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1.
Public Health ; 225: 127-132, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37924636

ABSTRACT

OBJECTIVES: To evaluate gender differences in workplace violence (WPV) against physicians and nurses in Latin America. STUDY DESIGN: Cross-sectional study. METHODS: A cross-sectional electronic survey was conducted between January 11 and February 28, 2022. A prespecified gender analysis was performed. RESULTS: Among the 3056 responses to the electronic survey, 57% were women, 81.6% were physicians, and 18.4% were nurses. At least one act of violence was experienced by 59.2% of respondents, with verbal violence being the most common (97.5%). Women experienced more WPV than men (65.8% vs 50.4%; P < 0.001; odds ratio [OR]: 1.89; 95% confidence interval [CI]: 1.63-2.19). Women were more likely to report at least one episode of WPV per week (19.2% vs 11.9%, P < 0.001), to request for psychological help (14.5% vs 9%, P = 0.001) and to experience more psychosomatic symptoms. In addition, women were more likely to report having considered changing their job after an aggression (57.6% vs 51.3%, P = 0.011) and even leaving their job (33% vs 25.7%, P = 0.001). In a multivariate analysis, being a woman (OR: 1.76), working in emergency departments (OR: 1.99), and with COVID-19 patients (OR: 3.3) were independently associated with more aggressive interactions, while older age (OR: 0.95) and working in a private setting (OR: 0.62) implied lower risk. CONCLUSIONS: Women are more likely to experience WPV and to report more psychosomatic symptoms after the event. Preventive measures are urgently needed, with a special focus on high-risk groups such as women.


Subject(s)
Cardiology , Physicians , Workplace Violence , Male , Humans , Female , Workplace Violence/psychology , Cross-Sectional Studies , Sex Factors , Latin America/epidemiology , Surveys and Questionnaires , Physicians/psychology
2.
Polymers (Basel) ; 15(18)2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37765626

ABSTRACT

Strawberries are highly consumed around the world; however, the post-harvest shelf life is a market challenge to mitigate. It is necessary to guarantee the taste, color, and nutritional value of the fruit for a prolonged period of time. In this work, a nanocoating based on chitosan and ZnO nanoparticles for the preservation of strawberries was developed and examined. The chitosan was obtained from residual shrimp skeletons using the chemical method, and the ZnO nanoparticles were synthesized by the close-spaced sublimation method. X-ray diffraction, scanning electron microscopy, electron dispersion analysis, transmission electron microscopy, and infrared spectroscopy were used to characterize the hybrid coating. The spaghetti-like ZnO nanoparticles presented the typical wurtzite structure, which was uniformly distributed into the chitosan matrix, as observed by the elemental mapping. Measurements of color, texture, pH, titratable acidity, humidity content, and microbiological tests were performed for the strawberries coated with the Chitosan/ZnO hybrid coating, which was uniformly impregnated on the strawberries' surface. After eight days of storage, the fruit maintained a fresh appearance. The microbial load was reduced because of the synergistic effect between chitosan and ZnO nanoparticles. Global results confirm that coated strawberries are suitable for human consumption.

3.
Eur Arch Paediatr Dent ; 23(2): 233-241, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34365570

ABSTRACT

PURPOSE: The aim of this study was to evaluate in vitro, the shear bond strength (SBS) and adhesive remnant index (ARI) of pit and fissure sealants (PFS) after enamel conditioning with different new-generation self-etching (SE) agents; additionally, enamel etching patterns were assessed. METHODS: Healthy unerupted third molars surgically removed for therapeutic reasons (n = 25p/g), were randomly assigned to six groups. Conventional etching (CE) or SE was applied prior to pit and fissure sealants bonding. Enamel conditioned surfaces were evaluated by SEM at × 500, × 1000, and × 2000 magnification to determine etching patterns. Subsequently, 25 PFS blocks (3 × 2 × 1.5 mm) p/g were bonded to enamel surface. Samples were stored in water at 37 °C for 24 h, previous to SBS and ARI test. One-way ANOVA and Tamhane statistic tests were used for SBS; while Mann-Whitney U and Kruskal-Wallis were employed for ARI (p ≤ 0.05). RESULTS: For SBS test, CE_PFS_3M and SE1_PFS_Shofu groups showed the lowest values (8.74 ± 4.02 and 8.75 ± 3.90, respectively). The highest scores were observed in SE_PFS_Kuraray group (13.46 ± 5.83). Significant differences in SBS and ARI assessments were found. All experimental groups showed type 1 etching pattern. CONCLUSION: The etching pattern was less pronounced in self-etching groups, which showed an equal or superior in vitro performance compared to conventional etching agents. The clinical use of self-etching agents could be recommended before pit and fissure sealants application in new dental protocols. The best in vitro performance was observed when both applied materials, self-etching agent and pit and fissure sealant have 10-methacryloyloxydecyl dihydrogen phosphate in their chemical composition.


