Search results for "i.i.d."
showing 10 items of 4310 documents
Kadmiumaltistuksen havaitseminen Hydropsyche pellucidula -vesiperhostoukilla (Trichoptera: Hydropsychidae) hyperspektrikuvantamisen ja kidusvaurioide…
2017
Metallipäästöt aiheuttavat vesistöissä eliöyhteisöille monenlaisia haittavaikutuksia, joita voidaan tutkia bioindikaattori- eli ilmentäjälajimenetelmin. Vesiperhostoukkia (Trichoptera) on käytetty virtavesien metallisaastumisen indikaattoreina, sillä ne kestävät metallialtistusta suhteellisen hyvin, mutta altistuksen seurauksena toukilla voi esiintyä morfologisia muutoksia, kuten kidusvaurioita tai pintakudoksen tummumista. Koska toisaalta vierasaineiden kudospitoisuusmittaus on usein työlästä ja toisaalta rakenteellisten muutosten arviointi altis subjektiiviselle harhalle, tavoitteenani oli kehittää objektiivinen ja kustannustehokas tapa selvittää metallialtistusta ja sen vaikutuksia pohja…
AN INTEGRATED APPROACH FOR THE HCl AND METALS RECOVERY FROM WASTE PICKLING SOLUTIONS: PILOT PLANT DESIGN AND OPERATIONS
2020
Pickling is one of the key steps in the hot-dip galvanizing process, where HCl solutions are largely used to remove metal oxides from metallic surfaces, thus generating spent waste liquors containing high concentrations of metals and acid. Disposal of the industrial pickling waste dramatically affects the hot-dip galvanizing industry economics and environmental footprint. Thus, reducing strong acid waste disposal is one of the most beneficial steps to enhance the process sustainability. Moreover, the continuous regeneration of pickling solutions enhances pickling rate and process performance, also minimizing industrial wastewater disposal and chemicals consumption promoting the circular use…
NONEQUILIBRIUM PHENOMENA AND METASTABILITY IN MESOSCOPIC AND QUANTUM SYSTEMS
2020
Here we summarize some relevant results related to nonequilibrium phenomena in mesoscopic and quantum systems. A common phenomenon in the dynamics of out-of-equilibrium systems is the metastability, and the problem of the lifetime of metastable states involves fundamental aspects of nonequilibrium statistical mechanics. Metastability (see Fig. 1) is a signature of a first order phase transition, often characterized by a long-living metastable state. In particular, the stability of a metastable state can be enhanced by Gaussian and non-Gaussian noise sources. This counterintuitive effect has been found in different physical areas, ranging from spintronics, aggregation kinetics of Brownian pa…
Manipulating Light with Tunable Nanoantennas and Metasurfaces
2022
The extensive progress in nanofabrication techniques enabled innovative methods for molding light at the nanoscale. Subwavelength structured optical elements and, in general, metasurfaces and metamaterials achieved promising results in several research areas, such as holography, microscopy, sensing and nonlinear optics. Still, a demanding challenge is represented by the development of innovative devices with reconfigurable optical properties. Here, we review recent achievements in the field of tunable metasurface. After a brief general introduction about metasurfaces, we will discuss two different mechanisms to implement tunable properties of optical elements at the nanoscale. In particular…
Bidentate [N, N] nickel complexes with salen type ligands for polymerization of methyl methacrylate
2008
Otrzymano kompleksy niklu [N,N]NiBr2, które po aktywacji związkiem glinoorganicznym zastosowano w polimeryzacji metakrylanu metylu (MMA). Dwukleszczowe ligandy [N,N] uzyskano zastępując w ligandach salenowych grupy hydroksylowe podstawione do pierścieni fenylowych różnymi grupami alkoksylowymi (OMe lub OCH2C6H5). Metyloalumoksan (MAO) okazał się skutecznym aktywatorem kompleksów niklu w polimeryzacji MMA. Same kompleksy bez aktywatora nie wykazywały żadnej aktywności. Stwierdzono, że aktywność badanych układów katalitycznych rośnie ze wzrostem stosunku molowego Al/Ni. W wyniku polimeryzacji w stosowanych warunkach otrzymano poli(metakrylan metylu) (PMMA) z przewagą triad syndiotaktycznych c…
