Síntese e caracterização de peneiras moleculares mesoporosas do tipo MCM-41 e AlMCM-41 a partir de fontes alternativas de sílica e de alumínio

The mesoporous molecular sieves of MCM-41 and AlMCM-41 type are considered as promising support for metal in the refining processes of petroleum-based materials as catalysts and adsorbents for environmental protection. In this work the molecular sieves MCM-41 and AlMCM-41 were synthesized by replacing the source of silica conventionally used, for quartz, an alternative and abundant, and the use of waste from the production of diatomaceous earth, an aluminum-silicate, as a source aluminum, due to abundant reserves of diatomaceous earth in the state of Rio Grande do Norte in the city of Ceará-Mirim, with the objective of producing high-value materials that have similar characteristics to traditional commercial catalysts in the market. These materials were synthesized by the method of hydrothermal synthesis at 100 º C for 7 days and subjected to calcination at 500 º C for 2 hours under flow of nitrogen and air. The molecular sieves were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA) and thermogravimetric analysis (TG), adsorption of N2 (BET and BJH methods), spectroscopy in the infra red (FTIR), microscopy scanning electron (SEM) and transmission electron microscopy (TEM). The analysis indicated that the synthesized materials showed characteristic hexagonal structure of mesopores materials with high specific surface area and sort and narrow distribution of size of pores

Síntese de catalisadores do tipo LaNixFe1-xO3 como precursores catalíticos para reação oxidação parcial do metano

Nickel-bases catalysts have been used in several reform reactions, such as in the partial oxidation of methane to obtain H2 or syngas (H2 + CO). High levels of conversion are usually obtained using this family of catalysts, however, their deactivation resulting from carbon deposition still remains a challenge. Different approaches have been tested aiming at minimizing this difficulty, including the production of perovskites and related structures using modern synthesis methods capable of producing low cost materials with controlled microstructural characteristics at industrial scale. To establish grounds for comparison, in the present study LaNixFe1-xO3 (x=0, 0.3 or 0.7) perovskites were prepared following the Pechini method and by microwave assisted self-combustion. All samples were sub sequently calcined at 900 °C to obtain the target phase. The resulting ceramic powders were characterized by thermogravimetric analysis, infrared spectroscopy, X ray diffraction, specific area and temperature programmed reduction tests. Calcined samples were also used in the partial oxidation reaction of methane to evaluate the level of conversion, selectivity and carbon deposition. The results showed that the calcined samples were crystalline and the target phase was formed regardless of the synthesis method. According to results obtained by Rietveld refinement, we observed the formation of 70.0% of LaNi0.3Fe0.7O3 and 30.0% of La2O3 for samples LN3F7-900- P, LN3F7-900-M and 41,6% of LaNi0.7Fe0.3O3, 30.7% of La2NiO4 and 27.7% of La2O3 for samples LN7F3-900-P and LN7F3-900-M.Temperature-programmed profiles of the LaNiO3 sample revealed the presence of a peak around 510 °C, whereas the LaFeO3 sample depicted a peak above 1000°C. The highest l evel of methane conversion was obtained for LaNiO3 synthesized by the Pechini method. Overall, catalysts prepared by the Pechini method depicted better conversion levels compared to those produced by microwave assisted self-combustion

Preparação e caracterização de catalisadores à base de titânio suportado em MCM-41 para produção de compostos oxigenados através da pirólise catalítica do capim elefante

In recent years, the area of advanced materials has been considerably, especially when it comes to materials for industrial use, such as is the case with structured porosity of catalysts suitable for catalytic processes. The use of catalysts combined with the fast pyrolysis process is an alternative to the oxygenate production of high added value, because, in addition to increasing the yield and quality of products, allows you to manipulate the selectivity to a product of interest, and therefore allows greater control over the characteristics of the final product. Based on these arguments, in this work were prepared titanium catalysts supported on MCM-41 for use in catalytic pyrolysis of biomass, called elephant grass. The reactions of pyrolysis of biomass were performed in a micro pyrolyzer, Py-5200, coupled to GC / MS, the company CDS Corporation, headquartered in the United States. The catalysts Ti-MCM-41 in different molar ratios were characterized by XRD, TG / DTG, FT-IR, SEM, XRF, UV-visible adsorption of nitrogen and the distribution of particle diameter and specific surface area measurement by the BET method. From the catalytic tests it was observed that the catalysts synthesized showed good results for the pyrolysis reaction.The main products were obtained a higher yield of aldehydes, ketones and furan. It was observed that the best reactivity is a direct function of the ratio Si/Ti, nature and concentration of the active species on mesoporous supports. Among the catalysts Ti-MCM-41 (molar ratio Si / Ti = 25 and 50), the ratio Si / Ti = 25 (400 ° C and 600 ° C) favored the cracking of oxygenates such as acids , aldehydes, ketones, furans and esters. Already the sample ratio Si / Ti = 50 had the highest yield of aromatic oxygenates

