Intra-laboratory assessment of a method for the detection of TiO2 nanoparticles present in sunscreens based on multi-detector asymmetrical flow field-flow fractionation

In this study, an intra-laboratory assessment was carried out to establish the effectiveness of a method for the detection of TiO2 engineered nanoparticles (ENPs) present in sunscreen containing nano-scale TiO2 and a higher nanometer-range (approx. 200-500 nm) Ti02, as well as iron oxide particles. Three replicate measurements were performed on five separate days to generate the measurement uncertainties associated with the quantitative asymmetrical flow field-flow fractionation (AF4) measurement of the hydrodynamic radius r(h, mode1) (MALS), rh,,odei (ICP-MS), r(h, mode2) (ICP-MS), and calculated mass-based particle size distribution (d(10), d(50), d(90)). The validation study demonstrates that the analysis of TiO2 ENPs present in sunscreen by AF4 separation-multi detection produces quantitative data (mass-based particle size distribution) after applying the sample preparation method developed within the NanoDefine project with uncertainties based on the precision (u(IP)) of 3.9-8.8%. This method can, therefore, be considered as the method with a good precision. Finally, the bias data shows that the trueness of the method (u(t) = 5.5-52%) can only be taken as a proxy due to the lack of a sunscreen standard containing certified TiO2 ENPs

Monitoring the injection of microscale zerovalent iron particles for groundwater remediation by means of complex electrical conductivity imaging

The injection of microscale zerovalent iron (mZVI) particles for groundwater remediation has received much interest in recent years. However, to date, monitoring of mZVI particle injection is based on chemical analysis of groundwater and soil samples and thus might be limited in its spatiotemporal resolution. To overcome this deficiency, in this study, we investigate the application of complex electrical conductivity imaging, a geophysical method, to monitor the high-pressure injection of mZVI in a field-scale application. The resulting electrical images revealed an increase in the induced electrical polarization (∼20%), upon delivery of ZVI into the targeted area, due to the accumulation of metallic surfaces at which the polarization takes place. Furthermore, larger changes (>50%) occurred in shallow sediments, a few meters away from the injection, suggesting the migration of particles through preferential flowpaths. Correlation of the electrical response and geochemical data, in particular the analysis of recovered cores from drilling after the injection, confirmed the migration of particles (and stabilizing solution) to shallow areas through fractures formed during the injection. Hence, our results demonstrate the suitability of the complex conductivity imaging method to monitor the transport of mZVI during subsurface amendment in quasi real-time

Istorijat gajenja krompira u Crnoj Gori

The beginning of potato growing is associated to Incas. This ancient civilization cultivated potatoes of all shapes, colours and flavours 10,000 years ago in the Andes. For communities that lived in the Andes at that time, these plants were the most important source of food. For the rest of the world, until the XVI century, potato was unknown culture. Spanish conqueror Pizarro brought potatoes from South America to Europe in 1562. As a botanical curiosity, first potatoes arrived to Spain, and were later on spread to other countries of Europe. For many years after introduction, potato was grown as an ornamental plant, until the Europeans accepted it as an edible plant. Growing of potatoes in Montenegro begins in late eighteenth century, similar as in other Balkan countries. Bishop Petar I Petrović Njegoš brought potatoes in Montenegro probably in early 1786. Due to favourable climatic and soil conditions, the areas planted with potatoes were quickly spread in Montenegro. Expansion of the areas planted with potatoes significantly improved the life of local population, and this culture, due to its enormous importance as a food, quickly got the epithet of “life-saving food”. Therefore, potatoes became, for a very short time, the leading agricultural crop and this status is maintained up to the present day.Početak gajenja krompira vezuje se za Inke. Ova drevna civilizacija je prije 10.000 godina, na Andima, gajila krompir svih oblika, boja i ukusa. Za zajednice koje su u to vrijeme živjele na Andima ova biljna vrsta je bila najznačajniji izvor hrane. Za ostatak svijeta, sve do XVI vijeka, krompir je bio nepoznata kultura. Iz Južne Amerike u Evropu krompir je donio španski osvajač Pizarro 1562. godine. Kao botanički kuriozitet krompir je prvo stigao u Španiju, a odatle se kasnije proširio i u ostale zemlje Evrope. Godinama nakon unošenja krompir je gajen kao ukrasna biljka, sve dok ga Evropljani nijesu prihvatili kao jestivu namirnicu. Gajenje krompira u Crnoj Gori počinje krajem XVIII vijeka, manje-više kao i u ostalim balkanskim državama. Krompir je u Crnu Goru donio vladika Petar I Petrović Njegoš, najvjerovatnije početkom 1786. godine. Zahvaljujući veoma povoljnim klimatskim i zemljišnim uslovima površine pod krompirom u Crnoj Gori su se brzo širile. Širenjem površina pod krompirom značajno je poboljšan život lokalnog stanovništva, pa je ova kultura, zbog svog ogromnog prehrambenog značaja, vrlo brzo dobila epitet spasonosne hrane. Zbog toga je krompir, za veoma kratko vrijeme, postao vodeća poljoprivredna kultura, a taj status je zadržao i do današnjih dana

