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Copyright of Agriscientia is the property of Revista AgriScientia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For the design of vessels built by GFRP laminates, an insert with a memory foam layer is proposed to reduce the spread of damage produced by the vertical impact of the ship's bottom with the sea or slamming phenomenon. Using vertical drops-weight impact machine that reproduces the energy inferred to the panel during navigation, the propagation of the damage of OoA cured prepreg panels is studied by comparing it with modified panels with insertion of viscoelastic layer. The use of acceleration data reading allows the benefits of viscoelastic modification during impact to be quantified through the developed formulation. The force, displacement, and energy returned by the panel after impact have also been quantified, which does not become intralaminar and interlaminar damage. [ABSTRACT FROM AUTHOR]

Objective: To compare the level of radicular stress and pres- sure exerted on adjacent tissues in 1.4 upper premolars with effect and without effect, vertical and axial compression splint in prefabricated posts, fiberglass and titanium vs cast noble metal (Au) and nickel chromium (NiCr) cast metal studs, cemented with self-adhesive self-conditioning resinous cement using the finite element technique. Materials and Methods: An experimental and comparative study was carried out with 8 simulated 3D models of 1.4 upper premolars. The FEMAP 11.1.2 software was used to model the mechanical design in 3D. Results: The radicular stress level is higher in the prefabricated cast Au and NiCr posts both at 360 and 180º compared to the fiberglass and titanium ones, the most representative average being in the NiCr at 360º with 104.23 Mpa and the lowest in Titanium 180º with 83.79 Mpa. The pressure exerted on adjacent tissues, in the premolars, has a higher level in prefabricated posts based on fiberglass and titanium at 180º compared to those made of noble metal and nickel-chromium, the most representative being that of smooth fiberglass at 180º with 1.43 and the low- est is the 360º NiCr with 1.30. Conclusion: The radicular stress level is higher in pre-cast Au and NiCr posts both at 360 and 180º compared to fiberglass and titanium posts, and the level of pressure exerted on adjacent tissues in the premolars has a higher level in prefabricated fiberglass and titanium bolts, both at 180º, compared to Au and NiCr [ABSTRACT FROM AUTHOR]

In this work is presented a software to predict the behavior of solar stills, in this the climate and building parameters are taken into account, this means that it is a useful tool to dimension devices, its validation is presented based on three devices built in Centro de Investigaciones de Energía Solar (CIES).Experimental values are used to validate the theoretic results yielded by the SoftDest program. To do that, statistical methods like normality analysis, correlation analysis and finding the prediction bands were applied.Experimental data were obtained from solar distillers built with metal tray, glass fiber and materials for building, respectively. Results show the accurate of theoretical results and experimental data, pointing the feasibility of the use of this software to simulate and dimension solar distillers. [ABSTRACT FROM AUTHOR]

The ablative materials are the base of the thermal protection systems for equipment and recoverable elements that, when used, are exposed to high temperatures. Generally, these materials are hard to acquire and costly, which makes difficult their application in countries such as Colombia. This research describes the acquisition and characterization of ablative composites based on a matrix of polyester resin reinforced with particulate materials (60-70% in weight) and fiberglass (5% in weight). Ceramic residues and aluminum dross finely ground (75 µm) were used as particulates, highlighting that both materials are industrial byproducts. The developed composites were put through the direct flame test to assess their ablative performance. Thus, the thermal conditions (1,600-2,000 °C) to which the nozzle of a low orbit rocket (prove type) is exposed were simulated. Complementarily, the effect of the ablative test over the cracking level and erosion (loss of weight) of the developed composites were assessed. As an indirect measure of the residual mechanic performance of the composites the hardness of the thermally affected area was determined. The gathered results are considered highly important for the production of thermic protection systems or propelling composites with raw materials of easier acquisition and lower cost in Colombia. [ABSTRACT FROM AUTHOR]

The objective of the research is to obtain a theoretical model that characterizes an optical fiber sensor. To achieve this, the change in the properties of the light rays that propagate through the core of the fiber was characterized, when the medium undergoes a fold proportional to the deformation of a set of four springs that supports the weight of a C2 vehicle (two axis). The deformation altered the angle of curvature (a) of the glass fiber, which in turn affected the propagation of light due to the presence of reflected and refracted waves. This event modified the magnitude of the transmission coefficient (T) that was evaluated in the receiver. This article presents the experimental study -under controlled conditions-, the recording, data analysis and regression to model the sensor by means of an algebraic equation. [ABSTRACT FROM AUTHOR]

In this work, the characterization of sheets of spoolable composite pipe reinforced with glass fiber with configuration [55,-55]6 is performed. For this purpose, tensile tests under static and dynamic loads are performed, according to ASTM D3039 and D3479 standards. The tests are carried out to obtain the tensile strength and the S-N curve under tensile loads. With the data obtained, a statistical adjustment is made using the Weibull distribution model and its subsequent analysis applying the fatigue models of Basquin and Wöhler, and the mode of failure of this type of material is identified. [ABSTRACT FROM AUTHOR]

Measurements of magnetic susceptibility x as a function of temperature in the range 2-300 K on polycrystalline samples of Cu2Cd1-zMnzSnSe4 magnetic semiconductor alloy system are reported. The Curie constant C increase linearly with z. The Curie-Weiss temperature θ and Néel temperature TN increase linearly with z due to a partial order change to total disorder of the Mn+2 ions in the system. In a first approximation, it can be considered that this system has typical spin glass behavior (spin glass system), which means that ions Mn+2 are somewhat disorderly way cationic network of material. [ABSTRACT FROM AUTHOR]

