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1.
Molecules ; 28(4)2023 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-36838957

RESUMEN

The wreck of the Punic ship exhibited at the Archaeological Park of Lilybaeum (Marsala, Italy) is a unique example in the world. In this paper, the investigation of some metal finds (30 nails and 3 fragments of sheathings) belonging to the wreck of the Punic ship is reported. Portable X-ray fluorescence and Raman spectroscopy allowed us to identify the elements and compounds constituting them and make some deductions about their composition. X-ray diffractometry, polarised optical microscopy and scanning electron microscopy of the collected micro-samples allowed us to explain the degradation that occurred in the underwater environment.


Asunto(s)
Uñas , Navíos , Islas , Metales , Espectrometría Raman/métodos
2.
RSC Adv ; 13(7): 4495-4503, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36760299

RESUMEN

The Aeolian cultural heritage preserves hundreds of testimonies of the past that have passed through six millennia of history. Among these, the Archeological Park of the Aeolian Islands with the Museum Luigi Bernabò Brea (Italy) preserves a valuable set of artworks, which are related to a little-known 'popular' figurative heritage. It is an assemblage of small glass foils decorated using the technique of reverse painting, datable to between the end of the 17th century and the end of the 18th century, and actually under investigation by historians. Here, an X-ray fluorescence (XRF) spectroscopy study (performed with portable equipment) is combined with a multivariate approach that allows us to define the best way to process the data to detect compositional differences and similarities among the glass supports. The Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were applied both on normalized spectra and on normalized peak areas in order to establish the chemometric approach with the highest grouping ability. Results showed that the analysis of the normalized area provides the most reliable grouping based on the different elemental compositions, without problems coming from the background or peak-shape distortions. The obtained results can be used by researchers involved in the analysis of XRF data as a guideline to perform chemometrics. Furthermore, regarding the reverse glass, they can be divided into different typologies based on composition differences, providing a further discrimination criterion for historians involved in the study of the collection to determine the provenance and dating of the items.

3.
Langmuir ; 38(38): 11539-11549, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36097705

RESUMEN

A new approach for the synthesis of Y3Al2Ga3O12 (YAGG) nanophosphors allowing the preparation of crystallites with sizes starting from 45 nm is presented. The controllability of the energy and trap density of the resulting material samples by annealing temperature was confirmed by thermoluminescence (TL) measurements. It has been shown that the annealing of samples at temperatures up to 1300 °C does not cause any substantial growth of crystallites, still remaining below 100 nm, but leads to changes in the activation energy of the persistent luminescence (PersL) process. On the other hand, annealing above 1400 °C results in grain growth on the submicron scale, which was confirmed by X-ray powder diffraction (XRPD) and electron transmission microscopy (TEM) measurements. In addition, with an increase in the molar ratio of urea to the total amount of metals used (R), qualitative changes are observed in the PersL process occurring from the excited states of Cr3+ and Pr3+ ions. This proves the influence of the synthesis process, in particular of the metal complexation at its initial stage, on the final structure ordering in the annealed materials. These observations are linked to previously reported defects in the YAGG structure, leading to PersL.

4.
Environ Sci Pollut Res Int ; 29(20): 29510-29523, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34751880

RESUMEN

The conservation of ancient paintings sited in humid environments is an actual challenge for restorers, because it needs the knowledge of the materials the paintings are made up and of their interaction with a peculiar surrounding environment; thus, tailored procedures and strategies aimed at restoring and preserving paintings are necessary. Santa Margherita's cave in Castellammare del Golfo (Trapani, Italy) is a natural cave, containing the remains of paintings, in a poor state of conservation, belonging to an ancient church dated back to the Middle Age. The present manuscript reports the monitoring of environmental conditions (i.e., temperature and humidity) in a full year, as well as a study on the materials constituting the stone support and the paintings together with a survey of the microbial community. The findings allow us to define the causes that mainly involve the degradation of the paintings. In detail, the degradation of the east and the west walls occurred differently because of the exposure to the sea aerosol, which influenced the salt composition, also contributing to diversifying the bacterial community. Some specific actions to plan the conservation and restoration of paintings and to preserve the site are suggested.


