Limpeza da superfície de corte de rebolos por um sistema de ar comprimido na retificação cilíndrica externa de mergulho de materiais cerâmicos refrigerados com a técnica da mínima quantidade de lubrificante (MQL)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Contribuição ao estudo da retificação abrasiva de materiais cerâmicos

Uma das principais limitações relacionadas ao processo de retificação de cerâmica é a confiabilidade do material devido aos defeitos introduzidos no processamento. A compreensão dos mecanismos envolvidos na remoção de material durante a retificação e a interação com os parâmetros de processo e microestrutura é fundamental para minimizar estes defeitos. A proposta desta revisão é apresentar os modelos de remoção de material e a forma como afetam as propriedades mecânicas da peça final.

Efeito da coesão semântica sobre a discriminação de itens emocionais em testes de memória de reconhecimento de palavras

Highly emotional itens are best remembered in emotional memory tasks than neutral items. An example of emotional item that benefits declarative memory processes are the taboo words. These words undergo from a conventional prohibition, imposed by tradition or custom. Literature suggests that the strongest recollection these words is due to emotional arousal, as well as, the fact that they form a cohesive semantic group, which is a positive additive effect. However, studies with semantic lists show that cohesion can have a negative effect of interference, impairing memory. We analyzed, in two experiments, the effect of arousal and semantic cohesion of taboo words on recognition tests, comparing with into two other word categories: semantically related and without emotional arousal (semantic category) and neutral, with low semantic relation (objects). Our results indicate that cohesion has interfered whith the performance of the test by increasing the number of false alarms. This effect was strongly observed in the semantic category of words in both experiments, but also in the neutral and taboo words, when both were explicitly considered as semantic categories through the instruction of the test in Experiment 2. Despite the impairment induced by semantic cohesion in both experiments, the taboo words were more discriminated than others, and this result agrees with the indication of the emotional arousal as the main factor for the best recollection of emotional items in memory tests

Avaliação do comportamento em fadiga de juntas estruturais de ligas de Al2024T3 coladas com adesivo epóxi

Ligas de alumínio são extensamente usadas em partes aeronáuticas devido às boas propriedades mecânicas e baixa densidade. Estas partes devem ser unidas para formar conjuntos maiores. Uma junta estrutural é definida como um segmento de estrutura que provê um meio de transferir carga de um elemento estrutural para outro. A maioria das juntas aeronáuticas é mecanicamente fixada com múltiplos prendedores (parafusos ou rebites). Estas juntas apresentam uma alta concentração de tensões ao redor do prendedor, porque a transferência de carga entre elementos da junta acontece em uma fração da área disponível. Por outro lado, as cargas aplicadas em juntas adesivas são distribuídas sobre toda a área colada e reduz os pontos de concentração de tensão. Juntas são a fonte mais comum de falhas estruturais em aeronaves e quase todos os reparos envolvem juntas. Portanto, é importante entender todos os aspectos de projeto e análise de juntas. O objetivo deste trabalho é comparar estaticamente juntas estruturais de ligas de Al2024-T3 em três condições: juntas mecanicamente rebitadas, juntas coladas e uma configuração híbrida rebitada e colada. Foi usada a norma NASM 1312-4 para confecção dos corpos-de-prova. Além disso, foram conduzidos testes de fadiga, sob amplitude de carregamento constante e razão de tensão igual a 0,1 para avaliar a eficiência dos elementos estruturais durante sua vida em serviço. Os resultados mostraram que a configuração híbrida apresenta maior resistência estática e uma vida em fadiga superior à configuração colada.

Síntese, caracterização e aplicação de MCM-41 funcionalizado com diisopropilamina no processo de adsorção do dióxido de carbono