Copyright of La Revista Latinoamericana de Metalurgia y Materiales, RLMM is the property of Universidad Simon Bolivar, Departmento de Ciencia de los Materiales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Havana Seafront wall is constantly beaten by the inclemency of the weather. The safety of the Cuban capital patrimonial bordering constructions depends on the seafront integrity. The concrete that shapes the wall has different states of deterioration, which is why its repair and conservation is mandatory using a reinforcement material that completely eliminates the problem of corrosion. In this work the design of a new variant of the wall of the Havana Seafront reinforcement with polymers reinforced with fiberglass (GFRP) as an alternative solution to classic steel structural reinforcement. With the results of this work it is expected to get a better knowledge of the advantages of the application of the GFRP in the construction of structures exposed to aggressive environments. [ABSTRACT FROM AUTHOR]

The article presents two summaries of the bibliographic section of the Oral magazine. The first summary focuses on the effectiveness of using silver diamine fluoride (SDF) in carious lesions of temporary teeth. It is mentioned that SDF has been used in countries such as Japan, China, Brazil, and Argentina, and it has been shown to inactivate carious processes and promote tooth remineralization. However, its disadvantage is the black pigmentation in the tissues where it is applied. The second summary focuses on the use of glass fibers (GF) in current dentistry. It is highlighted that GF is versatile and used in different areas of dentistry, such as splinting dental organs, restoring teeth with endodontics, and fixed partial prosthesis. It is concluded that GF is a less invasive, cost-effective, and aesthetically pleasing option for dental treatments. [Extracted from the article]

Copyright of Revista ADM is the property of Asociacion Dental Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Iberoamericana de Ingeniería Mecánica is the property of Editorial UNED and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The influence of fiber coatings on the effectiveness of the propylene-glass copolymerization reaction has been analyzed. The mechanical properties of fiber reinforced composites depend on the effective stress transfer fiber-matrix, which is possible if the adhesion between them is strong. An alternative method to improve the adhesion is the establishment of chemical links between matrix-fiber such as in situ polymerization. The study was carried out on sandwich composite of polypropylene and fiber glass, with and without acrylic coating. Adhesion is analyzed through its influence on the mechanical properties of the composites. The copolymerization reaction acts as an effective bonding agent, when it is carried out on uncoated fibers, making this proposal technological attractive. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Facultad de Odontología. Universidad Nacional de Cuyo is the property of Universidad Nacional de Cuyo, Facultad de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Iberoamericana de Ingeniería Mecánica is the property of Editorial UNED and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper deals with the calculations of resistance and rigidity of a specialized shalow water vessel for the treatment of waste waters. It will be located in the marshy area of Cienaga de Zapata, Cuba, for this reason highly durable and resistant materials to the action of such aggressive environment are used. We are dealing with plastics and glass fiber due to the high weight in the cover the calculation is not established by Ships Registrations and therefore became necessary to carried out the complete vessel calculation with this orthotropic material. It was necessary applied the Finite Elements Method by means of a computation program. We arrived to the complete design of different parts of the vessel with this complex material. It has already been built and it is in operation. [ABSTRACT FROM AUTHOR]

The present work is the second of a compilation of two investigation researches that were carried out in order to study some physical-mechanical properties of materials made up of polymeric matrix, with different types of fillers of glass fibers and fillers from national sources; these last ones with the purpose of optimizing properties and to reduce the costs. They were carried out the rehearsals of flexure resistance, coefficient of Poisson, specific, gravity and humidity. The experimental results the same as the result exposed in the first article were processed by means of the professional package STATGRAPHICS 4.1 with which the regression equations were obtained together with the graphic representation of behavior of the properties. [ABSTRACT FROM AUTHOR]

Diverse types of solar stills are known, among those stand out the ones that use the greenhouse effect, because of the simplest and most economic procedures in obtaining distilled water. The literature reports the existence of diverse technologies and materials for the design and construction of solar stills. In the present work is shown the development of a solar still prototype, with a view to the obtention of water distilled for different uses such as water for the self-driven transport, batteries, etc. It is presented the construction and evaluation of a solar still prototype, built of glass fiber. The still operation is evaluated, being measured the daily productivity and the quality of the distilled water. It is carried out the analysis of the results obtained in the evaluation and an economic valuation of the possible use of this equipment. [ABSTRACT FROM AUTHOR]

The present research study compared two endodontic sealer cements, one zinc oxide and eugenol based (Roth 801) and the other one resin based (AH26) on their influence on the retention of glass fiber posts cemented with a dual resin cement (Variolink II). There was a statistically significant difference between the groups. The posts cemented on canals where the resin based sealer was used, needed stronger values of force to be dislodged compared to those where a ZOE based sealer was used. [ABSTRACT FROM AUTHOR]

The present work carries out a study of some physical-mechanical properties of materials composed of polymeric matrix, with different kind of filler of glass fiber and fillers from national sources, the last ones with the purpose of optimizing properties and to reduce costs. They were carried out the test of tensile strength, module of elasticity, shore hardness and Izod impact tests. All the experimental results were processed using the professional package STATGRAPHICS 4.1 in order to obtain the regression equations, as well as the graphic behavior of the properties. [ABSTRACT FROM AUTHOR]