40 research outputs found
A bibliometric description of lignin applicability for the removal of chemical pollutants in effluents
Several industrial sectors produce tons of effluents daily containing a high amount of hazardous chemical pollutants that pose a major threat to the environment and human health. Current wastewater treatment methods, such as flocculation and activated carbon adsorption, have drawbacks linked to high material cost and too much energy consumption. Thus, the search for renewable, biodegradable, and efficient materials has been the object of research aimed at replacing the conventional materials used to cheapen processes and reduce environmental impacts. Lignin stands out in this context as it has low cost and high availability. Therefore, several scientific researches were developed to harness the potential of lignin, especially as adsorbent, for the removal of chemical agents from effluents. This paper presents a bibliometric review performed on the Scopus database, showing the evolution of studies related to the applicability of lignin in the removal of chemical pollutants in waters over the last five years. Data regarding annual publications, languages, journals, countries, institutions, keywords, and subjects were analyzed. The realized screening selected 130 articles that met the previously defined criteria. Results indicated a strong collaboration between countries and China's substantial contribution to the documents. The analysis also has shown that lignin is mainly used as adsorbent material, sorbent, flocculant agent, and hydrogel and presents important results and information for future researchers on this topic.The authors acknowledge financial assistance from the Brazilian research funding agencies such as CAPES
(Coordination for the Improvement of Higher Education Personnel) under Finance Code 001, a Brazilian foundation within the Ministry of Education (MEC), CNPq (National Council for Scientific and Technological Development), a Brazilian foundation associated to the Ministry of Science and Technology (MCT), and
FAPITEC/SE (the Foundation of Support to Research and Technological Innovation of the State of Sergipe).info:eu-repo/semantics/publishedVersio
Reproductive outcomes after non-occupational exposure to hexavalent chromium, Willits California, 1983-2014
Evidence for bystander signalling between human trophoblast cells and human embryonic stem cells
Maternal exposure during pregnancy to toxins can occasionally lead to miscarriage and
malformation. It is currently thought that toxins pass through the placental barrier, albeit bilayered
in the first trimester, and damage the fetus directly, albeit at low concentration. Here we
examined the responses of human embryonic stem (hES) cells in tissue culture to two metals at low
concentration. We compared direct exposures with indirect exposures across a bi-layered model
of the placenta cell barrier. Direct exposure caused increased DNA damage without apoptosis or
a loss of cell number but with some evidence of altered differentiation. Indirect exposure caused
increased DNA damage and apoptosis but without loss of pluripotency. This was not caused by
metal ions passing through the barrier. Instead the hES cells responded to signalling molecules
(including TNF-α) secreted by the barrier cells. This mechanism was dependent on connexin 43
mediated intercellular âbystander signallingâ both within and between the trophoblast barrier and
the hES colonies. These results highlight key differences between direct and indirect exposure of hES
cells across a trophoblast barrier to metal toxins. It offers a theoretical possibility that an indirectly
mediated toxicity of hES cells might have biological relevance to fetal development
Evaluating the mechanical properties of E-Glass fiber/carbon fiber reinforced interpenetrating polymer networks
Erratum to: Improvement of the surface state of a sandblasted glass by deposing a thin layer of SiO
Theoretical and experimental studies of the magnetocaloric effect on lacunar compounds
International audienc
Interest and durability of multilayers: from model films to complex films
International audienceIn a first part, this paper focuses on the interest of using a multilayer for vacuum insulation panels envelope. It is shown that piling up layers of metallized poly(ethylene terephthalate) does not seem to improve the initial barrier performance. In parallel, a permeation model to predict barrier properties of multilayer films was developed and validated with experimental results. In a second part, durability of a multilayer composite was investigated using accelerated hydrothermal ageing tests. It is shown that physical properties and in particular barrier properties decrease with ageing time. Polyurethane layer used as adhesive system in multilayer films is responsible for complete degradation of aluminum layer after 6 ageing months at 70 degrees C - 90% relative humidity. Copyright (C) 2009 JohnWiley & Sons, Ltd
Assessment of structural, optical, magnetic, magnetocaloric properties and critical phenomena of La0.57Nd0.1Sr0.18Ag0.15MnO3 system at room temperature
International audienc