Emissions of CO2 in the atmosphere have increased successively by various mechanisms caused by human action, especially as fossil fuel combustion and industrial chemical processes. This leads to the increase in average temperature in the atmosphere, which we call global warming. The search for new technologies to minimize environmental impacts arising from this phenomenon has been investigated. The capture of CO2 is one of the alternatives that can help reduce emis ions of greenhouse gases. The CO2 can be captured through the process of selective adsorption using adsorbents for this purpose. Were synthesized by hydrothermal method, materials of the type MCM-41 and Al-MCM-41 in the molar ratio Si / Al equal to 50. The synthesis of gels were prepared from a source of silicon, sodium, water and aluminum in the case of Al-MCM-41. The period of synthesis of the materials was 5 days in autoclave at 100°C. After that time materials were filtered, washed and dried in greenhouse at 100 º C for 4 hours and then calcined at 450 º C. Then the calcined material was functionalized with the Di-isopropylamine (DIPA) by the method of wet impregnation. We used 0.5 g of material mesopores to 3.5 mL of DIPA. The materials were functionalized in a closed container for 24 hours, and after this period were dried at brackground temperature for 2 hours. Were subsequently subjected to heat treatment at 250°C for 1 hour. These materials were used for the adsorption of CO2 and were characterized by XRD, FT-IR, BET / BJH, SEM, EDX and TG / DTG. Tests of adsorption of CO2 was carried out under the following conditions: 100 mg of adsorbent, temperature of 75°C under flow of 100 mL/min of CO2 for 2 hours. The desorption of CO2 was carried out by thermogravimetry from ambient temperature to 900ºC under flow of 25 mL min of He and a ratio of 10ºC/min. The difratogramas X-ray for the synthesized samples showed the characteristic peaks of MCM-41, showing that the structure of it was obtained. For samples functionalized there was a decrease of the intensities of these peaks, with a consequent reduction in the structural ordering of the material. However, the structure was preserved mesopores. The adsorption tests showed that the functionalized MCM-41 is presented as a material promising adsorbent, for CO2 capture, with a loss of mass on the desorption CO2 of 7,52%, while that in Al-MCM- 41 functionalized showed no such loss

Síntese e caracterização de materiais nanoporosos para pirólise catalítica de óleos pesados

The present work reports the study of nanoporous structures, aiming at their use in research directed to the current demand of the petroleum industry to value heavy oil. Initially, two ways were chosen for the synthesis of porous structures from the molecular sieves of type Si-MCM-41. In the first way, the structure MCM-41 is precursory for heteroatom substitutes of silicon, generating catalyst of the type Al-MCM-41 from two different methods of incorporation of the metal. This variation of the incorporation method of Aluminum in the structure of Si-MCM-41 was carried out through the conventional procedure, where the aluminum source was incorporated to the gel of synthesis, and the procedure post-synthesis, where the Aluminum source was incorporated in catalyst after the synthesis of Si-MCM-41. In the second way, the MCM-41 acts as a support for growth of nanocrystals of zeolite embedded in their mesoporous, resulting in hybrid MCM-41/ZSM-5 catalyst. A comparative analysis was carried through characterizations by XRD, FTIR, measures of acidity through n-butylamine adsorption for TGA, SEM-XRF and N2 adsorption. Also crystalline aluminosilicate with zeolitic structure MFI of type ZSM-5 was synthesized without using organic templates. Methodologies to the preparation of these materials are related by literature using conventionally reactants that supply oxides of necessary silicon and aluminum, as well as a template agent, and in some cases co-template. The search for new routes of preparation for the ZSM-5 aimed at, above all, the optimization of the same as for the time and the temperature of synthesis, and mainly the elimination of the use of organic templates, that are material of high cost and generally very toxic. The current study is based on the use of the H2O and Na+ cations playing the role of structural template and charge compensation in the structure. Characterizations by XRD, FTIR, SEM-XRF and N2 adsorption were also conducted for this material in order to compare the samples of ZSM-5 synthesized in the absence of template and those used industrially and synthesized using structuring

Síntese e caracterização da peneira molecular MCM-41 contendo terras raras na dessulfurização, utilizando tiofeno como molécula sonda

Mesoporous molecular sieves of MCM-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, mesoporous molecular sieves MCM-41 were modified with different rare earth ions (La, Eu e Yb) for the obtaining nanostrutured materials with catalytic properties. The catalysts were synthesized by the hydrothermal method at 100oC for 120 h, presenting, all the samples, in the gel of synthesis molar ratio Si/Ln = 50. The obtained materials after calcination at 500oC for 2 h were characterized by XRD, surface area BET, TG/DTG, FTIR, and hydrothermal stability at 700ºC. The XRD analysis of the catalysts indicated that the materials containing rare earth presented characteristic hexagonal structure of the mesoporous materials of the type MCM-41. The TG curves showed that the decomposition of the structural template occurs in the materials at temperatures lower than 500oC. The samples presented variations as the specific superficial area, average diameter of pores and thickness of the silica wall, as a function of the nature of the rare earth impregnated in the mesoporous material. Hydrotermal stability was evaluated through the exposition of the materials to water vapour at 700°C. The thiophene adsorptions reach a maximum at 80% of conversion and incorporation of the rare earths showed influence in the process. Adsorption capacity followed the sequence: Yb-MCM-41 < La-MCM-41 < Eu-MCM-41 < MCM-41

