Estudo Comparativo Entre o Concreto Leve de PET e o Concreto Leve de EPS

2018 ◽  
Vol 13 (13) ◽  
pp. 23
Author(s):  
Dieison De Souza Lima ◽  
Emily Do Amaral ◽  
Kauana Gabriela Rocha De Lima ◽  
Rafael Capellari Fumegali ◽  
Thiago Dias Do Espírito Santo
Keyword(s):  
Water Absorption ◽  
Solid Waste ◽  
Lightweight Concrete ◽  
Phase 1 ◽  
Expanded Polystyrene ◽  
Raw Material ◽  
Phase 2 ◽  
Adverse Conditions ◽  
The Third ◽  
Plastic Containers

A geração de grandes volumes de resíduos sólidos tem sido um dos maiores problemas ambientais encontrados na atualidade e certamente o mais preocupante. Com o descarte inadequado de certos materiais, muita matéria-prima deixa de ser reaproveitada, como as embalagens plásticas pós-consumo de Politereftalato de Etileno – PET, um produto capaz de sobreviver mais de cem anos em condições adversas no meio ambiente. Deste modo, com o intuito de reciclar as embalagens de PET e ao mesmo tempo empregá-las na construção civil, foram realizados ensaios de concreto utilizando o PET como matéria-prima na fabricação de concreto leve, comparando suas características com traços de concretos leves tradicionais confeccionados com Poliestireno Expandido – EPS, conhecido como isopor. Foram fabricados na Fase 1, corpos de prova dos traços de concreto com EPS para avaliar os parâmetros iniciais, os métodos de dosagem e a definição do traço referência. Com o traço referência definido foi fabricado um concreto leve apenas com PET buscando obter características similares ao do traço com EPS. Na Fase 2, foram fabricados a partir do traço referência quatro tipos de concreto leve, o primeiro com PET, o segundo de PET com aditivo Bianco, buscando melhor aderência entre a argamassa e o PET, o terceiro com EPS e o quarto de EPS com aditivo Bianco. As amostras foram caracterizadas pelos ensaios de compressão, densidade e absorção de água. Com os resultados pode-se perceber que os comportamentos dos traços de concreto leves se assemelham visualmente, diferenciando apenas em seus pesos e resistências à compressão. Palavras-chave: Concreto Leve. EPS. Isopor. PET. AbstractThe generation of large volumes of solid waste has been one of the biggest environmental problems found nowadays and certainly the most worrisome. With the inadequate disposal of certain materials, much of the raw material is no longer reused, such as the post-consumer plastic containers of Polyethylene Terephthalate (PET), a product capable of surviving more than 100 years in adverse conditions in the environment. Therefore, in order to recycle PET containers and at the same time to use them in construction, concrete tests were carried out using PET as a raw material in the manufacture of lightweight concrete, comparing its characteristics with traditional lightweight concrete formula made with Expanded Polystyrene - EPS, known as Styrofoam. Phase 1 concrete test specimens with EPS were produced to evaluate the initial parameters, the dosing methods and the reference concrete formula. With the reference concrete formula defined, a lightweight concrete was fabricated with PET only to obtain similar characteristics to the concrete formula with EPS. In Phase 2, four types of lightweight concrete were manufactured from the reference concrete formula, the first with PET, the second from PET with Bianco additive, seeking better adhesion between the mortar and the PET, the third with EPS and the fourth EPS with additive Bianco. The samples were characterized by compression, density and water absorption tests. With the results it can be seen that the behavior of the lightweight concrete formula resembles visually, differentiating only in their weights and resistance to compression. Keywords: Lightweight Concrete. EPS. Styrofoam. PET.