Propriedade fotoluminescente da ZrO2: Tb+3, Eu+3, Tm+3 obtida pelo método de polimerização de complexos

Recent studies are investigating a new class of inorganic materials which arise as a promising option for high performance applications in the field of photoluminescence. Highlight for rare earth (TR +3 ) doped, which have a high luminous efficiency, long decay time and being able to emit radiation in the visible range, specific to each element. In this study, we synthesized ZrO2: Tb +3 , Eu +3 , Tm +3 nanoparticles complex polymerization method (CPM). We investigated the influences caused by the heat treatment temperature and the content of dopants in zirconia photoluminescent behavior. The particles were calcined at temperature of 400, 500 and 600 ° C for two hours and ranged in concentration of dopants 1, 2, 4 and 8 mol% TR +3 . The samples were characterized by thermal analysis, X-ray diffraction, photoluminescence of measurements and uv-visible of spectroscopies. The results of X-ray diffraction confirmed the formation of the tetragonal and cubic phases in accordance with the content of dopants. The photoluminescence spectra show emission in the region corresponding simultaneous to blue (450 nm), green (550 nm) and red (615 nm). According to the results, ZrO2 particles co-doped with rare earth ions is a promising material white emission with a potential application in the field of photoluminescence

Reforma a seco de metano com catalisadores Ni/MCM-41 sintetizados a partir de fontes alternativas de sílica

The production of synthesis gas has received renewed attention due to demand for renewable energies to reduce the emissions of gases responsible for enhanced greenhouse effect. This work was carried out in order to synthesize, characterize and evaluate the implementation of nickel catalysts on MCM-41 in dry reforming reactions of methane. The mesoporous molecular sieves were synthesized using as silica sources the tetraethyl orthosilicate (TEOS) and residual glass powder (PV). The sieves were impregnated with 10% nickel to obtain the metallic catalysts (Ni/MCM-41). These materials were calcined and characterized by Thermogravimetric Analysis (TG), Infrared spectroscopy (FTIR), X-ray Diffraction (XRD), Temperature-Programmed Reduction (TPR) and N2 Adsorption/Desorption isotherms (BET/BJH). The catalytic properties of the samples were evaluated in methane dry reforming with CO2 in order to produce synthesis gas to be used in the petrochemical industry. The materials characterized showed hexagonal structure characteristic of mesoporous material MCM-41 type, being maintained after impregnation with nickel. The samples presented variations in the specific surface area, average volume and diameter of pores based on the type of interaction between the nickel and the mesoporous support. The result of the the catalytic tests showed conversions about 91% CO2, 86% CH4, yelds about 85% CO and 81% H2 to Ni/MCM-41_TEOS_C, and conversions about 87% CO2, 82% CH4, yelds about 70% CO and 59% H2 to Ni/MCM-41_PV_C. The similar performance confirms that the TEOS can be replaced by a less noble materials

Degradacao termica e catalitica da borra oleosa de Petroleo com materiais nanoestruturados al-mcm-41 e AL-SBA-15

Aiming to reduce and reuse waste oil from oily sludge generated in large volumes by the oil industry, types of nanostructured materials Al-MCM-41 and Al-SBA-15, with ratios of Si / Al = 50, were synthesized , and calcined solids used as catalysts in the degradation of oily sludge thermocatalytic oil from oilfield Canto do Amaro, in the state of Rio Grande do Norte. Samples of nanostructured materials were characterized by thermogravimetric analysis (TG / DTG), X-ray diffraction (XRD), scanning electron microscopy (SEM), absorption spectroscopy in the infrared Fourier transform (FT-IR) and adsorption nitrogen (BET). The characterization showed that the synthesized materials resulted in a catalyst nanostructure, and ordered pore diameter and surface area according to existing literature. The oily sludge sample was characterized by determining the API gravity and sulfur content and SARA analysis (saturates, aromatics, resins and asphaltenes). The results showed a material equivalent to the average oil with API gravity of 26.1, a low sulfur content and considerable amount of resins and asphaltenes, presented above in the literature. The thermal and catalytic degradation of the oily sludge oil was performed from room temperature to 870 ° C in the ratios of heating of 5, 10 and 20 ° C min-1. The curves generated by TG / DTG showed a more accelerated degradation of oily sludge when it introduced the nanostructured materials. These results were confirmed by activation energy calculated by the method of Flynn-Wall, in the presence of catalysts reduced energy, in particular in the range of cracking, showing the process efficiency, mainly for extraction of lightweight materials of composition of oily sludge, such as diesel and gasoline