Obtenção de diesel verde por craqueamento termocatalítico de óleo de buriti (Mauritia flexuosa L.) sobre materiais nanoestruturados do tipo LaSBA-15

In order to obtain a biofuel similar to mineral diesel, lanthanum-incorporated SBA- 15 nanostructured materials, LaSBA-15(pH), with different Si/La molar ratios (75, 50, 25), were synthesized in a two-steps hydrothermal procedure, with pH-adjusting of the synthesis gel at 6, and were used like catalytic solids in the buriti oil thermal catalytic cracking. These solids were characterized by X-ray fluorescence (XRF), powder X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), infrared spectroscopy (FTIR), nitrogen porosimetry and ethanol dehydration, aiming to active sites identify. Taken together, the analyses indicated that the synthesis method has employed to obtain materials highly ordered mesostructures with large average pore sizes and high surface area, besides suggested that the lanthanum was incorporated in the SBA-15 both into the framework as well as within the mesopores. Catalytic dehydration of ethanol over the LaSBA-15(pH) products has shown that they have weak Lewis acid and basic functionalities, indicative of the presence of lanthanum oxide in these samples, especially on the La75SBA-15(pH) sample, which has presented the highest selectivity to ethylene. The buriti oil thermal and thermal catalytic cracking, realized from the room temperature to 450 ºC in a simple distillation system, has allowed obtaining two liquid fractions, each consisting of two phases, one aqueous and another organic, organic liquid (OL). The OL obtained from first fractions has shown high acid index, even in the thermal catalytic process. One the other hand, OL coming from second ones, called green diesel (GD), have presented low acid index, particularly that one obtained from the thermal catalytic process realized over LaSBA-15(pH) samples. The acid sites presence in these samples, associated to their large average pore sizes and high surface areas, have allowed them, especially the La75SBA-15(pH), to present deoxygenating activity in the buriti oil thermal catalytic cracking, providing an oxygenates content reduction, particularly carboxylic acids, in the GD. Furthermore, the GD comes from the second liquid fraction obtained in the buriti oil thermal catalytic cracking over this latest solid sample has shown hydrocarbons composition and physic-chemical properties similar to that mineral diesel, beyond sulfur content low

Craqueamento térmico e termocatalítico do óleo de girassol (Hellianthus annus L.) sobre materiais micro e mesoporosos

Microporous materials zeolite type Beta and mesoporous type MCM-41 and AlMCM-41 were synthesized hydrothermally and characterized by methods of X-ray diffraction, Fourier transform infrared, scanning electron microscopy, surface acidity, nitrogen adsorption, thermal analysis TG / DTG. Also we performed a kinetic study of sunflower oil on micro and mesoporous catalysts. The microporous material zeolite beta showed a lower crystallinity due to the existence of smaller crystals and a larger number of structural defects. As for the mesoporous materials MCM-41 and AlMCM-41 samples showed formation of hexagonal one-dimensional structure. The study of kinetic behavior of sunflower oil with zeolite beta catalysts, AlMCM-41 and MCM-41 showed a lower activation energy in front of the energy of pure sunflower oil, mainly zeolite beta. In the thermal cracking and thermocatalytic of sunflower oil were obtained two liquid fractions containing an aqueous phase and another organic - organic liquid fraction (FLO). The FLO first collected in both the thermal cracking as the thermocatalytic, showed very high level of acidity, performed characterizations of physicochemical properties of the second fraction in accordance with the specifications of the ANP. The second FLO thermocatalytic collected in cracking of sunflower oil presented results in the range of diesel oil, introducing himself as a promising alternative for use as biofuel liquid similar to diesel, either instead or mixed with it