Asunto(s)
Microbiota , Pinturas , Bacterias , Humedad , Temperatura
5.
Molecules ; 26(24)2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34946678

RESUMEN

The iconographic heritage is one of the treasures of Byzantine art that have enriched the south of Italy, and Sicily in particular, since the early 16th century. In this work, the investigations of a Sicilian Icon of Greek-Byzantine origin, the Madonna dell'Elemosina, is reported for the first time. The study was carried out using mainly non-invasive imaging techniques (photography in reflectance and grazing visible light, UV fluorescence, infrared reflectography, radiography, and computed tomography) and spectroscopic techniques (X-ray fluorescence and infrared spectroscopy). The identification of the constituent materials provides a decisive contribution to the correct historical and artistic placement of the Icon, a treasure of the Eastern European historical community in Sicily. Some hidden details have also been highlighted. Most importantly, the information obtained enables us to define its conservation state, the presence of foreign materials, and to direct its protection and restoration.

6.
Sci Rep ; 11(1): 23022, 2021 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-34837034

RESUMEN

Two Monterfortino helmets, recovered in the Mediterranean seabed, show unusual features with respect to the more common helmets of the same period and found in underwater environments. Hence, they were investigated by a multi-analytical approach, which allowed us to identify the compounds constituting the helmets and to make some considerations about their metallurgy, although all the metal was converted to degradation products. The helmets, originally made in bronze, have maintained their original shape because of copper sulphides formation. The observed differences in composition between the two helmets were attributed to the position modification, of one of them, into the seabed along centuries. For the first time, a microstructural investigation permits to reconstruct the history of the aging processes involved in the total oxidation of roman bronze helmet metal.

7.
J Prev Med Hyg ; 62(2): E270-E276, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34604565

RESUMEN

INTRODUCTION: The aim of the study was to evaluate the knowledge, attitude and practices towards SARS-CoV-2 among nursing students of University of Palermo during the rapid rise period of the COVID-19 pandemic. MATERIALS AND METHODS: This is cross-sectional study. A survey was provided to all nursing students and consisted of two parts: demographics and Knowledge, Attitude and Practices (KAP) survey. A multivariate linear regression model was used and adjusted Odds Ratios (aOR) are presented. RESULTS: 575 students were interviewed, and their mean age was 22.29 ± 4.2. The overall score indicates good knowledge (p=0.046) and good practices among the four courses of study (p=0.038). Multivariate linear regression showed that Attitude score (b = -0.29; p = 0.024) and Knowledge score (b = 0.10; p = 0.026) adjusted for age, gender, year of study, perceived economic status, perceived health status were significantly associated with Practice score. CONCLUSION: Our results suggest that proper health education is useful for encouraging optimistic attitudes and maintaining safe practices among future category of nurses.


Asunto(s)
COVID-19 , Conocimientos, Actitudes y Práctica en Salud , Estudiantes de Enfermería/psicología , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Pandemias , SARS-CoV-2 , Encuestas y Cuestionarios , Adulto Joven
8.
J Infect Prev ; 22(3): 132-135, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34239611

RESUMEN

The flu vaccination rate is still too low, both among healthcare providers (HCPs) and among health sciences university students. This study aims to assess the reasons of past and future flu vaccination acceptance among health sciences university students, and second, to identify what interventions would be helpful to foster acceptance of the flu vaccination among HCPs. A multicentre cross-sectional study was performed, using a validated questionnaire administered to health sciences students enrolled in 14 Italian universities. A multivariable logistic regression model was used. A total of 3131 questionnaires were collected. The statement that mandatory vaccination is required to increase adhesions to vaccinations (adjusted odds ratio [aOR] = 1.57; 95% confidence interval [CI] = 1.25-1.97), being in favour of this obligation (aOR = 7.91; 95% CI = 2.50-25.02) and considering themselves as people at risk of infection (aOR = 1.96; 95% CI = 1.46-2.64), are associated with having received the vaccination in the past flu season; on the other hand, planning to be vaccinated for the next season to avoid infecting patients is protective (aOR = 0.51; 95% CI = 0.38-0.70). This study shows which beliefs are associated with having joined the previous vaccination campaign in a large sample of HCPs. The acceptance of vaccination is an outcome behaviour resulting from a complex decision-making process. In order to implement coverage of the influenza vaccination in HCPs, it is necessary to implement awareness campaigns and provide specific information for this category of workers.