Characterization of gold nanorods conjugated with synthetic glycopolymers using an analytical approach based on spICP-SFMS and EAF4-MALS

A new comprehensive analytical approach based on single-particle inductively coupled plasma-sector field mass spectrometry (spICP-SFMS) and electrical asymmetric-flow field-flow-fractionation combined with multi-angle light scattering detection (EAF4-MALS) has been examined for the characterization of galactosamine-terminated poly(N-hydroxyethyl acrylamide)-coated gold nanorods (GNRs) in two different degrees of polymerization (DP) by tuning the feed ratio (short: DP 35; long: DP 60). spICP-SFMS provided information on the particle number concentration, size and size distribution of the GNRs, and was found to be useful as an orthogonal method for fast characterization of GNRs. Glycoconjugated GNRs were separated and characterized via EAF4-MALS in terms of their size and charge and compared to the bare GNRs. In contrast to spICP-SFMS, EAF4-MALS was also able of providing an estimate of the thickness of the glycopolymer coating on the GNRs surface

A large-scale 3D study on transport of humic acid-coated goethite nanoparticles for aquifer remediation

Humic acid-coated goethite nanoparticles (HA-GoeNPs) have been recently proposed as an effective reagent for the in situ nanoremediation of contaminated aquifers. However, the effective dosage of these particles has been studied only at laboratory scale to date. This study investigates the possibility of using HA-GoeNPs in remediation of real field sites by mimicking the injection and transport of HA-GoeNPs under realistic conditions. To this purpose, a three-dimensional (3D) transport experiment was conducted in a large-scale container representing a heterogeneous unconfined aquifer. Monitoring data, including particle size distribution, total iron (Fetot) content and turbidity measurements, revealed a good subsurface mobility of the HA-GoeNP suspension, especially within the higher permeability zones. A radius of influence of 2 m was achieved, proving that HA-GoeNPs delivery is feasible for aquifer restoration. A flow and transport model of the container was built using the numerical code Micro and Nanoparticle transport Model in 3D geometries (MNM3D) to predict the particle behavior during the experiment. The agreement between modeling and experimental results validated the capability of the model to reproduce the HA-GoeNP transport in a 3D heterogeneous aquifer. Such result confirms MNM3D as a valuable tool to support the design of field-scale applications of goethite-based nanoremediation.Seventh Framework Programm

COST Action PRIORITY: An EU Perspective on Micro- and Nanoplastics as Global Issues

Plastic fragments, weathered into or released in the form of micro- and nanoplastics, are persistent and widespread in the environment, and it is anticipated that they have negative environmental impacts. This necessitates immediate efforts for management strategies throughout the entire plastics lifecycle. This opinion paper was initiated by the EU COST Action CA20101 PRIORITY, which focuses on the need to develop an effective global networking platform dealing with research, implementation, and consolidation of ways to address the worldwide challenges associated with micro- and nanoplastics pollution in the environment