Degradação térmica e catalítica do resíduo atmosférico de petróleo (RAT), utilizando materiais nanoestruturados do tipo SBA-15

In this work were synthesized and characterized the materials mesoporous SBA-15 and Al- SBA-15, Si / Al = 25, 50 and 75, discovered by researchers at the University of California- Santa Barbara, USA, with pore diameters ranging from 2 to 30 nm and wall thickness from 3.1 to 6.4 nm, making these promising materials in the field of catalysis, particularly for petroleum refining (catalytic cracking), as their mesopores facilitate access of the molecules constituting the oil to active sites, thereby increasing the production of hydrocarbons in the range of light and medium. To verify that the materials used as catalysts were successfully synthesized, they were characterized using techniques of X-ray diffraction (XRD), absorption spectroscopy in the infrared Fourier transform (FT-IR) and adsorption nitrogen (BET). Aiming to check the catalytic activity thereof, a sample of atmospheric residue oil (ATR) from the pole Guamaré-RN was performed the process by means of thermogravimetry and thermal degradation of catalytic residue. Upon the curves, it was observed a reduction in the onset temperature of the decomposition process of catalytic ATR. For the kinetic model proposed by Flynn-Wall yielded some parameters to determine the apparent activation energy of decomposition, being shown the efficiency of mesoporous materials, since there was a decrease in the activation energy for the reactions using catalysts. The ATR was also subjected to pyrolysis process using a pyrolyzer with gas chromatography coupled to a mass spectrometer. Through the chromatograms obtained, there was an increase in the yield of the compounds in the range of gasoline and diesel from the catalytic pyrolysis, with emphasis on Al-SBA-15 (Si / Al = 25), which showed a percentage higher than the other catalysts. These results are due to the fact that the synthesized materials exhibit specific properties for application in the process of pyrolysis of complex molecules and high molecular weight as constituents of the ATR

Síntese e caracterização de zeólita beta hierarquizada e materiais híbridos micro-mesoporosos aplicados no craqueamento de PEAD

A catalyst of great interest to the scientific community tries to unite the structure of ordered pore diameter from mesoporous materials with the properties of stability and acid activity to microporous zeolites. Thus a large number of materials was developed in the past decades, which although being reported as zeolites intrinsically they fail to comply with some relevant characteristics to zeolites, and recently were named zeolitic materials of high accessibility. Among the various synthesis strategies employed, the present research approaches the synthesis methods of crystallization of silanized protozeolitic units and the method of protozeolitic units molded around surfactant micelles, in order for get materials defined as hierarchical zeolites and micro-mesoporous hybrid materials, respectively. As goal BEA/MCM-41 hybrid catalysts with bimodal pore structure formed by nuclei of zeolite Beta and cationic surfactant cetyltrimethylammonium were developed. As also was successfully synthesized the hierarchical Beta zeolite having a secondary porosity, in addition to the typical and uniform zeolite micropores. Both catalysts were applied in reactions of catalytic cracking of high density polyethylene (HDPE), to evaluate its properties in catalytic activity, aiming at the recycling of waste plastics to obtain high value-added raw materials and fuels. The BEA/MCM-41 hybrid materials with 0 days of pre-crystallization did not show enough properties for use in catalytic cracking reactions, but they showed superior catalytic properties compared to those ordered mesoporous materials of Al-MCM-41 type. The structure of Beta zeolite with hierarchical porosity leads the accessibility of HDPE bulky molecules to active centers, due to high external area. And provides higher conversion to hydrocarbons in the gasoline range, especially olefins which have great interest in the petrochemical industry

Estudo de materiais mesoporosos funcionalizados com diferentes aminas para captura do dióxido de carbono através do processo de adsorção

