038 to 0.144 h^-1. The study confirms the supposed catabolic pathway of toluene by Acinetobacter sp. via benzoate, benzaldehyde and catechol. The activities of two enzymes of this pathway were found to increase with the rise of microbial growth rate: benzaldehyde dehydrogenase and catechol-2,3-dioxygenase (C23O). Observed was a sharp increase of the specific C23O-activity with the rise of microbial metabolism from nearly maintenance rate, 0.022 h^-1, to 0.046 h^-1 which could be explained with the generally accepted view that the meta pathway catalyzed by C23O provides considerably more energy needed for the activated constructive metabolism of the organism.

Low-temperature (<20°C) anaerobic digestion is an emerging, cost-efficient technology, which has been successfully applied to a variety of high-strength hazardous and non-hazardous waste-streams. Operated at low-temperature, expanded granular sludge bed (EGSB) reactors favour the development of a methanogenic consortium adapted to high biodegradation rates. Reactor operating parameters, such as wastewater characteristics and organic loading rate, affect microbial consortium physiology and therefore could shift bacterial 16S rRNA ratios, for example by changing growth rates and/or physiological activity. Thus, as a screening tool, temporal DGGE-profiling, comparing DNA and cDNA, was employed to highlight the potentially key organisms directly involved in psychrophilic (12°C) toluene methanogenesis in a laboratory-scale EGSB bioreactor. Biomass samples were taken and analysed over a 5-day period, immediately following an imposed increase in toluene loading rate. Functionally active potential toluene-degraders were successfully characterized. The results suggested that a putatively psychrophilic Geobacter-like organism was involved in the process along with hydrogenotrophic Methanospirillum-like and acetotrophic Methanosaeta-like Archaea. The presence of additional mesophilic and thermophilic putative toluene-degraders suggested, however, that reactor operating temperature may not have been the main factor for the development of this well-established and active microbial methanogenic consortium.