SEM-EDX and FTIR analysis of archaeological ceramic potteries from southern Italy.

Sherds of ancient ceramics potteries, dating back to the seventh century BC and excavated from southern Italy, were analyzed in terms of microstructure and porosity (SEM), elemental composition (EDX), chemical bonding and mineralogical components (FTIR) in order to establish correlation with firing temperature, firing condition and provenance. Si/Al ratio from EDX analysis showed three major categories of raw materials (illite/montmorillonite, kaolinite and mullite), suggesting difference in provenance. Uniformly sized silica nanoparticle (0.7 µm diameter) and trace amount of silver are being reported for the first time in one sample. Anorthite mineral and quartz inclusion was detected by FTIR in certain samples. All samples showed a prominent band for Si-O stretching, which shifted from 1062 cm-1, broadened and appeared as doublet, relative to processing temperature. FTIR results proved incomplete dihydroxylation and undissociated carbonate in three samples, indicating a firing temperature of 700-800°C, whereas other samples were fired above 900°C. Only one sample among these three showed bloating pores in between interconnecting glassy matrix in SEM image, indicating a firing temperature of 1100-1200°C. The absence of magnetite along with significant Fe and Mn content indicated the formation of jacobsite, an iron manganese spinel complex, MnFe2O4, which is responsible for the black gloss effect in two particular samples and can be further confirmed by XRD. The presence of numerous small pores in SEM image of one of these two samples (1.2 µm diameter) was indicative of extended vitrification at higher temperature than the other one. However, magnetite was responsible for black gloss effect in two other samples, proving difference in provenance. Therefore, SEM-EDX and FTIR results can offer valuable insight into the firing conditions, gloss decoration and provenance of ancient ceramic potteries.

Tobacco Cost of Illness Studies: A Systematic Review.

INTRODUCTION: To identify studies reporting costs arising from tobacco use and detail their (1) economic approaches, (2) health outcomes, and (3) other cost areas included. METHODS: We searched PubMed, Scopus, Cochrane Library, EconLit, and Google Scholar for studies published between 2008 and April 2018 in English. Eligible articles reported tobacco-related costs and included all tobacco-using populations (multinational, national, subpopulations, and involuntary smokers). All economic approaches that resulted in monetary outcomes were included. We reported USD or converted local currencies to USD. Two health economists extracted and two researchers independently reviewed the data. RESULTS: From 4083 articles, we reviewed 361 abstracts and examined 79 full-texts, with 63 (1.6%) deemed eligible. There were three multinational, thirty-four national, twenty-one subpopulation or condition(s)-specific analyses, and five evaluating involuntary smoking. The diverse approaches and outcomes precluded integrating costs, but these were substantial in all studies. For instance, about USD 1436 billion in global health expenditures and productivity losses in 2012 and USD 9 billion in lost productivity in China, Brazil, and South Africa in 2012. At the national level, costs ranged from USD 4665 in annual per respondent health expenses (Germany 2006-2008) to USD 289-332.5 billion in medical expenses (United States 1964-2014). CONCLUSIONS: Despite wide variations in the methods used, the identified costs of tobacco are substantial. Studies on tobacco cost-of-illness use diverse methods and hence produce data that are not readily comparable across populations, time, and studies, precluding a consistent evidence-base for action and measurement of progress. Recommendations are made to improve comparability. IMPLICATIONS: In addition to the health and financial costs to individual smokers, smoking imposes costs on the broader community. Production of comparable estimates of the societal cost of tobacco use is impaired by a plethora of economic models and inconsistently included costs and conditions. These inconsistencies also cause difficulties in comparing relative impacts caused by differing factors. The review systematically documents the post-2007 literature on tobacco cost-of-illness estimations and details conditions and costs included. We hope this will encourage replication of models across settings to provide more consistent data, able to be integrated across populations, over time, and across risk factors.

Cheap non-toxic non-corrosive method of glass cleaning evaluated by contact angle, AFM, and SEM-EDX measurements.