Intensive use of machinery and engines burning fuel dumps into the atmosphere huge amounts of carbon dioxide (CO2), causing the intensification of the greenhouse effect. Climate changes that are occurring in the world are directly related to emissions of greenhouse gases, mainly CO2, gases, mainly due to the excessive use of fossil fuels. The search for new technologies to minimize the environmental impacts of this phenomenon has been investigated. Sequestration of CO2 is one of the alternatives that can help minimize greenhouse gas emissions. The CO2 can be captured by the post-combustion technology, by adsorption using adsorbents selective for this purpose. With this objective, were synthesized by hydrothermal method at 100 °C, the type mesoporous materials MCM - 41 and SBA-15. After the synthesis, the materials were submitted to a calcination step and subsequently functionalized with different amines (APTES, MEA, DEA and PEI) through reflux method. The samples functionalized with amines were tested for adsorption of CO2 in order to evaluate their adsorption capacities as well, were subjected to various analyzes of characterization in order to assess the efficiency of the method used for functionalization with amines. The physic-chemical techniques were used: X- ray diffraction (XRD), nitrogen adsorption and desorption (BET/BJH), scanning electron microscopy (SEM), transmission electron microscopy (TEM), CNH Analysis, Thermogravimetry (TG/DTG) and photoelectron spectroscopy X-ray (XPS). The CO2 adsorption experiments were carried out under the following conditions: 100 mg of adsorbent, at 25 °C under a flow of 100 ml/min of CO2, atmospheric pressure and the adsorption variation in time 10-210 min. The X-ray diffraction with the transmission electron micrographs for the samples synthesized and functionalized, MCM-41 and SBA-15 showed characteristic peaks of hexagonal mesoporous structure formation, showing the structure thereof was obtained. The method used was efficient reflux according to XPS and elemental analysis, which showed the presence of amines in the starting materials. The functionalized SBA -15 samples were those that had potential as best adsorbent for CO2 capture when compared with samples of MCM-41, obtaining the maximum adsorption capacity for SBA-15-P sample

Avaliação das propriedades físico-químicas de sistemas a base de carboximetilcelulose e poli (N-isopropilacrilamida) em soluções aquosas para aplicação na indústria do petróleo

Sustainable development is a major challenge in the oil industry and has aroused growing interest in research to obtain materials from renewable sources. Carboxymethylcellulose (CMC) is a polysaccharide derived from cellulose and becomes attractive because it is water-soluble, renewable, biodegradable and inexpensive, as well as may be chemically modified to gain new properties. Among the derivatives of carboxymethylcellulose, systems have been developed to induce stimuli-responsive properties and extend the applicability of multiple-responsive materials. Although these new materials have been the subject of study, understanding of their physicochemical properties, such as viscosity, solubility and particle size as a function of pH and temperature, is still very limited. This study describes systems of physical blends and copolymers based on carboxymethylcellulose and poly (N-isopropylacrylamide) (PNIPAM), with different feed percentage compositions of the reaction (25CMC, 50CMC e 75CMC), in aqueous solution. The chemical structure of the polymers was investigated by infrared and CHN elementary analysis. The physical blends were analyzed by rheology and the copolymers by UV-visible spectroscopy, small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and zeta potential. CMC and copolymer were assessed as scale inhibitors of calcium carbonate (CaCO3) using dynamic tube blocking tests and chemical compatibility tests, as well as scanning electron microscopy (SEM). Thermothickening behavior was observed for the 50 % CMC_50 % PNIPAM and 25 % CMC_75 % PNIPAM physical blends in aqueous solution at concentrations of 6 and 2 g/L, respectively, depending on polymer concentration and composition. For the copolymers, the increase in temperature and amount of PNIPAM favored polymer-polymer interactions through hydrophobic groups, resulting in increased turbidity of polymer solutions. Particle size decreased with the rise in copolymer PNIPAM content as a function of pH (3-12), at 25 °C. Larger amounts of CMC result in a stronger effect of pH on particle size, indicating pH-responsive behavior. Thus, 25CMC was not affected by the change in pH, exhibiting similar behavior to PNIPAM. In addition, the presence of acidic or basic additives influenced particle size, which was smaller in the presence of the additives than in distilled water. The results of zeta potential also showed greater variation for polymers in distilled water than in the presence of acids and bases. The lower critical solution temperature (LCST) of PNIPAM determined by DLS corroborated the value obtained by UV-visible spectroscopy. SAXS data for PNIPAM and 50CMC indicated phase transition when the temperature increased from 32 to 34 °C. A reduction in or absence of electrostatic properties was observed as a function of increased PNIPAM in copolymer composition. Assessment of samples as scale inhibitors showed that CMC performed better than the copolymers. This was attributed to the higher charge density present in CMC. The SEM micrographs confirmed morphological changes in the CaCO3 crystals, demonstrating the scale inhibiting potential of these polymers

