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A nanocrystalline TiO2 glass coating was developed by sintering sol–gel derived thin film at 450°C. FTIR spectroscopy confirmed the absence of hydroxide gel and unreacted precursor as well as the presence of TiO2. The crystalline phase was predominantly anatase as identified from the XRD measurement and the crystallite size obtained from Scherrer's equation was 166 nm. This was in good agreement with the TiO2 nanoparticle size of 148 nm obtained from BET adsorption experiment. The approximate BET surface coverage was 10.38 m2 g−1 and the total pore volume was 0.02 cc g−1. Most importantly, the sintered TiO2 coated quartz glass showed a significant increase of 27.8% in UV reflectance, as obtained from UV-vis measurement and subsequent Kubelka–Munk function. This result is particularly advantageous to prevent bird-strike against high-rise glass buildings and windows. [ABSTRACT FROM AUTHOR]

This mini review covers a brief overview of three generations of solar cells, definition of major photovoltaic (PV) parameters, mechanisms, advantages and limitations of different types of solar cells such as multijunction, thin film, quantum dot, dye sensitized and perovskite solar cells, and what role the earth abundant selenium can play in each type of solar cells, followed by a comparative study of the benefits and challenges that selenium can offer in terms of PV properties, as well as the major players and cost analysis in this arena. As far as PV properties are concerned, BaZr(S0.6Se0.4)3 distorted chalcogenide perovskite solar cell can possibly lead the future, the next best ones being AlGaInP multijunction solar cell with Se emitter dopant and Se electrolyte additive in Zn-Cu-In-Se QD-sensitized solar cell. Cost-wise perovskite cell holds a lot of promise, but the efficacy of selenium needs to be explored further. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

• Silica nanoplate structure is being reported for the first time in sol-gel coating. • Nanopores created by oxalic acid catalyst and gaps in between nanoplates increases light transmittance by 7%. • Carboxymethyl cellulose nanofiber imparts stability and hydrophobicity in glass coating. • The resultant coating is completely scratch resistant. • The formulation is eco-friendly and devoid of conventional hazardous components. This paper reports an acid catalyzed sol-gel formulation with tetraethyl orthosilicate (TEOS) as a precursor for developing nano-porous anti-reflective coating on glass. The novelty of this formulation lies in judicious choice of ingredients. Oxalic acid, an unconventional acid catalyst created nano-pores of average diameter 1.25 μm due to entrapped carbon dioxide, which in turn increased the light transmittance by 7.01%. Carboxymethyl cellulose, a biopolymer fiber of 221 nm diameter imparted stability as well as hydrophobicity, without the need for high temperature annealing and hazardous trimethylchlorosilane (TMCS) treatment respectively. The fibrous stabilizer formed a top layer over two or three stacked silica nanoplates. The nanoplates had an average thickness 537 nm and inter-plate gaps of 119 nm, which also increased anti-reflectance property. The hardest pencil 9H failed to make any scratches on this coating, proving complete scratch-resistance. The invented formulation is eco-friendly and similar to solar cell technology. [ABSTRACT FROM AUTHOR]

Highlights: [•] We measured bumblebee nectar imbibition rate in a laboratory setting. [•] Our artificial nectars varied in sugar concentration (C) and sugar composition (O). [•] Bumblebee imbibition rate (I) increases linearly with C up to 27%. [•] Over 27%, I starts to decrease, and is influenced by C, viscosity (η) and O. [•] Energy intake rate (E) is maximized at 42–56%, and is influenced by C, η and O. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]