Subject(s)
Dental Bonding , Pit and Fissure Sealants , Acid Etching, Dental/methods , Dental Cements , Dental Enamel , Dental Stress Analysis , Humans , Materials Testing , Resin Cements/chemistry , Shear Strength , Surface Properties
4.
Chemosphere ; 288(Pt 2): 132550, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34656622

ABSTRACT

The final disposal of waste generated by human activities has been turned into a great challenge; until now, little attention has been paid to organic waste, particularly from the restaurant sector. This work describes the process of obtaining calcium carbonate contained in oyster and clam shells re-collected in seafood restaurants. The IR absorption spectra of all the samples revealed the presence of characteristic bands of the carbonate group located at 872, 712 and 1414 cm-1; the peak at 1081 cm-1 of the clamshells confirms the presence of the aragonite phase. The SEM images allow observing a granular morphology whose agglomerates having a size within the range of 0.5-15 µm in brown shells, and a lower dispersion prevails in the grey species and oyster shells that go from 0.3 to 5.9 µm. All of the shells were found to be composed of carbon (C), oxygen (O2) and calcium (Ca) in different concentrations. The calcium carbonate obtained from clamshells has an orthorhombic crystalline structure, while the oyster carbonate has a rhombohedral structure as the calcium carbonate used in the construction industry; the morphology particles also coincide with each other. The material obtained combined with a mixture composed of resin, cellulose, and granules were used to prepare a paste, which was used as a residential finish.


Subject(s)
Calcium Carbonate , Ostreidae , Animals , Calcium, Dietary , Humans , Oxygen , Seafood
8.
Ultrason Sonochem ; 72: 105417, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33352467

ABSTRACT

Recently, chitin and chitosan are widely investigated for food preservation and active packaging applications. Chemical, as well as biological methods, are usually adopted for the production of these biopolymers. In this study, modification to a chemical method of chitin synthesis from shrimp shells has been proposed through the application of high-frequency ultrasound. The impact of sonication time on the deproteinization step of chitin and chitosan preparation was examined. The chemical identities of chitin and chitosan were verified using infrared spectroscopy. The influence of ultrasound on the deacetylation degree, molecular weight and particle size of the biopolymer products was analysed. The microscopic characteristics, crystallinity and the colour characteristics of the as-obtained biopolymers were investigated. Application of ultrasound for the production of biopolymers reduced the protein content as well as the particle size of chitin. Chitosan of high deacetylation degree and medium molecular weight was produced through ultrasound assistance. Finally, the as-derived chitosan was applied for beef preservation. High values of luminosity, chromatid and chrome were noted for the beef samples preserved using chitosan films, which were obtained by employing biopolymer subjected to sonication for 15, 25 and 40 min. Notably; these characteristics were maintained even after ten days of packaging. The molecular weight of these samples are 73.61 KDa, 86.82 KDa and 55.66 KDa, while the deacetylation degree are 80.60%, 92.86% and 94.03%, respectively; in the same order, the particle size of chitosan are 35.70 µm, 25.51 µm and 20.10 µm.


Subject(s)
Chitin/chemistry , Chitosan/chemistry , Proteins/isolation & purification , Sonication , Acetylation , Animals , Molecular Weight , Proteins/analysis , Proteins/chemistry
9.
BJOG ; 128(5): 908-915, 2021 04.
Article in English | MEDLINE | ID: mdl-33187026

