Search results for " solution"

Sustainable Recycling of Insoluble Rust Waste for the Synthesis of Iron-Containing Perovskite-Type Catalysts

2019

Insoluble rust waste from the scraping of rusted iron-containing materials represents a cheap, eco-friendly, and available source of iron. LaFeO3 perovskite-type powders were successfully prepared by solution combustion synthesis using rust waste from an electricity transmission tower manufacturer. Solution combustion synthesis enabled introduction of this insoluble iron precursor directly into the final product, bypassing complex extraction procedures. Catalytic activity in the propylene oxidation of the waste-derived LaFeO3 with stoichiometric Fe/La ratio was almost identical to the commercial iron nitrate-derived LaFeO3 , thus demonstrating the viability of this recycling solution. The a…

Study of the Stability of Citrate Capped AgNPs in Several Environmental Water Matrices by Asymmetrical Flow Field Flow Fractionation

2021

Asymmetrical flow field-flow fractionation (AF4) coupled to UV-Vis and dynamic light scattering (DLS) detectors in series, was tested for stability studies of dispersions of citrate-capped silver nanoparticles (AgNPs) in several water matrices. The main goal is to provide knowledge to understand their possible behavior in the environment for short times since mixturing (up to 180 min). Ultrapure (UPW), bottled (BW1, BW2), tap (TW), transitional (TrW) and sea water (SW) matrices were assayed. Observations were compatible with the aggregation of AgNPs, a change in the plasmon band and a size growth with time were done. Fractograms showed different evolution fingerprints in the function of the…

EXISTENCE RESULTS FOR SINGULAR CONVECTIVE ELLIPTIC PROBLEMS

2021

On the scientific work of Victor Isakov

2022

Some recent results on singular $ p $-Laplacian systems

2022

Some recent existence, multiplicity, and uniqueness results for singular p-Laplacian systems either in bounded domains or in the whole space are presented, with a special attention to the case of convective reactions. A extensive bibliography is also provided.

Some recent results on a singular p-laplacian equations

2022

Abstract A short account of some recent existence, multiplicity, and uniqueness results for singular p-Laplacian problems either in bounded domains or in the whole space is performed, with a special attention to the case of convective reactions. An extensive bibliography is also provided.

A fluorescence study of the loading and time stability of doxorubicin in sodium cholate/PEO-PPO-PEO triblock copolymer mixed micelles

2019

Abstract Hypothesis Doxorubicin hydrochloride (DX) is one of the most powerful anticancer agents though its clinical use is impaired by severe undesired side effects. DX encapsulation in nanocarrier systems has been introduced as a mean to reduce its toxicity. Micelles of the nonionic triblock copolymers of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) (PEO-PPO-PEO), are very promising carrier systems. The positive charge of DX confines the drug to the hydrophilic corona region of the micelles. The use of mixed micelles of PEO-PPO-PEO copolymers and a negatively charged bile salt should favour the solubilization of DX in the apolar core region of the micelles. Experiments We st…

Revealing the local structure of CuMo1−xWxO4 solid solutions by multi-edge X-ray absorption spectroscopy

2022

I.P. and A.K. would like to thank the support of the Latvian Council of Science project No. lzp-2019/1-0071. I.P. acknowledges the L’OREAL Baltic “For Women In Science Program” with the support of the Latvian National Commission for UNESCO and the Latvian Academy of Sciences. The experiment at the Elettra synchrotron was performed within project No. 20150303. Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.

Thermodynamic and spectroscopic study of the binding of dimethyltin(IV) by citrate at 25°C

2006

Thermodynamic (potentiometric and calorimetric) and spectroscopic ( 1 H NMR, 119 Sn Mossbauer) studies were performed in aqueous solution in order to characterize the interaction of dimethyltin(IV) cation with citrate ligand. Six species {(CH 3 ) 2 Sn(cit) - ; [(CH 3 ) 2 Sn] 2 (cit) 2 2- ; (CH 3 ) 2 Sn(cit)H 0 ; (CH 3 ) 2 Sn(cit)OH 2- ; [(CH 3 ) 2 Sn] 2 (cit)OH 0 ; [(CH 3 ) 2 Sn] 2 (cit)(OH) 2 - } were found. All the species formed in this system are quite stable and formation percentages are fairly high. For example, at pH = 7.5 and C (CH3)2Sn = C cit = 10 mmol l -1 , E% for [(CH 3 ) 2 Sn] 2 (cit)(OH) 2 - and (CH 3 ) 2 Sn(cit)OH 2- species reaches 65%. Overall thermodynamic parameters obta…

Behind the scenes of artificial intelligence: a study of micro-work platforms in France

2019

Este artículo es una versión resumida del informe “Le Micro-travail en France. Derrière l’automatisation de nouvelles précarités au travail?» This article is a summarized version of the report "Le Micro-travail en France. Derrière l’automatisation de nouvelles précarités au travail?" .; International audience; Micro-work internet services allocate small, standardized tasks of data generation and annotation to crowds of providers. The outputs are mainly used to produce artificial intelligence solutions. It is an exemplary instance of the “platformization” of the economy, and of the transformations of labour that digital technologies bring about. To uncover the conditions under which micro-wo…