Search results for "Lead"

Applications in nanophotonics of lead halide perovskite nanocrystals

2021

Physical - chemical interaction of injection waters with depleted gas formations

2021

In order that the physical - chemical interaction of the injection water with the porous-permeable or fissured medium of reservoirs do not lead to their degradation, it is necessary that the waters to meet a number of quality conditions. The treatment and conditioning of the injectable waters is imperative to do so due to the fact that their provenance is different, such as reservoir waters, wastewater resulting from various operations – petroleum operations, meteoric waters, etc. and, in particular, due to the very large volumes of injected water. Failure to follow the steps associated with the water treatment process inevitably leads to premature reduction of the injection wells receptivi…

Detection of archaeological forgeries of Iberian lead plates using nanoelectrochemical techniques. The lot of fake plates from Bugarra (Spain)

2014

Identification of forgeries is of considerable interest in studies of archaeological signariums and written Iberian artifacts, elements of capital importance for the knowledge of that culture, because there are many Iberian inscribed lead plate counterfeits circulating in the market and among many museum funds. A case study of identification of forgeries of archaeological lead using voltammetry of microparticles (VMP) and scanning electrochemical microscopy (SECM), aided by conventional optical microscopy and scanning electron microscopy (SEM/EDX) is described. The electrochemical methods are essentially non-invasive so can be applied to samples of nanoscopic size. Application to the authen…

The Diagnosis of Disease by Element Analysis

1988

The elemental composition of the human body images in principle the elements of the periodic system. In the literature, about 80 elements are reported to occur in the human body and the number is expected to increase by the introduction of methods more sensitive in detection. The elemental composition in reference man as published (1) is summarized in tab. 1. From the major elements in reference man, the determination of the elements nitrogen, calcium, phosphorus, potassium, sodium, chlorine and magnesium are of importance for the diagnosis of diseases. The importance of the element determination for the diagnosis of diseases is also documented by the numbers of element determinations done …

Use of lead isotopic fingerprint in human scalp hair to identify potential sources of pollution in industrial Sicilian sites (Italy)

2019

Petrochemical industries represent a controversial, although important, the economic resource. They offer numerous job opportunities, which in turn contribute to the economic development of the city. People living in towns close to industrial plants are particularly exposed to severe environmental decline, which involves the deterioration of the quality of air, water, soil, and food. The municipalities of Augusta (SR), Gela (CL) and Pace del Mela (ME) host large oil refineries, together with several important chemical and petrochemical industries. The main goal of this study is to evaluate if stable lead isotope ratios measured in the biological matrix can be used as pollution fingerprints.…

Lead optimization of pyrazolo[1,2-a]-benzo-[1,2,3,4]-tetrazin-3-one nucleus to increase the biological properties as anticancer compounds

Raman spectroscopic study of some lead phosphate glasses with tungsten ions

2006

Abstract The structure of x WO 3  · (100 −  x )[2P 2 O 5  · PbO] glass system with 0 ⩽  x  ⩽ 50 mol% was investigated by Raman spectroscopy. The characteristic bands of these glasses due to the stretching and bending vibrations were identified and analyzed by the increasing of WO 3 content. This fact allowed us to identify the specific structural units which appear in these glasses and thus to point out the network modifier role of tungsten oxide for low concentrations and its former role at high concentrations.

Electrochemical identification of painters/workshops: The case of Valencian Renaissance-Baroque painters (ca. 1550- ca. 1670)

2019

[EN] The voltammetry of immobilized particles (VIMP) methodology was applied to discriminate the oil painting production of a series of seven painters/workshops that worked in Valencia (Spain) between ca. 1530 and ca. 1650. When submicrosamples used for cross-section FESEM/EDX analysis were attached to graphite electrodes in contact with aqueous acetate buffer, well-defined responses were obtained. The reductive processes of lead pigments (lead white and lead-tin yellow) overlapped those associated to the lead soaps and other species resulting from the pigment-oil binder interaction in the sample. Such responses, which are theoretically modeled, were sensitive to changes in paint type and d…

Nozīmes veidošana lietišķajos rakstos

2017

Šajā pētījumā analizēta nozīmes veidošana laikraksta ‘The Economist’ ievadrakstu virsrakstos, apakšvirsrakstos un ievados, kā arī laikraksta ‘The Financial Times’ titulrakstu virsrakstos un apakšvirsrakstos. Pētījuma mērķis bija analizēt nozīmes veidošanu, pētot teikumu un vārdkopu aspektu, situācijas veidu un funkcionālo koherenci. Lai to sasniegtu, tika analizēti 15 laikraksta ‘The Economist’ rakstu virsraksti, apakšvirsraksti un ievadi, kā arī 13 laikraksta ‘The Financial Times’ rakstu virsraksti un apakšvirsraksti. Izmantojot Komrija (1976), Smitas (1991) un Van Dijka (1988) atziņas, pētījumā secināts, ka laikraksta ‘The Economist’ rakstu pirmie elementi ir savstarpēji saistīti ar funkc…

Nanostructured lead-acid negative electrode with reduced graphene oxide

2021

Aim of this work is to develop a new nano-structured and nano-composite lead acid negative electrode with reduced graphene oxide (rGO). Nanostructured electrodes are fabricated by template electrodeposition of lead nanowires on a lead current collector. A polycarbonate track-etched membrane was used as a template (200 nm mean pores diameter). rGO was deposited on the nanostructured electrode from a graphene oxide (GO) dispersion in acetate buffer solution (ABS) (0.2 g/L). Potentiostatic deposition of rGO at -0.8 V vs. standard calomel electrode (SCE) was performed. Electrode with rGO was tested as negative electrode in cell with 5M sulfuric acid solution, a commercial pasted positive plate,…