ABSTRACT

OBJECTIVE: To demonstrate that delayed cord clamping (DCC) is safe in mothers with confirmed SARS-CoV-2 infection. DESIGN, SETTING AND PARTICIPANTS: Prospective observational study involving epidemiological information from 403 pregnant women with SARS-CoV-2 between 1 March and 31 May 2020. Data were collected from 70 centres that participate in the Spanish Registry of COVID-19. METHODS: Patients' information was collected from their medical chart. MAIN OUTCOMES AND MEASURES: The rate of perinatal transmission of SARS-CoV-2 and development of the infection in neonates within 14 days postpartum. RESULTS: The early cord clamping (ECC) group consisted of 231 infants (57.3%) and the DCC group consisted of 172 infants (42.7%). Five positive newborns (1.7% of total tests performed) were identified with the nasopharyngeal PCR tests performed in the first 12 hours postpartum, two from the ECC group (1.7%) and three from the DCC group (3.6%). No significant differences between groups were found regarding neonatal tests for SARS-CoV-2. No confirmed cases of vertical transmission were detected. The percentage of mothers who made skin-to-skin contact within the first 24 hours after delivery was significantly higher in the DCC group (84.3% versus 45.9%). Breastfeeding in the immediate postpartum period was also significantly higher in the DCC group (77.3% versus 50.2%). CONCLUSIONS: The results of our study show no differences in perinatal outcomes when performing ECC or DCC, and skin-to-skin contact, or breastfeeding. TWEETABLE ABSTRACT: This study demonstrates that delayed cord clamping is safe in mothers with confirmed SARS-CoV-2 infection.


Subject(s)
COVID-19 , Constriction , Delivery, Obstetric , Infectious Disease Transmission, Vertical , Pregnancy Complications, Infectious , SARS-CoV-2/isolation & purification , Umbilical Cord/surgery , Adult , Breast Feeding/methods , Breast Feeding/statistics & numerical data , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19/transmission , Delivery, Obstetric/methods , Delivery, Obstetric/statistics & numerical data , Female , Humans , Infant, Newborn , Infectious Disease Transmission, Vertical/prevention & control , Infectious Disease Transmission, Vertical/statistics & numerical data , Kangaroo-Mother Care Method/methods , Kangaroo-Mother Care Method/statistics & numerical data , Pregnancy , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/prevention & control , Pregnancy Outcome/epidemiology , Spain/epidemiology , Time-to-Treatment
11.
Sci Rep ; 10(1): 19017, 2020 11 04.
Article in English | MEDLINE | ID: mdl-33149151

ABSTRACT

The variability in the host immune response directed against dengue virus (DENV) has demonstrated the need to understand the immune response associated with protection in incident infection. The objective was to estimate the association between serostatus and the risk of incident DENV infection. We used a prospective study from 2014 to 2016 in the localities of Axochiapan and Tepalcingo, Morelos, Mexico. We recruited 966 participants, of which, according to their infection history registered were categorized in four groups. To accomplish the objectives of this study, we selected to 400 participants older than 5 years of age were followed for 2.5 years. Blood samples were taken every 6 months to measure serological status and infection by ELISA. In individuals with at least two previous infections the risk of new infection was lower compared to a seronegative group (hazard ratio adjusted 0.49, 95% CI 0.24-0.98), adjusted for age and locality. Therefore, individuals who have been exposed two times or more to a DENV infection have a lower risk of re-infection, thus showing the role of cross-immunity and its association with protection.


Subject(s)
Dengue/epidemiology , Endemic Diseases , Adolescent , Adult , Aged , Aged, 80 and over , Child , Dengue/blood , Female , Humans , Incidence , Male , Mexico/epidemiology , Middle Aged , Prospective Studies , Risk Factors , Seroepidemiologic Studies , Young Adult
12.
Enferm. univ ; 16(1): 105-116, ene.-mar. 2019. tab
Article in Spanish | LILACS-Express | LILACS, BDENF - Nursing | ID: biblio-1001928

ABSTRACT

Introducción Es reconocido que el personal de enfermería es quien tiene mayor interacción con el paciente, por lo que se ve obligado a contar con conocimientos y experiencia suficiente que permita identificar y atender las necesidades de individuos que sufren de enfermedad cerebrovascular. Esta condición de salud puede ser secundaria a la ruptura de un aneurisma, lo que conduce al paciente a un estado crítico; además, puede traducirse en riesgo para el equilibrio financiero de la familia y el Sistema Sanitario. Métodos: Se desarrollaron las etapas del proceso de cuidado de enfermería centradas en una situación real de la práctica clínica durante el periodo postoperatorio de una paciente sometida a clipaje de aneurisma. Se utilizó el modelo de patrones funcionales de Marjory Gordon para la recolección de los datos; además de la taxonomía NANDA-NIC-NOC. Resultados: Se presentan los planes de cuidado en los que se centró la intervención de enfermería en la paciente valorada. Así como la evaluación del proceso en las dimensiones de estructura, proceso y resultado. Discusión/conclusiones: El EVC secundario a ruptura de aneurisma cerebral es una situación grave y devastadora para la familia y el sistema sanitario. Por tanto, una adecuada atención de enfermería a este problema es de la mayor importancia.