Matrix sustainability : applying input-output analysis to environmental and economic sustainability indicators : case: Finnish Forest Sector
2004
Pre-requisite for all sustainability actions in business is accurate measurement of economic, environmental and social performance. Sustainability indicators, or indicator sets, are then the tools, which simplify the complex sustainability information applicable for management processes, decision-making and communication. Measuring business sustainability is not an easy task, especially while simultaneously considering macro-level sustainability. Indicators should somehow capture the corporate/ industry contributions to sustainability and increase the understanding on the link between business performance and macro-level concerns. Hence, traditional macro-level tools from the field of econo…
IL PAGAMENTO “NECESSARIAMENTE INTERMEDIATO” DELL’OBBLIGAZIONE PECUNIARIA NELLA LEGISLAZIONE DI DERIVAZIONE EUROPEA: VERSO IL SUPERAMENTO DELL’UNICITÀ…
2015
Il lavoro muove dall’idea di analizzare il sistema delle regole che definiscono, sul piano dell’an, del quando e del quomodo, l’esattezza dell’adempimento che può definirsi (necessariamente) intermediato dell’obbligazione pecuniaria: nella vicenda solutoria della quale, cioè, risulti indefettibile, per volontà della legge o per scelta dei privati, l’interposizione di uno o più soggetti, altri rispetto al debitore e al creditore parti originarie del rapporto obbligatorio, con funzioni ausiliarie. Ciò al fine di saggiare la bontà della ipotesi ricostruttiva in base alla quale l’adempimento dell’obbligazione pecuniaria per mezzo di operazioni di pagamento intermediato non sia governato dalla l…
Catalytic Conversion of Glucose and Chlorella sp. into Furans in the Presence of Niobium Oxide
2023
A series of Nb2O5 solid catalysts have been prepared to be used for the catalytic dehydration of glucose and sugars from algae Chlorella sp. into added value furans. The glucose transformation gave rise to 5-hydroxymethylfurfural (5-HMF). Chlorella sp. was used in the same catalytic conditions to be valorised to furans. By preliminary studies we concluded that the algae aqueous suspension needed a previous treatment in the presence of SiO2 pellets to liberate the carbohydrates that in the catalytic reaction in the presence of Nb2O5 materials gave rise 5-HMF and furfural. The best operative conditions and Nb2O5 catalysts were individuated. The most performant Nb2O5 catalyst also showed an ex…
Determination of metal concentrations in certified plastic reference materials after small-size autoclave and microwave-assisted digestion followed w…
2017
Abstract The digestion methods for the determination of As, Cd, Cr, Pb, Sb, Sn and Zn concentrations in plastic samples using microwave-assisted digestion (MW-AD) and small-size autoclave digestion was developed. The certified polyethylene, polypropylene, polyvinyl chloride and acrylonitrile butadiene styrene certified reference materials were used in order to find digestion method working properly for several sample matrices. Efficiency of the digestion methods was evaluated by analyzing the residual carbon in digests by TOC analyzer. MW-AD using a mixture of 7 mL of HNO 3 and 3 mL of H 2 O 2 as a digestion solution resulted in excellent recoveries for As, Cd, Pb, Sb and Zn, and were in th…
Vecāka pirmsskolas vecuma bērnu pozitīvās attieksmes veicināšana pret vienaudžiem
2018
Kvalifikācijas darbs izstrādāts par tēmu „Vecāka pirmsskolas vecuma bērnu pozitīvās attieksmes veicināšana pret vienaudžiem”. Darba autore: Jekaterina Romanova Darba vadītāja: Asof.prof. Dr. Psyh. Valentīna Romenkova Kvalifikācijas darba mērķis ir noteikt paņēmienus, kas veicina bērnu pozitīvo attieksmi pret vienaudžiem. Kvalifikācijas darbs sastāv no divām daļām. Teorētiskajā daļā analizētas pedagoģijas un psiholoģijas zinātnieku atziņas par mijiedarbības procesu, raksturots bērnu 5-6 gadu vecums. Tāpat darba teorētiskajā daļā tika analizētas iespējas veicināt bērnu pozitīvās attieksmes pret vienaudžiem. Bērnu pozitīvā attieksme pret vienaudžiem vecākajā pirmsskolas vecumā veidojas no labv…