Estudo de efeitos de um extrato de Arctium lappa (Bardana) na marcação dos constituintes sangüíneos com Tecnécio-99m, na biodisponibilidade do radiofármaco pertecnatato de sódio e na morfologia de hemácias de ratos Wistar

Radionuclides have been used in Nuclear Medicine for diagnostic and treatment. In basic research, cellular and molecular structures are labeled with technetium-99m (99mTc) and used as radiobiocomplexes. Some natural or synthetic drugs are capable to alter the labeling of blood constituents with 99mTc, as well as in the biodistribution of radiobiocomplexes. Arctium lappa (Bardana) has been used to treat inflammatory processes. The aim of this work was to evaluate the effects of an extract of Bardana on the labeling of blood constituents with 99mTc, on the morphology of red blood cells, on the perimeter/area ratio of red blood cells and on the biodistribution of radiophamaceutical sodium pertechnetate in Wistar rats. Extract of Bardana was capable to alter the labeling of cellular compartment with 99mTc. Plasma and cellular proteins did not present alteration on the percentage of radioactivity (%ATI). Extract of Bardana was also capable to alter the morphology and the perimeter/area ratio of red blood cells. On the biodistribution of sodium pertechnetate in animals treated with the extract of Bardana, it was observed a small and significant uptake in liver, tooth and tongue, and a high and a significant uptake in stomach, lung and testis (p<0.05). In conclusion, these findings could be justified due to the effects of some chemical compounds in the Bardana extract. This study was a multidisciplinary experimental research. It was developed with the contribution of the different Departments and Services of the Hospital Universitário Pedro Ernesto of the Universidade Estadual do Rio de Janeiro

Danos da morte súbita dos citros sobre a produção de laranja

A Morte Súbita dos Citros (MSC) afeta laranjeiras doces (Citrus sinensis) e algumas tangerineiras (Citrus reticulata) enxertadas em limoeiro 'Cravo' (Citrus limonia) no norte do Estado de São Paulo e sul do Triângulo Mineiro. O progresso da doença nos pomares têm causado grande preocupação para o agronegócio citrícola. Para caracterizar e quantificar os danos causados pela MSC, a produção de frutos (peso total e número de frutos por planta e tamanho dos frutos) foi avaliada em quatro talhões para cada combinação variedade ('Hamlin', 'Pêra', 'Natal' e 'Valência') / classe de idade (três a cinco anos, seis a dez anos e 11 a 15 anos). em cada talhão, as plantas foram classificadas de acordo com a severidade de MSC (0 = sadia, 1 = sintomas iniciais e 2 = sintomas severos). Para cada nível de severidade foram colhidas dez plantas escolhidas ao acaso. Os danos foram caracterizados pela redução do peso total de frutos por planta (28% e 50% para o nível 1 e 2, respectivamente), do número total de frutos por planta (12% e 26% para o nível 1 e 2, respectivamente) e do tamanho do fruto (22% e 41% para nível 1 e 2, respectivamente). As variedades de laranja não diferiram em relação à porcentagem de redução para todas as variáveis de produção avaliadas. As plantas mais jovens tiveram a maior redução no número total de frutos por planta e as plantas com mais de cinco anos de idade tiveram as maiores reduções no tamanho dos frutos. As classes de idade não diferiram na porcentagem de redução do peso total de frutos por planta.

Fontes de proteína e carboidratos para cães e gatos

O mercado de alimentos para cães e gatos absorve importante quantidade de proteínas e carboidratos, apesar disso poucos estudos existem sobre digestibilidade e energia metabolizável destes ingredientes. Arroz e milho têm sido considerados as melhores fontes de amido, mas demonstra-se que o sorgo é igualmente bem digerido por cães. Na interpretação dos estudos, deve-se distinguir os que empregaram farinhas ou amidos purificados dos que empregaram ingredientes moídos, como utilizado na fabricação de alimentos para animais de companhia. Além de sua digestibilidade e valor energético, amidos interferem na glicemia de cães, o que torna interessante se empregar, para animais em condições específicas, fontes de carboidrato que levem à menores respostas de glicose e insulina. Devido a elevada necessidade de proteína, ingredientes protéicos são importantes nas formulações. Proteínas de origem animal apresentam maior variação em composição química, qualidade e digestibilidade que as de origem vegetal. Farinhas de origem animal podem apresentar excesso de matéria mineral, limitando sua inclusão na fórmula, enquanto derivados protéicos vegetais apresentam diversos fatores anti-nutricionais que devem ser inativados durante seu processamento. Demonstra-se que proteínas vegetais apresentam boa digestibilidade e energia metabolizável para cães e gatos, sendo sua inclusão interessante para reduzir a matéria mineral da dieta, controlar o excesso de bases do alimento e manter adequada a digestibilidade do produto, neste sentido soja micronizada e o farelo de glúten de milho 60% se destacam em digestibilidade e teor de energia metabolizável. A farinha de vísceras de frango, dentre as proteínas de origem animal secas demonstra-se como a de melhor digestibilidade e energia metabolizável.