9.
Nutrients ; 13(4)2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33921674

RESUMEN

BACKGROUND: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people's lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March-May lockdown. METHODS: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. RESULTS: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. CONCLUSIONS: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life.


Asunto(s)
COVID-19/epidemiología , Trastornos Migrañosos/epidemiología , Distanciamiento Físico , Adulto , Control de Enfermedades Transmisibles/métodos , Ejercicio Físico , Conducta Alimentaria , Cefalea/epidemiología , Humanos , Italia/epidemiología , Estilo de Vida , Persona de Mediana Edad , Calidad de Vida , Cuarentena , SARS-CoV-2 , Sueño , Trastornos del Sueño-Vigilia/epidemiología , Encuestas y Cuestionarios
10.
Sci Rep ; 11(1): 141, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-33420267

RESUMEN

Co-doped Ce3+, Cr3+ and Pr3+ yttrium-aluminium-gallium garnet powders of various sizes were obtained by co-precipitation method. The microstructure and morphology were investigated by XRPD, TEM and gas porosimetry. The luminescence properties were studied by excitation and emission spectra, quantum yield and decay times. Thermoluminescence measurements were performed to evaluate the activation energy, traps redistribution and frequency factor. Limitation in the energy transfer between dopant ions in the small particles, traps depth and surface defects were considered and investigated as responsible for the quenching of persistent luminescence. The phosphors annealed at 1100 °C show the optimal persistent luminescence and nano-particle size.

11.
Molecules ; 27(1)2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-35011394

RESUMEN

Spectral preprocessing data and chemometric tools are analytical methods widely applied in several scientific contexts i.e., in archaeometric applications. A systematic classification of natural powdered pigments of organic and inorganic nature through Principal Component Analysis with a multi-instruments spectroscopic study is presented here. The methodology allows the access to elementary and molecular unique benchmarks to guide and speed up the identification of an unknown pigment and its recipe. This study is conducted on a set of 48 powdered pigments and tested on a real-case sample from the wall painting in S. Maria Delle Palate di Tusa (Messina, Italy). Four spectroscopic techniques (X-ray Fluorescence, Raman, Attenuated Total Reflectance and Total Reflectance Infrared Spectroscopies) and six different spectrometers are tested to evaluate the impact of different setups. The novelty of the work is to use a systematic approach on this initial dataset using the entire spectroscopic energy range without any windows selection to solve problems linked with the manipulation of large analytes/materials to find an indistinct property of one or more spectral bands opening new frontiers in the dataset spectroscopic analyses.