PENERAPAN MODEL QUANTUM LEARNING UNTUK MENINGKATKAN HASIL BELAJAR AUTOCAD SISWA KELAS X TEKNIK PEMESINAN SMK NEGERI 1 STABAT

2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Abdul Hasan Saragih
Keyword(s):  
Positive Response ◽  
Phase 1 ◽  
First Grade ◽  
Learning Model ◽  
Second Phase ◽  
Phase 2 ◽  
Phase 3 ◽  
The Third ◽  
Third Phase ◽  
Quantum Learning

This classroom research was conducted on the autocad instructions to the first grade of mechinary class of SMK Negeri 1 Stabat aiming at : (1) improving the student’ archievementon autocad instructional to the student of mechinary architecture class of SMK Negeri 1 Stabat, (2) applying Quantum Learning Model to the students of mechinary class of SMK Negeri 1 Stabat, arising the positive response to autocad subject by applying Quantum Learning Model of the students of mechinary class of SMK Negeri 1 Stabat. The result shows that (1) by applying quantum learning model, the students’ achievement improves significantly. The improvement ofthe achievement of the 34 students is very satisfactory; on the first phase, 27 students passed (70.59%), 10 students failed (29.41%). On the second phase 27 students (79.41%) passed and 7 students (20.59%) failed. On the third phase 30 students (88.24%) passed and 4 students (11.76%) failed. The application of quantum learning model in SMK Negeri 1 Stabat proved satisfying. This was visible from the activeness of the students from phase 1 to 3. The activeness average of the students was 74.31% on phase 1,81.35% on phase 2, and 83.63% on phase 3. (3) The application of the quantum learning model on teaching autocad was very positively welcome by the students of mechinary class of SMK Negeri 1 Stabat. On phase 1 the improvement was 81.53% . It improved to 86.15% on phase 3. Therefore, The improvement ofstudent’ response can be categorized good.

Efficient Eco-friendly Composite Fluorine Anhydrite-Based Materials

2017 ◽  
Author(s):  
Grigory Yakovlev ◽  
Jadvyga Keriene ◽  
Anastasiia Gordina ◽  
Irina Polyanskikh ◽  
Milan Bekmansurov
Keyword(s):  
Water Absorption ◽  
Lightweight Concrete ◽  
Gas Permeability ◽  
Average Density ◽  
Expanded Polystyrene ◽  
Environmental Load ◽  
Great Demand ◽  
Technogenic Waste ◽  
And Performance ◽  
Reduced Water

The paper presents possible ways of utilizing technogenic waste – fluorine anhydrite – by its use in production of dry mortars and piece goods from lightweight concrete with expanded polystyrene, as a organic filler, for low-rise construc-tion. The developed dry mortars are based on fluorine anhydrite binder and complex modifier comprising curing activator (sulfate or alkaline) and finely dispersed additive. The fluorine anhydrite-based compositions have improved physical and performance characteristics, including the improved strength and average density and reduced water absorption compared to the control composition. The developed lightweight anhydrite polystyrene concrete has the density grade of 700 kg/m3 and good vapor and gas permeability. The concrete is stabile while using and fire safe, because each granule of expanded poly-styrene is coated with anhydrite matrix, and has the strength sufficient for structural and heat insulating slabs and blocks. All mentioned compositions are eco-friendly and are in great demand for low-rise construction. Therefore the manufacturing of these compositions will consume a large amount of technogenic waste and will reduce the environmental load on the region where the waste is located.

Gene structure dynamics and divergence of the polygalacturonase gene family of plants and fungus

Genome ◽  
2008 ◽  
Vol 51 (1) ◽  
pp. 30-40 ◽  
Author(s):  
K.-C. Park ◽  
S.-J. Kwon ◽  
P.-H. Kim ◽  
T. Bureau ◽  
N.-S. Kim
Keyword(s):  
Gene Structure ◽  
Tandem Duplication ◽  
Phase Distribution ◽  
Gene Diversity ◽  
Phase 1 ◽  
Phase 2 ◽  
Intron Phase ◽  
The Third ◽  
Phase 0 ◽  
Per Gene