Progresso científico sobre nutrição de animais de companhia na primeira década do século XXI

O conhecimento científico sobre nutrição de animais de companhia tem aumentado de forma contínua, acompanhando o fenômeno visto em diversas áreas de conhecimento. Na última década, têm-se prioritariamente pesquisas direcionadas ao uso de nutrientes na promoção de saúde, prevenção de doenças degenerativas, melhoria da qualidade de vida e aumento da expectativa de vida de cães e gatos. Este direcionamento de pesquisas é, em grande parte, explicado pela importância que cães e gatos assumiram na vida das pessoas, fazendo com que as decisões alimentares dos proprietários com seus animais se assemelhassem às que adotam para si próprios. A publicação da nova revisão do Nutrient Requirements of Dogs and Cats em 2006 foi, talvez, o avanço recente mais significativo, trazendo novo entendimento sobre necessidades energéticas e de nutrientes nas diferentes fases de desenvolvimento e estados fisiológicos. Apesar destes avanços, ainda são necessárias pesquisas na área de caracterização físico-química e de utilização dos ingredientes, efeitos do processo de extrusão e mesmo de necessidades nutricionais, que conta com uma base pequena de artigos disponíveis, a maioria antiga. Talvez os desafios científicos mais importantes em nutrição de cães e gatos sejam metabolismo de carboidratos, importância da massa corporal magra na saúde, urolitíases, gerontologia, relação entre microbiota intestinal e saúde, imunonutrição e manejo nutricional em condições clínicas específicas importantes para estas espécies.

Chromatin and morphometry alterations of bovine sperm head after Percoll (TM) density gradient centrifugation

The aim of this work was to assess the morphometry and chromatin integrity of bovine sperm head after a three layers discontinuous Percoll (TM) density gradient centrifugation. Frozen semen doses were obtained from six bulls of different breeds, including three taurine and three Zebu animals. Three ejaculates per bull were evaluated. The semen doses were thawed and two smears were made from each sample before (control) and after the Percoll (TM) centrifugation (Percoll (TM) group). The smears were stained with toluidine blue and grayscale digital images were captured and processed in Scilab environment software. It was observed that chromatin heterogeneity was reduced (P<0.05) and chromatin decondensation was increased (P<0.05) after the Percollm treatment utilized. In addition, it was observed that sperm head length was higher (P<0.05) and the side symmetry was lower (P<0.05) in centrifuged sperm cells. When analyzed separately by subspecies, it was observed that the decrease (P<0.05) in chromatin heterogeneity and the increase (P<0.05) in chromatin decondensation occurred in Zebu sperm heads. In addition, the length and the width:length ratio of sperm heads was affected by Percoll (TM) centrifugation in Zebu semen. In conclusion, the three layers discontinuous Percoll (TM) centrifugation increased the chromatin decondensation and the morphometric alterations of frozen-thawed bovine semen. However, the real implication of these findings in fertility rates of centrifuged sperm must be investigated. (C) 2011 Elsevier B.V. All rights reserved.