Influência da técnica de fabricação e dos materiais sobre o ajuste da interface pilar/implante em infraestruturas implantossuportadas

The aim of this study was to compare the misfit vertical, horizontal and passivity of zirconia and cobalt-chromium frameworks fabricated for CAD / CAM technology and conventional method of casting. Sixteen frameworks in one-piece, were obtained from a metallic matrix containing three Brånemark compatible implants with regular platform (Titamax Cortical Ti, Neodent). Eight frameworks were fabricated by CAD / CAM system (NeoShape, Neodent): four in zirconia (ZirCAD) and four cobalt-chromium (CoCrcad). Eight other frameworks were obtained by conventional casting method: four cobalt-chromium with UCLA abutment premachined Co-Cr (CoCrUCci) and four cobalt-chromium with UCLA abutment castable (CoCrUCc). The fit vertical, horizontal and passivity by one-screw test were measured using scanning electron microscopy with magnification of 250x. Initially evaluated the passivity by one-screw test and subsequently to assess the vertical and horizontal misfit, tightened all the screws with a torque of 20 Ncm. Mean, standard deviation, minimum and maximum values were calculated for each group. Measurements of horizontal misfit were transformed into cumulative frequency for categorization of the variable and the group later comparison groups. To evaluate the existence of quantitative differences between the groups tested for vertical misfit and passivity, we used the Kruskal-Wallis test. The Mann-Whitney test was used to compare group to group statistical differences (p <0.05). Were observed the respective mean and standard deviation for vertical misfit and passivity in micrometers: ZirCAD (5.9 ± 3.6, 107.2 ± 36), CoCrcad (1.2 ± 2.2, 107.5 ± 26 ), CoCrUCci (11.8 ± 9.8, 124.7 ± 74), CoCrUCc (12.9 ± 11.0, 108.8 ± 85). There were statistical differences in measures of vertical misfit (p = 0.000). The Mann-Whitney test revealed statistical differences (p <0.05) between all groups except between CoCrUCci and CoCrUCc (p = 0.619). No statistical difference was observed for the passivity. In relation to the horizontal misfit groups ZirCAD and CoCrcad did not show best values in relation to CoCrUCci and CoCrUCc. Based on the results it can be concluded that frameworks fabricated by CAD / CAM technology had better values of vertical fit than those manufactured by the casting method, nevertheless, the passivity was not influenced by manufacturing technique and material used. The horizontal fit obtained by frameworks manufactured by CAD / CAM was not superior to those manufactured by casting. A lower variability in vertical adjustment and passivity was observed when frameworks were fabricated by CAD / CAM technology

Influência do pré-aquecimento na adaptação marginal de dois materiais seladores de fóssulas e fissuras, analisada através de tomografia de coerência ótica

Among the non-invasive techniques employed in the prevention of caries highlights the sealing pits and fissures which is a conservative maneuver, in order to obliterate them to protect them from attack acid bacteria. Influenced by the studies of pre-heating composite resin, which has experienced great improvement in some of their physical properties, this study aimed to evaluate in vitro the superficial and internal marginal adaptation of different materials and sealants in pre-heating or not. A total of 40 extracted human third molars (n=10) that had their occlusal surfaces prepared to receive sealant. We tested two types of sealing materials: resin sealant (Fluoroshield) and low-viscosity resin (Permaflo), where 50% of previously received heated material and the other half received sealant material at room temperature. All samples were subjected to thermal cycling and pH, simulating a cariogenic oral environment, and later were analyzed appliance OCT (optical coherence tomography). The images obtained alterations were recorded and analyzed statistically. Change was considered as the emergence of bubbles, gaps and cracks in the sealant. Comparisons of the same material, assessing the fact that it is not sealed or preheated material, as well as comparisons between different materials subjected to the same temperature were carried out. The nonparametric Tukey test was used (p < 0,05). The results showed that there was statistically significant difference between both the materials analyzed, as between the situations in which the sealant material was submitted (preheated or not). On the issue of marginal adaptation and internal surface, seen through Optical coherence tomography, may suggest that there is a difference between the use of one type or another of the sealing material analyzed, with superiority attributed to resin Permaflo compared to sealant Fluroshield, telling is the same for the different techniques used