12.
Acta Biomed ; 91(12-S): e2020001, 2020 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-33263338

RESUMEN

BACKGROUND: SARS-CoV-2 infection is a global health problem that is primarily detected in Italy with progressive increase in cases and deaths. To facilitate the management of the pandemic in Italy, it is essential to understand the level of attention on COVID-19. The aim of the study was to evaluate the knowledge, attitude and practices towards SARS-CoV-2 among the nursing students of University of Palermo during the rapid rise period of the COVID-19 pandemic. METHODS: The current study was a cross-sectional study. On-line questionnaires were used for the collection of the data by providing a survey in all nursing students. The questionnaire consisted of two parts: demographics and Knowledge, Attitude and Practices (KAP) survey. A multivariate linear regression model was used and adjusted Odds Ratios (aOR) are presented. RESULTS: 525 students were interviewed and their mean age was 21.8. The overall score indicates good practices among the three courses of study (p=0.025). The Multivariable logistic regression showed that the dependent variable "Practice poor score" is statistically significant associated with these independent variables: "Other country of birth" (aOR 17.7, 95% CI 2.31-136.03), "second" (aOR 2.65, 95% CI 1.21-7.80) and "third" (aOR 2.96, 95% CI 1.31-6.72) year of study, "low perceived health status"(aOR 2.35, 95% CI 1.04-5.30) and "Knowledge poor score (aOR 3.05, 95% CI 1.06-8.77). CONCLUSION: Our results suggest that health education programs aimed at improving COVID-19 knowledge are helpful for nursing students to hold optimistic attitudes and maintain appropriate practices.


Asunto(s)
Actitud del Personal de Salud , COVID-19/enfermería , Competencia Clínica , Estudiantes de Enfermería , Estudios Transversales , Femenino , Humanos , Italia/epidemiología , Masculino , Pandemias , Encuestas y Cuestionarios , Adulto Joven
13.
Front Chem ; 8: 699, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32974275

RESUMEN

The biotic deterioration of artifacts of archaeological and artistic interest mostly relies on the action of microorganisms capable of thriving under the most disparate environmental conditions. Thus, to attenuate biodeterioration phenomena, biocides can be used by the restorers to prevent or slow down the microbial growth. However, several factors such as biocide half-life, its wash-out because of environmental conditions, and its limited time of action make necessary its application repeatedly, leading to negative economic implications. Sound and successful treatments are represented by controlled release systems (CRSs) based on porous materials. Here, we report on the design and development of a CRS system based on mesoporous silica nanoparticles (MSNs), as a carrier, and loaded with a biocide. MSNs, with a diameter of 55 nm and cylindrical pores of ca. 3-8 nm arranged as parallel arrays concerning the NP diameter, and with 422 m2/g of specific surface area were synthesized by the sol-gel method assisted by oil in water emulsion. Biocide loading and release were carried out in water and monitored by UV-Vis Spectroscopy; in addition, microbiological assay was performed using as control the MCM-41 mesoporous silica loaded with the same biocide. The role of specific supramolecular interaction in regulating the release is discussed. Further, we demonstrated that this innovative formulation was useful in inhibiting the in vitro growth of Kocuria rhizophila, an environmental Gram-positive bacterial strain. Besides, the CRS here prepared reduced the bacterial biomass contaminating a real case study (i.e., stone derived from the Santa Margherita cave located in Sicily, Italy), after several months of treatment thus opening for innovative treatments of deteriorated stone artifacts.

14.
Acta Biomed ; 91(4): e2020190, 2020 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-33525291

RESUMEN

INTRODUCTION: Cases of measles in some European countries are increasing. The aim of this study is to find the correlation between Google Trends and Wikipedia searches and the real number of cases notified. MATERIALS AND METHODS: The data on Internet searches have been obtained from Google Trends and Wikipedia. The reported cases of measles were selected from January 2013 until December 2018 for Google Trends and July 2015 until December 2018  from for Wikipedia. We have selected data from four European Countries: Italy, France, Germany and Romania. The data extracted from Wikipedia and Google Trends have been moved over time (Lag), one month in the future and one month in the past. Cross-correlation results are obtained as product-moment correlations between the two time series. The statistical analyses have been performed by using the Spearman's rank correlation coefficient or Pearson correlation coefficient. RESULTS: A temporal correlation was observed between the bulletin of ECDC and Wikipedia search trends. For Wikipedia the strongest correlation is at a lag of +1 for rougeole (r=0.9006) and masern (r=0.7023) and at lag 0 for morbillo (r=0.8892) and rujeola (r=0.5462); for Google Trends the strongest correlation at a lag 0 for rougeole (rho=0.7398), symptômes rougeole (rho=0.3399), masern (rho=0.6484), sintomi morbillo (rho=0.6029), rujeola (rho=0.7209), simptome rujeola (rho=0.5297) and at lag -1 for masern symptom (rho=0.4536) and morbillo (rho=0.5804). CONCLUSIONS: Google and Wikipedia could play an important role in surveillance, although these tools need to be combined with traditional surveillance systems.