Violência contra a mulher : estudo de caso em uma instituição de ensino

The study research case with a quantitative approach and prospective data, carried out between December 2010 and February 2011 with the aim of identifying the profile of women in the study, to characterize the acts of violence in the type, frequency, location occurrence and aggressor, analyze the steps taken after the occurrence of acts of violence and the main consequences on the victims. The population consisted of 285 workers in a tertiary institution in Rio Grande do Norte. The results showed that 99 (34.74%) have between 51 to 60 years of age, 78 (27.37%) of 41 to 50 and 62 (21.75%) between 20 and 30 years, are considered color white, 162 (56.84%) have completed higher education, 171 (60.00%) and of these 97 (56.73%) reported having some post-graduate degrees, are married, 141 (49.47%) and have from zero to one child, 148 (51.93%) reside in the south of the city of Natal, 146 (51.23%) have a monthly income of three to five minimum wages, 171 (60.00%) and are mostly in the Technical Administrative Sciences 152 (53.33%), 77 (27.02%) reported having experienced violence, 60 (62.50%) episodes of verbal aggression, 26 (27.08%) of bullying , 05 (5.21%) of physical abuse and 05 (5.21%) sexual harassment; 05 (100.00%) assaults were made by the spouse or partner of the victims and co-workers is another profession were responsible for 18 (30.00%) verbal aggression, 15 (57.69%) bullying and 03 (60.00%) sexual harassment, 02 (40.00%) of victims of physical aggression and 18 (30.00 %) of verbal abused only once, 10 (38.46%) of bullying and 02 (40.00%) of sexual harassment experienced four or more times 05 (100.00%) assaults occurred at domestic and work stood out with 36 (60.00%), verbal abuse, 22 (84.62%), moral harassment and 04 (80.00%) sexual harassment, 35 (36.46%) told colleagues work and 31 (32.29%) for family and friends in 75 (78.13%) cases there was no intervention, 07 (7.29) were unable to respond if something had been done and 14 (14.58% ) have been reported intervention of these, 09 (64.29%) were taken by the heads of the victims, 26 (32.10%) did not notify the fact on the ground that no action would be taken, 62 (80.52%) felt stress , 5 (1.76%) of women turned away from work after the episode of violence, accounting for 198 days of absenteeism. It is concluded that there is a high rate of violence against women, even when they have a good socioeconomic status, and in this sense is important to establish bases of new proposals for improving control of cases of health professionals, especially nurses, to approach patients with a more investigative, and that by identifying a case of violence, be instructed about the paths to be followed for notification while providing psychological support to victims.

Carga de trabalho de enfermagem e infecções relacionadas à assistência à saúde na unidade de terapia intensiva

In recent decades, the search for quality care has been widely discussed by the institutions and health professionals. In this context, it is the nurse coordinator of the process of providing nursing staff, reflecting the commitment to quality of care. In this process, it is the appearance of Infections Related to health care and its potential association with the workload in nursing as a valuable indicator of quality of care. Thus, this research contributes to studies to characterize the demand of nursing work to promote a safe healthcare practice. This study aimed to identify the association of nursing workload with the number of cases of Ventilator-Associated Pneumonia, urinary tract infection and central venous catheter infection in the intensive care unit. This is a quantitative research approach, descriptive, cross-sectional and prospective, held at Unimed Hospital in Natal-RN. The study population consisted of all patients treated in the Intensive Care Unit, Hospital for a period of 90 consecutive days in 2011. The convenience sample was compostapelos patients admitted to the ICU during the period of data collection, a total sample of 286 patients. To perform the data analysis software were used: Statistica 6.0, SPPS (Statistical Package for Social Sciences) version 17.0 (2004) and Excel 2007. In the descriptive analysis, we used Measures of Central Tendency and Measures of Dispersion or Variability and the use of nonparametric tests. Of the 286 patients, 88 were from the ICU and 198 ICU II II. Males predominated in the ICU I (51.1%) and female ICU II (57.6%) patients in the ICU I were aged 61-80 years (39.8%) followed by greater than 80 years (39.8%). In the ICU II, most of the patients were aged 61-80 years (38.9%) and then from 41 to 60 years (24.2%). In relation to the class of TISS inlet predominant class II in the two ICUs (59.1%), followed by Class III also in the two units (34.6%). Most patients (70.6%) out of the ICUs belonging to class II TISS. In the ICU I, the average number of forms of the TISS 28 was 6, has in ICU II this value drops to 3.2 forms. The overall mean was 19.9 TISS points in ICU patients I and ICU II.the 17 points in the average hours required to provide adequate nursing care to patients in the ICU I found that is 10 , 7 hours, and the ICU II 9.2 hours. It was found that the time provided by the nursing staff were higher in ICU II, with an average of 19 hours available for nurses in this sector. In the ICU I, which showed higher need of available hours, it was found that the mean value of 12.7 available hours. It was found that only 2.4% of patients had these units Ventilator-Associated Pneumonia, 1.0% were infected central venous catheter and 1.4% of patients had urinary tract infection. Infection associated with health care occurs, on average, on the tenth day of hospitalization. In the ICU II, this average value extends to the twelfth day with an excess of 2.7 hours of nursing care while in ICU I value decays to the ninth day of hospitalization with a deficiency of 12-hour assistance. It is concluded that patients generally showed a need for classification of semi-intensive care and has been assisted in their need to load. As for his association with the Related Infections Health will assist this analysis could not be performed due to the small number of notifications in this period. It is suggested further study how other factors related to infections me a longer period of analysis