Introduction: It is well acknowledged that nursing staff have the greatest interaction with patients and thus, nurses need to have sufficient knowledge and experience to identify the diverse needs, for example of those patients suffering from cerebrovascular disease. This condition can be a consequence of a ruptured aneurysm, which can in turn lead the patient to a critical status jeopardizing the financial equilibrium of his/her family and the health system. Methods: The nursing process stages were developed during the postsurgical period of a patient who underwent an aneurysm clipping. The Gordon's functional health patterns model was used to collect data, in addition to the NANDA/NIC/NOC taxonomy. Results: Care plans derived from the nursing intervention were presented, as well as the related assessment in terms of the structure, process, and results dimensions. Discussion/Conclusion: The CVE secondary to the rupture of an aneurysm is a serious and devastating situation for the patient, his/her family, and the health system, therefore, an adequate related nursing attention becomes of the most importance.


Introdução: Reconhece-se que os enfermeiros têm maior interação com o paciente, sendo obrigados a ter conhecimento e experiência suficientes para identificar e atender às necessidades dos indivíduos portadores de doença cerebrovascular. Essa condição de saúde pode ser secundária à ruptura de um aneurisma, que leva o paciente a um estado crítico; além disso, pode ser traduzido em risco para o equilíbrio financeiro da família e do Sistema de Saúde. Métodos: Desenvolveram-se as etapas do processo de cuidar em enfermagem, enfocando uma situação real da prática clínica no pós-operatório de um paciente submetido a clipagem de aneurisma. O modelo de padrões funcionais de Marjory Gordon foi utilizado para coleta de dados; além da taxonomia NANDA-NIC-NOC. Resultados: São apresentados planos de cuidados em que a intervenção de enfermagem foi focada no paciente valorizado. Assim como a avaliação do processo nas dimensões de estrutura, processo e resultado. Discussão / conclusões: A EVC secundária a um aneurisma cerebral roto é uma situação grave e devastadora para a família e o sistema de saúde. Portanto, cuidados de enfermagem adequados para este problema são de extrema importância.


Subject(s)
Humans , Male , Female , Patients , Postoperative Period , Nursing
13.
J Nucl Cardiol ; 26(6): 1844-1852, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30288680

ABSTRACT

BACKGROUND: Patients with chest pain and no obstructive coronary artery disease have shown a high incidence of major adverse cardiovascular events (MACE). We evaluated the role of absolute myocardial perfusion quantification in predicting all-cause mortality and MACE during long-term follow-up in this group of patients. METHODS: We studied 79 patients who underwent Nitrogen-13 ammonia PET for quantification of global myocardial blood flow (MBF) and myocardial flow reserve (MFR) due to suspected impaired myocardial perfusion. Patients with coronary artery disease (i.e., > 30% stenosis in one or more coronary arteries) were excluded. We assessed all-cause mortality and MACE. MACE was defined as the composite incidence of death, myocardial infarction (MI), or hospitalization due to heart failure. RESULTS: Median follow-up was 8 (IQR: 3-14) years. Univariate Cox regression showed that only MFR (P = 0.01) was a predictor of all-cause mortality. Univariate Cox regression analysis showed that both MFR and Stress MBF were predictors of the composite endpoint of MACE (P < 0.001 and P = 0.01, respectively). CONCLUSION: Quantitative assessment of myocardial perfusion may predict all-cause mortality and MACE in patients with chest pain and normal coronary arteries in the long-term follow-up.


