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1.
Heliyon ; 9(10): e20606, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37860566

ABSTRACT

Wipe wastes have been used as a cellulosic source to synthesize biochars. Prior to the synthesis of the adsorbents by the pyrolysis of wipes wastes, this waste was treated to remove the pathogenic agents. Then, the wipe wastes were pyrolyzed between 500 and 900 °C to obtain biochars, whose microporosity increased proportionally to the pyrolysis temperature, achieving a maximum CO2-adsorption uptake of 2.53 mmol/g at a pressure of 760 mm of Hg and 25 °C for the biochar pyrolized at 900 °C. The synthesized biochars are also highly selective towards CO2-adsorption in CO2/N2 or CO2/H2 mixtures. Hence, these adsorbents have shown a great potential to be used in flue gas treatment and H2-purification processes. Biochar treatment with KOH further improves microporosity due to chemical activation although the addition of a large amount of KOH leads to excessive microporosity causing a collapse in the pore structure and decreasing CO2-adsorption capacity.

2.
Mar Pollut Bull ; 174: 113299, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35090282

ABSTRACT

The accelerated discard and mismanagement of human-made products are resulting in the continued input of litter into the oceans. Models and field observations show how floating litter can accumulate in remote areas throughout the global ocean, but far less is known about the non-floating litter fraction. Seagrass meadows play an important role in the sediment and natural-debris dynamics, and likely also in the storage and processing of non-floating litter. In this work, non-floating litter was studied across six Posidonia oceanica meadows. Litter accumulated mainly around the landside edge of the meadow. The outer margin of the edge predominantly trapped macro-litter, whilst microplastics accumulated mainly along the inner margin. On average, macro-litter concentrations increased 3-fold after heavy rainfall. Retention of non-floating litter by coastal meadows facilitates the recurrent landward-seaward conveyance of the easily-transportable litter (mainly plastic items) and its fragmentation before it is buried or transferred to deeper areas.


Subject(s)
Alismatales , Plastics , Humans , Oceans and Seas
3.
Chem Commun (Camb) ; 57(60): 7366-7369, 2021 Jul 27.
Article in English | MEDLINE | ID: mdl-34232238

ABSTRACT

POX and NX halogen bonds in combination with π-stacking interactions lead to the sorting of π-extended R- and S-isomers. Theoretical calculations point to a positive synergistic effect between the π-interactions and the halogen bonds to be the origin of such phenomena. As a result, enantiomeric building blocks form homoleptically connected quadrangular structures.

4.
Nat Commun ; 11(1): 6048, 2020 11 27.
Article in English | MEDLINE | ID: mdl-33247160

ABSTRACT

The biological pump transports organic carbon produced by photosynthesis to the meso- and bathypelagic zones, the latter removing carbon from exchanging with the atmosphere over centennial time scales. Organisms living in both zones are supported by a passive flux of particles, and carbon transported to the deep-sea through vertical zooplankton migrations. Here we report globally-coherent positive relationships between zooplankton biomass in the epi-, meso-, and bathypelagic layers and average net primary production (NPP). We do so based on a global assessment of available deep-sea zooplankton biomass data and large-scale estimates of average NPP. The relationships obtained imply that increased NPP leads to enhanced transference of organic carbon to the deep ocean. Estimated remineralization from respiration rates by deep-sea zooplankton requires a minimum supply of 0.44 Pg C y-1 transported into the bathypelagic ocean, comparable to the passive carbon sequestration. We suggest that the global coupling between NPP and bathypelagic zooplankton biomass must be also supported by an active transport mechanism associated to vertical zooplankton migration.


Subject(s)
Biomass , Oceans and Seas , Zooplankton/growth & development , Acoustics , Animals , Carbon/chemistry , Isotope Labeling , Minerals/chemistry
5.
Dalton Trans ; 44(5): 2075-91, 2015 Feb 07.
Article in English | MEDLINE | ID: mdl-25188328

ABSTRACT

Twelve Ir(iii) triscyclometalated compounds containing up to three azobenzene fragments on their structure have been synthesized based on photochromic 2-phenylpyridyl type ligands . These complexes are intended to study the possibility of transferring the photochromicity of the azobenzene fragment to the organometallic compound, and the effect of the substitution pattern, relative distance of the azobenzene to the metal centre, and number of azobenzenes on their properties.

6.
Int J Food Sci Nutr ; 63(7): 843-52, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22524617

ABSTRACT

This study examines the nutritional composition, fatty acid profile and sensory properties of two types of lamb burgers from the Spanish Manchego breed (formula 1 = L: completely from leg lamb meat; formula 2 = LNB with 2/3 leg and 1/3 neck and breast meat). A significant effect of the formulation type was found since Formula 1 had a lower fat percentage (p < 0.001) and higher protein content (p < 0.05). The percentage of total fatty acids and the profile varied for both formulas and consequently their indexes. In addition, the levels of saturated and polyunsaturated fatty acids were slightly lower (p < 0.001) and higher (p < 0.001), respectively, in burgers L than in LNB although both types of burgers raised fatty acid indexes in a healthy threshold. As regarding the sensorial analysis, non-significant differences were described among both formulas. In conclusion, meat quality characteristics were similar for both formulation types being the storage time, the only factor affecting lamb burger stability.


Subject(s)
Fatty Acids/analysis , Food Quality , Meat/analysis , Muscle, Skeletal/chemistry , Animals , Animals, Inbred Strains , Food Storage , Frozen Foods/analysis , Hindlimb , Humans , Models, Chemical , Neck , Nutritive Value , Pectoralis Muscles/chemistry , Principal Component Analysis , Refrigeration , Sensation , Sheep, Domestic , Spain , Water/analysis
7.
Org Biomol Chem ; 8(5): 1000-9, 2010 Mar 07.
Article in English | MEDLINE | ID: mdl-20165789

ABSTRACT

Computational calculations represent a very useful tool to study separately the occurrence of thermal and non-thermal effects of microwave irradiation through the determination of the thermodynamic and kinetic parameters of the reaction. In this paper, we approach the computational study of two previously reported cycloaddition reactions. All of the outcomes indicate the presence of a thermal effect alone for the microwave irradiation that produces changes in the regioselectivity or in the reaction mechanism.

8.
Sci Total Environ ; 337(1-3): 281-6, 2005 Jan 20.
Article in English | MEDLINE | ID: mdl-15626397

ABSTRACT

Ibera wetland is one of the most pristine and singular ecosystems of South America. Satellite-derived thermal analysis of its lacustrine system supported the existence of a groundwater connection with the Yacyreta reservoir through basaltic fractures located along the ancient river bed of the Parana. The groundwater outflow would be located on the geological discontinuity of the eastern border of Ibera wetland, concretely Laguna Ibera and Laguna Luna-Disparo. This new sign of connection comes on top of the hydrological signs which already exist. A call to prudence recommends not extending the recently projected increase of the water level of Yacyreta reservoir. Deeper hydrogeological studies should analyze the hypothesis emerged from this study before modifying the water level of Yacyreta.


Subject(s)
Ecosystem , Geology , Water Supply , Argentina , Conservation of Natural Resources , Fresh Water , Geological Phenomena , Humans , Paraguay
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