Glass surface cleaning is the very first step in advanced coating deposition and it also finds use in conserving museum objects. However, most of the wet chemical methods of glass cleaning use toxic and corrosive chemicals like concentrated sulfuric acid (H2SO4), piranha (a mixture of concentrated sulfuric acid and 30% hydrogen peroxide), and hydrogen fluoride (HF). On the other hand, most of the dry cleaning techniques like UV-ozone, plasma, and laser treatment require costly instruments. In this report, five eco-friendly wet chemical methods of glass cleaning were evaluated in terms of contact angle (measured by optical tensiometer), nano-scale surface roughness (measured by atomic force microscopy or AFM), and elemental composition (measured by energy dispersive x-ray spectroscopy or SEM-EDX). These glass cleaning methods are devoid of harsh chemicals and costly equipment, hence can be applied in situ in close proximity with plantation such as greenhouse or upon subtle objects such as museum artifacts. Out of these five methods, three methods are based on the chemical principle of chelation. It was found that the citric acid cleaning method gave the greatest change in contact angle within the hydrophilic regime (14.25° for new glass) indicating effective cleansing and the least surface roughness (0.178 nm for new glass) indicating no corrosive effect. One of the glass sample showed unique features which were traced backed to the history of the glass usage.

Photocatalytic degradation of methylene blue dye by zinc oxide nanoparticles obtained from precipitation and sol-gel methods.

Zinc oxide (ZnO) nanoparticles were synthesized by precipitation and sol-gel methods. The aim of this study was to understand how different synthetic methods can affect the photocatalytic activity of ZnO nanoparticles. As-synthesized ZnO nanoparticles were characterized by X-ray diffraction (XRD) and UV-Visible spectroscopic techniques. XRD patterns of ZnO powders synthesized by precipitation and sol-gel methods revealed their hexagonal wurtzite structure with crystallite sizes of 30 and 28 nm, respectively. Their photocatalytic activities were evaluated by photocatalytic degradation of methylene blue, a common water pollutant, under UV radiation. The effects of operational parameters such as photocatalyst load and initial concentration of the dye on photocatalytic degradation of methylene blue were investigated. While the degradation of dye decreased over the studied dye concentration range of 20 to 100 mg/L, an optimum photocatalyst load of 250 mg/L was needed to achieve dye degradation as high as 81 and 92.5 % for ZnO prepared by precipitation and sol-gel methods, respectively. Assuming pseudo first-order reaction kinetics, this corresponded to rate constants of 8.4 × 10-3 and 12.4 × 10-3 min-1, respectively. Hence, sol-gel method is preferred over precipitation method in order to achieve higher photocatalytic activity of ZnO nanostructures. Photocatalytic activity is further augmented by better choice of capping ligand for colloidal stabilization, starch being more effective than polyethylene glycol (PEG).

The effect of sugar solution type, sugar concentration and viscosity on the imbibition and energy intake rate of bumblebees.

Nectar is an essential resource for bumblebees and many other flower-visiting insects. The main constituents of nectar are sugars, which vary in both composition and concentration between plant species. We assessed the influence of sugar concentration, sugar solution viscosity and sugar solution composition on the imbibition and energy intake rate of bumblebees, Bombus impatiens Cresson (Hymenoptera: Apidae). To do this, we measured their rate of solution intake for 49 different sugar solution treatments, which varied in both sugar composition and concentration. In general, the imbibition rates of bumblebees were found to increase with increasing sugar concentration, probably due to their preference for high sugar concentrations, up to a concentration of 27% (w/w), at which point solutions reached a threshold viscosity of approximately 1.5-1.6 mPa.s. Above this threshold, the increasing viscosity of the solutions physically inhibited the imbibition rates of bees, and imbibition rate began to decrease as the concentration increased. Nevertheless, bumblebee energy intake rate increased with increasing concentration up to about 42-56%. Although we found that sugar solution composition had an impact on both imbibition and energy intake rate, its effect was not as straightforward as that of sugar concentration and viscosity.

Polymer-coated magnetic nanoparticles: surface modification and end-functionalization.

ATRP (atom transfer radical polymerization) approach was employed to synthesis polymer-coated magnetite nanoparticles. These particles had an average diameter of 7.1 nm and a narrow size distribution. Characterization was performed using various techniques like Transmission Electron Microscopy (TEM), Ultraviolet-Visible spectroscopy (UV-vis), Fourier Transform Infrared spectroscopy (FTIR), Atomic Force Microscopy (AFM), and Vibrating Sample Magnetometry (VSM). The challenge was to obtain a thin shell and discrete particles in an unagglomerated state. Several factors like presence/choice of solvent, monomer-to-initiator concentration and structure of initiator were found to play a key role in this study. Attempts have been made to tailor the polymer shells by end-functionalization. This work has an enormous biomedical application potential.