Subject(s)
Chest Pain/diagnostic imaging , Coronary Vessels/diagnostic imaging , Heart/diagnostic imaging , Myocardium/pathology , Adult , Ammonia , Chest Pain/therapy , Female , Follow-Up Studies , Heart Failure/diagnostic imaging , Heart Failure/mortality , Heart Failure/therapy , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Myocardial Perfusion Imaging , Nitrogen Radioisotopes , Positron-Emission Tomography , Prognosis , Proportional Hazards Models , Retrospective Studies
14.
R Soc Open Sci ; 5(8): 180962, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30225084

ABSTRACT

Wet chemical synthesis of hydroxyapatite (HAp) nanostructures was carried out with different solution pH values (9, 10 and 11) and sintering temperatures (300°C, 500°C, 700°C and 900°C). The effects of pH and sintering temperature on the structural and morphological properties of nanocrystalline HAp powders were presented. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were performed to obtain the crystalline structure, chemical composition, morphology and particle size of the HAp powders. The TEM analysis is used in order to observe the rod- and flake-like HAp structures. XRD confirms the presence of both HAp hexagonal and monetite phases, although the monetite phase was less abundant in the resultant powders. Increase in pH reduced the monetite phase and enhanced Ca/P ratio from 1.7 to 1.83. Additionally, an increment in sintering temperature increased the crystallite size from 20 to 56 nm. The SEM analysis revealed the formation of semi-spherical and flake-like HAp structures with preferential flake morphology. An increase in pH and sintering temperature resulted in the growth and coalescence of crystals resulting in a porous capsular morphology. The FTIR analysis confirmed the reduction of carbonate stretching modes with an increase in pH and H-O-H antisymmetric stretching mode is eliminated for powders sintered at 900°C confirming the formation of stable and porous HAp powders.

15.
J Mater Sci Mater Med ; 29(5): 52, 2018 May 02.
Article in English | MEDLINE | ID: mdl-29721617

ABSTRACT

This paper focus on physicochemical changes in bio-hydroxyapatite (BIO-HAp) from bovine femur obtained by calcination at high temperatures: 520-620 (each 20 °C) at 7.4 °C/min and from 700 to 1100 °C (each 100 °C) at three heating rates: 7.4, 9.9, and 11.1 °C/min. BIO-HAp samples were obtained using a multi-step process: cleaning, milling, hydrothermal process, calcination in an air atmosphere, and cooling in furnace air. Inductively Couple Plasma (ICP) showed that the presence of Mg, K, S, Ba, Zn, and Na, is not affected by the annealing temperature and heating rate. While Scanning Electron Microscopy (SEM) images showed the continuous growth of the HAp crystals during the calcination process due to the coalescence phenomenon, and the Full Width at the Half Maximum for the X-ray patterns for temperatures up to 700 is affected by the annealing temperature and the heating rate. Through X-ray diffraction, thermal, and calorimetric analysis (TGA-DSC), a partial dehydroxylation of hydroxyapatite was found in samples calcined up to 900 °C for the three heating rates. Also, Ca/P molar ratio decreased for samples calcined up to 900 °C as a result of the dehydroxylation process. NaCaPO4, CaCO3, Ca3(PO4)2, MgO, and Ca(H2PO4)2 are some phases identified by X-ray diffraction; some of them are part of the bone and others were formed during the calcination process as a function of annealing temperature and heating rate, as it is the case for MgO.


Subject(s)
Bone and Bones/chemistry , Chemical Phenomena , Cold Temperature , Durapatite/chemistry , Durapatite/isolation & purification , Hot Temperature , Animals , Biological Products/chemistry , Cattle , Materials Testing , Microscopy, Electron, Scanning , Minerals/chemistry , Phase Transition , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
17.
J Nucl Cardiol ; 24(5): 1674-1679, 2017 10.
Article in English | MEDLINE | ID: mdl-27506703

ABSTRACT

BACKGROUND: While 18F-fluorodeoxyglucose and 18F-sodium fluoride with positron emission tomography relate with inflammation and calcification, their role in the assessment of patients with Takayasu arteritis has not yet been studied. METHODS: We present 5 patients with suspected active metabolic disease who underwent PET with 18F-fluorodeoxyglucose and 18F-sodium fluoride in order to explore the locations and correlations of 18F-fluorodeoxyglucose and 18F-sodium fluoride uptakes. Diagnosis of metabolic active disease was based on 18F-fluorodeoxyglucose uptake. RESULTS: We studied 3 female patients and 2 male patients. Median age was 29 years (min: 19 max: 63). In areas with atherosclerotic plaques, we found a negative correlation between 18F-sodium fluoride and 18F-fluorodeoxyglucose uptakes (r = -0.78) (P = .001). Meanwhile, in areas with only metabolic active disease, we found a positive correlation between 18F-sodium fluoride and 18F-fluorodeoxyglucose uptakes (r = 0.94) (P = .019). CONCLUSIONS: In Takayasu arteritis, 18F-sodium fluoride uptake can document different stages of metabolic disease, even in the absence of active metabolic disease or symptoms.