Asunto(s)
Sarampión , Europa (Continente)/epidemiología , Francia , Alemania , Humanos , Italia , Sarampión/epidemiología , Sarampión/prevención & control , Proyectos Piloto
15.
J Colloid Interface Sci ; 555: 394-402, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31400534

RESUMEN

HYPOTHESIS: Polydopamine (PDA) is widely used as hydrophilic coating for several applications. However, most of the methods studied to improve or manipulate PDA properties are multistep and time-consuming, and there is a need for versatile strategies aimed at controlling and modifying the properties of PDA. EXPERIMENTS: PDA-halloysite nanocomposites were produced under different oxidation conditions in alkaline and acidic media and were characterized by UV-visible and attenuated total refraction- Fourier Transform Infrared spectroscopies, thermogravimetric analysis, porosimetry, scanning electron microscopy, X-ray diffraction and contact angle measurements against the reference PDA polymer. FINDINGS: Inclusion of the inorganic halloysite nanofiller in the PDA component was found to affect the thermal properties of the nanocomposite as well as its structure, depending on the experimental conditions. The ability of the nanocomposites to adsorb organic dyes as possible membrane coatings for environmental remediation was also investigated by different models, suggesting promising applications as adsorbents for the treatment of wastewaters.

16.
Recenti Prog Med ; 110(5): 244-250, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31140457

RESUMEN

Introduction: We aimed at carrying out a quantitative and qualitative analysis of claims for adverse events addressed to Palermo University Hospital Policlinico "Paolo Giaccone" in order to promote evidence-based interventions and increase patient safety. Methods: A retrospective study of 296 claims collected between 1st of January, 2014 and 31st of December, 2017 by Quality and Clinical Risk Management staff unit was performed along with descriptive analysis of any associated determinant factors. Results: The most frequent causes of claims consisted of wrong surgical procedures (33.8%), mistaken diagnoses (18.6%), falls (17.6%), infections (6.4%), postoperative complications (5.4%) and wrong therapies (3.1%). At the end of the survey, the judicial process was not concluded in the majority of cases (82.8%). Claims were closed by receipt payment in 12.2% of cases, without any payment in 5.1%. Conclusions: Clinical risk management plays a pivotal role in providing information and tools to prevent medical adverse events, avoid claims addressed to hospitals and improve the quality of health care.


Asunto(s)
Atención a la Salud/normas , Errores Médicos/estadística & datos numéricos , Calidad de la Atención de Salud/normas , Gestión de Riesgos/métodos , Atención a la Salud/estadística & datos numéricos , Medicina Basada en la Evidencia , Hospitales Universitarios , Humanos , Italia , Seguridad del Paciente , Estudios Retrospectivos , Encuestas y Cuestionarios
18.
Sci Rep ; 9(1): 3368, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30833596

RESUMEN

Ce:YAG nanostructures (Ce:YAG = Cerium in Yttrium Aluminium Garnet), easy to control and shape, have been prepared via templating approach using natural and synthetic materials (i.e. paper, cotton wool and glass wool) previously soaked with a gel-like metals precursor and then thermally treated to achieve the wished morphology. The final material, otherwise difficult to process, can be easily moulded, it is lightweight, portable and forms, at the nanoscale, homogeneous layers of interconnected but not agglomerated nanoparticles (15 ± 5 nm). Using the same synthetic route, called Urea-Glass-Route, but in absence of a template, extremely pure Ce:YAG nanoparticle (45 ± 5 nm) can be also prepared, highly crystalline and well-defined in size and shape. Both structural and optical properties of the final materials were investigated, showing high optical quality. The support allows the production of a multifunctional material with mouldable shape and potential lighting application for large structures combining the strength, chemical durability, fire resistance, and translucency of glass fibres. Last, but not least, the synthetic path also allows an easy scaling up of the process: the first, key step for practical application of nanosized rare-earth doped YAG on large scale.

