Transparent conducting electrodes (TCE) are extensively applied in a great range of optoelectronic and photovoltaic equipment (e.g., solar cells, touch panels, and flexible devices). Carbon-based ...nanomaterials are considered as suitable replacements to substitute traditional materials to manufacture TCE due to their remarkable characteristics, for example, high optical transmittance and outstanding electrical properties. In comparison with traditional indium tin oxide electrodes, carbon-based electrodes show good mechanical properties, chemical stability, and low cost. Nevertheless, major issues related to the development of good quality manufacture methods to produce carbon-based nanomaterials have to be overcome to meet massive market requirements. Hence, the development of alternative TCE materials as well as appropriate large production techniques that meet the requirements of a proper sheet resistance along with a high optical transparency is a priority. Therefore, in this work, we summarize and discuss novel production and synthesis methods, chemical treatments, and hybrid materials developed to satisfy the worldwide request for carbon-based nanomaterials.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Hazardous materials like barium and lead present in discarded Cathode Ray Tubes, CRT's, may represent a big problem to the environment if they are not properly disposed. In the present study, ...solidification/stabilization of crushed waste CRT (CRT glass particles), through a calcined kaolin base-geopolymer as metal-immobilizer is presented. Two different compositions of raw materials using 5, 10, and 20% wt of CRT glass particles were studied. The geopolymers were analyzed by XRD, SEM, TG-DTA/DSC, FTIR, leaching tests. The microhardness of coatings on mild steel was tested. The results and the differences in properties are explained based on the microstructure evolution of the geopolymer with CRT glass particles. The results showed that low alkaline medium was effective in the encapsulation of toxic heavy metals from the CRT glass even though they were used as coatings on mild steel samples.
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•Geopolymers encapsulate CRT glass particles efficiently.•Toxic heavy metals are successfully immobilized in calcined kaolin based geopolymer.•The CRT glass particles are well anchored in a dense matrix.•Leaching testing showed values of heavy metals within the range of Standards.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Nowadays, the increase in energy demand has resulted in exhaustion of energy resources, climate change, and environmental pollution. A way to approach this issue and improve the environment is by ...reducing the consumption of energy in buildings, either by the employment of new materials or by using unified energy storage systems. Phase Change Materials (PCM's) which can be used to store thermal energy as latent heat, can be an alternative to reduce the consumption of energy in either houses or buildings. The key use in this alternative is the segregation of the PCM from the supporting material that may result in a damage to the human health of inhabitants. In the present paper, a non-toxic metakaolinite-based geopolymer was studied as an alternative to imbed dodecanol by using Hexadecyltrimethyl ammonium bromide (CTAB) as a coupling agent and a surface treatment with Tetraethyl orthosilicate (TEOS) to prevent segregation was assessed. Dodecanol-geopolymer samples were characterized by FT-IR, XRD and SEM; and energy storage and phase change temperature were measured by DSC.
Finally, dodecanol load capacity was calculated. The effectiveness of CTAB as a coupling agent between the dodecanol and the geopolymer was showed while the surface treatment increases the load capacity of the dodecanol-geopolymer system studied.
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•A non-toxic metakaolinite-based geopolymer is an alternative to confine dodecanol.•Hexadecyltrimethyl ammonium bromide was effective as coupling agent.•The load capacity of the dodecanol-geopolymer system is adequate to store energy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Alzheimer's disease (AD) is the most common neurodegenerative disease worldwide. Histopathologically, AD presents with two hallmarks: neurofibrillary tangles (NFTs), and aggregates of amyloid β ...peptide (Aβ) both in the brain parenchyma as neuritic plaques, and around blood vessels as cerebral amyloid angiopathy (CAA). According to the vascular hypothesis of AD, vascular risk factors can result in dysregulation of the neurovascular unit (NVU) and hypoxia. Hypoxia may reduce Aβ clearance from the brain and increase its production, leading to both parenchymal and vascular accumulation of Aβ. An increase in Aβ amplifies neuronal dysfunction, NFT formation, and accelerates neurodegeneration, resulting in dementia. In recent decades, therapeutic approaches have attempted to decrease the levels of abnormal Aβ or tau levels in the AD brain. However, several of these approaches have either been associated with an inappropriate immune response triggering inflammation, or have failed to improve cognition. Here, we review the pathogenesis and potential therapeutic targets associated with dysfunction of the NVU in AD.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
C-sp
2
(graphite) impurities are undesirable in synthetic diamond electrodes (C-sp
3
), because they can affect the electrochemical response. In this work, we demonstrate that C-sp
3
surfaces can be ...activated successfully by applying an anodic current density corresponding to sufficiently high potential where the hydroxyl radicals (
●
OH) are generated. The effectiveness of this activation process was verified by Raman spectroscopy, X-ray diffraction, scanning electron microscopy, and cyclic voltammetry.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The energy sector is one of the fields of interest for different nations around the world. Due to the current fossil fuel crisis, the scientific community develops new energy-saving experiences to ...address this concern. Buildings are one of the elements of higher energy consumption, so the generation of knowledge and technological development may offer solutions to this energy demand, which are more than welcome. Phase change materials (PCMs) included in building elements such as wall panels, blocks, panels or coatings, for heating and cooling applications have been shown, when heating, to increase the heat storage capacity by absorbing heat as latent heat. Therefore, the use of latent heat storage systems using phase change materials (PCMs) has been investigated within the last two decades. In the present review, the macro and micro encapsulation methods for construction materials are reviewed, the former being the most viable method of inclusion of PCMs in construction elements. In addition, based on the analysis of the existing papers on the encapsulation process of PCMs, the importance to pay more attention to the bio-based PCMs is shown, since more research is needed to process such PCMs. To determine its thermophysical and mechanical behavior at the micro and macro levels, in order to see the feasibility of substituting petroleum-based PCMs with a more environmentally friendly bio-based one, a section devoted to the excellent PCM with lightweight aggregate (PCM-LWA concrete) is presented due to the lack of description given in other reviews.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The current pandemic caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a public health emergency. To date, March 1, 2021, coronavirus disease 2019 (COVID-19) ...has caused about 114 million accumulated cases and 2.53 million deaths worldwide. Previous pieces of evidence suggest that SARS-CoV-2 may affect the central nervous system (CNS) and cause neurological symptoms in COVID-19 patients. It is also known that angiotensin-converting enzyme-2 (ACE2), the primary receptor for SARS-CoV-2 infection, is expressed in different brain areas and cell types. Thus, it is hypothesized that infection by this virus could generate or exacerbate neuropathological alterations. However, the molecular mechanisms that link COVID-19 disease and nerve damage are unclear. In this review, we describe the routes of SARS-CoV-2 invasion into the central nervous system. We also analyze the neuropathologic mechanisms underlying this viral infection, and their potential relationship with the neurological manifestations described in patients with COVID-19, and the appearance or exacerbation of some neurodegenerative diseases.
The construction industry is one of the largest and most active growth sectors worldwide. It presents an important environmental impact, and one way to reduce the impact of the construction activity ...is to substitute pozzolanic materials for ordinary Portland cement. In this work, barley straw, barley straw ash, and other natural and artificial pozzolans from Mexico were characterized and compared. Also, the pozzolanic activity of barley straw ash was compared with the pozzolanic properties of some natural and artificial pozzolans from Mexico. Materials considered included recycled dust of fired clay brick, fly ash, volcanic ash, and wheat straw ash.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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