Subject(s)
Fluorine Radioisotopes/pharmacokinetics , Positron-Emission Tomography , Sodium Fluoride/pharmacokinetics , Takayasu Arteritis/diagnostic imaging , Adult , Aorta/diagnostic imaging , Calcinosis/diagnostic imaging , Female , Fluorodeoxyglucose F18/pharmacokinetics , Humans , Inflammation , Male , Middle Aged , Young Adult
18.
Appl Opt ; 55(19): 5267-72, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-27409220

ABSTRACT

Light-emitting-diode (LED)-based solid-state lighting has become a real option for private and public lighting after achieving high total luminous flux (TLF) and luminous efficacy levels, thus promoting the development of energy efficient use regulation to be fulfilled by LED lamps and LED luminaires. Here, we propose a photometer-quality-based fast-checking criterion. This allows photometric technicians to perform a quick evaluation of the photometric head spectral response quality effect on the LED source spectral mismatch correction factor-when determining the TLF and luminous efficacy minimum approved levels-performance parameters subject to mandatory verification by the conformity assessment procedures technically supporting the corresponding regulation. The proposed criterion applies for a wide range of photometric detector heads' qualities (2.6%≤f1'≤36.4%).

19.
Toxicol Lett ; 228(2): 103-10, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-24793716

ABSTRACT

Large efforts are invested on the development of in vitro tests to evaluate nanomaterial (NM) toxicity. In order to assess the relevance of the adverse effects identified in in vitro toxicity tests a thorough understanding of the biokinetics of NMs is critical. We used different in vitro and in vivo test methods to evaluate cell uptake and oral absorption of titanium dioxide nanoparticles (TiO2 NPs). These NPs were readily uptaken by A549 cells (carcinomic human alveolar basal epithelial cells) in vitro. Such rapid uptake contrasted with a very low oral absorption in a differentiated Caco-2 monolayer system (human epithelial colorectal adenocarcinoma cells) and after oral gavage administration to rats. In this oral study, no significant increase in the levels of titanium was recorded by ICP-MS in any of the tissues evaluated (including among other: small intestine, Peyer's patches, mesenteric lymph nodes, liver, and spleen). No NPs were observed by TEM in sections of the small intestine, except for several particles in the cytoplasm of a cell from a Peyer's Patch area. The observation of NPs in Peyer's Patch suggests that the Caco-2 monolayer system is likely to underestimate the potential for oral absorption of NPs and that the model could be improved by including M-cells in co-culture.


Subject(s)
Metal Nanoparticles/toxicity , Titanium/pharmacokinetics , Titanium/toxicity , Administration, Oral , Animals , Caco-2 Cells , Humans , Intestinal Absorption , Male , Mass Spectrometry , Microscopy, Electron, Transmission , Peyer's Patches/metabolism , Rats , Rats, Sprague-Dawley
20.
J Nanosci Nanotechnol ; 14(7): 5408-14, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24758040

ABSTRACT

PbS:Cu nanocrystalline films were prepared by chemical bath at temperature of 80 degrees C and deposited on glass substrates. Different Cu-doping levels were obtained changing the volume of the Cu-reagent-solution into the PbS growing solution. X-ray diffraction (XRD) and optical absorption (OA) measurements were carried out to characterize the semiconductor. The morphological changes of the layers were analyzed using an atomic force microscopy. Diffraction X-ray spectra displayed peaks at 2 theta = (26.00, 30.07, 43.10, 51.00 and 53.48), indicating growth on the zinc blende face. The grain size determined by X-rays diffraction of the undoped samples, was found -37 nm, whereas with the doped sample was - 32-25 nm. Raman spectra reports strong band in - 133-140 cm(-1) attributed to a combination of longitudinal and transversal acoustic modes. Optical absorption, forbidden band gap energy (E(g)) shift disclose a shift in the range 1.4-2.4 eV. Gibbs free energy calculation for the Cu doping PbS is also included heading.

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