19.
Ment Illn ; 11(2): 25-31, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32742623

RESUMEN

PURPOSE: Depression is a common and serious medical illness, considered as a public health issue because it interferes with the interpersonal, social and professional functioning of the individual, and its frequency is constantly increasing. According to a recent review, approximately 34 per cent of nursing students had experienced depression worldwide. The university period may represent a moment in which the mental well-being of students is subjected to stress with a relative predisposition to the development of diseases related to mood disorders. The purpose of this study is to estimate the prevalence and examine the socio-demographic correlates of depressive symptomatology. DESIGN/METHODOLOGY/APPROACH: In April 2019, a questionnaire was administered to all the nursing students of University of Palermo of the three years of course, accompanied by informed consent. Multivariable logistic regression was performed. The statistical significance level chosen for all analyses was 0.05. The results were analyzed using the STATA statistical software version 14. Results are expressed as adjusted odds ratio (aOR) with 95 per cent confidence intervals. FINDINGS: The sample consists of 493 students who completed the questionnaire, and the average age of the sample participants is 21.88 years. The multivariable logistic regression model shows that the risk to have depressive symptomatology is significantly associated with the following independent variables: female gender (aOR 1.91), being single (aOR 1.87), second year of study (aOR 1.94), third year of study (aOR 1.92), not performing regular physical activity (aOR 1.78) and perceived low health status (aOR 3.08). ORIGINALITY/VALUE: This study shows that belonging to the female gender, being further along in the years of study, having a chronic illness and perceiving a low state of health are all factors that can increase the risk of developing the symptoms of depression; rather, regular physical activity, friendship and romantic relationships can be considered factors protecting them from the risk of falling into depression that can undermine both the study and work performance. Certainly, it is important to analyze all the involved variables to improve the global health not only of the nursing students but of all the students.

20.
J Hazard Mater ; 286: 474-83, 2015 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-25615695

RESUMEN

A class of inorganic binders, also known as geopolymers, can be obtained by alkali activation of aluminosilicate powders at room temperature. The process is affected by many parameters (curing time, curing temperature, relative humidity etc.) and leads to a resistant matrix usable for inertization of hazardous waste. In this study an industrial liquid waste containing a high amount of chromium (≈ 2.3 wt%) in the form of metalorganic salts is inertized into a metakaolin based geopolymer matrix. One of the innovative aspects is the exploitation of the water contained in the waste for the geopolymerization process. This avoided any drying treatment, a common step in the management of liquid hazardous waste. The evolution of the process--from the precursor dissolution to the final geopolymer matrix hardening--of different geopolymers containing a waste amount ranging from 3 to 20%wt and their capability to inertize chromium cations were studied by: i) the leaching tests, according to the EN 12,457 regulation, at different curing times (15, 28, 90 and 540 days) monitoring releases of chromium ions (Cr(III) and Cr(VI)) and the cations constituting the aluminosilicate matrix (Na, Si, Al); ii) the humidity variation for different curing times (15 and 540 days); iii) SEM characterization at different curing times (28 and 540 days); iv) the trend of the solution conductivity and pH during the leaching test; v) the characterization of the short-range ordering in terms of TOT bonds (where T is Al or Si) by (29)Si and (27)Al solid state magic-angle spinning nuclear magnetic resonance (ss MAS NMR) for geopolymers containing high amounts of waste (10-20%wt). The results show the formation of a stable matrix after only 15 days independently on the waste amount introduced; the longer curing times increase the matrices stabilities and their ability to immobilize chromium cations. The maximum amount of waste that can be inertized is around 10 wt% after a curing time of 28 days.


Asunto(s)
Silicatos de Aluminio/química , Cromo/química , Eliminación de Residuos Líquidos/métodos , Residuos Industriales , Espectroscopía de Resonancia Magnética
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