Whole copies of the polygalacturonase (PG) genes from rice ( Oryza sativa subsp. japonica) and a filamentous fungus ( Aspergillus oryzae ) were isolated. The orthologs of the rice PGs were also retrieved from other plant species. The 106 plant PGs analyzed were divided into 5 clades, A, B, C, D, and E. The fungus PGs were classified into 3 clades, of which one formed a loose cluster with clade E of the plant PGs. Four domain motifs (I, II, III, IV) were identified in all PGs. Motifs II and III were split by introns such as G/DDC and CGPGHGIS/IGSLG, respectively. In plant PGs there were 446 introns in total and 3.98 introns per gene. Intron phase distribution was 65.5% for phase 0, 19.7% for phase 1, and 14.8% for phase 2 in plant PGs. In the PGs of A. oryzae there were 37 introns of phase 0 (59.5%), phase 1 (24.3%), and phase 2 (16.2%), with 2.47 introns per gene. The 5 clades of plant PGs were divided into 3 basic gene structure lineages. Intron positions and phases were conserved among the PGs in the first 2 lineages. The third lineage consisted of PGs of clade E, which also carried highly conserved introns at different positions from other PGs. Intron positions were not as highly conserved in fungus PGs as in plant PGs. The introns in the current PGs have been present since before the divergence of monocots from dicots. The results obtained show that differential losses of introns created gene diversity, which was followed by segmental and tandem duplication in plant PGs.

scholarly journals Safety, tolerability, and immunogenicity of a SARS-CoV-2 recombinant spike protein vaccine: a randomised, double-blind, placebo-controlled, phase 1-2 clinical trial (ABDALA Study).

2021 ◽  
Author(s):  
Francisco Hernandez-Bernal ◽  
Maria del Carmen Ricardo-Cobas ◽  
Yenima Martin-Bauta ◽  
Zadis Navarro-Rodriguez ◽  
Marjoris Pinera-Martinez ◽  
...  
Keyword(s):  
Placebo Group ◽  
Neutralizing Antibodies ◽  
Phase 1 ◽  
Vaccination Schedule ◽  
Phase 2 ◽  
Igg Antibodies ◽  
Protein Vaccine ◽  
Double Blind ◽  
Double Blind Placebo ◽  
The Third

Aim: To evaluate the safety and immunogenicity of a SARS-CoV-2 recombinant spike protein vaccine (Abdala), administered intramuscularly in different strengths and vaccination schedules. Method: A phase 1-2, randomized, double-blind, placebo-controlled trial was done. Subjects were randomly distributed in 3 groups: placebo, 25 and 50 μg RBD. The product was applied intramuscularly, 0.5 mL in the deltoid region. During the first phase, two immunization schedules were studied: short (0-14-28 days) and long (0-28-56 days). In phase 2, only the short scheme was evaluated. The main endpoints were: safety and proportion of subjects with seroconversion of anti-RBD IgG antibodies to SARS-CoV-2. Blood samples were collected in several points according to the corresponding vaccination schedule to determine the level of RBD-specific IgG antibodies (seroconversion rates and geometric mean of the titers), the percentage of inhibition of RBD-ACE-2 binding and levels of neutralizing antibodies. Results: The product was well tolerated. Severe adverse events were not reported. Adverse reactions were minimal, mostly mild and local (from the injection site), resolved in the first 24-48 hours without medication. In phase 1, at day 56 (28 days after the third dose of the short vaccination schedule, 0-14-28 days) seroconversion of anti-RBD IgG was seen in 95.2 % of the participants (20/21) for the 50 μg group and 81 % of the participants (17/21) for the 25 μg group, and none in the placebo group (0/22); whereas neutralizing antibodies to SARS-CoV-2 were seen in 80 % of the participants (8/10) for the 50 μg group and 94.7% of the participants (18/19) for the 25 μg group. For the long schedule, at day 70 (14 days after the third dose) seroconversion of anti-RBD IgG was seen in 100% of the participants (21/21) for the 50 μg group and 94.7% of the participants (18/19) for the 25 μg group, and none in the placebo group (0/22); whereas neutralizing antibodies to SARS-CoV-2 were seen in 95 % of the participants (19/20) for the 50 μg group and 93.8% of the participants (15/16) for the 25 μg group In phase 2, at day 56 seroconversion of anti-RBD IgG was seen in 89.2% of the participants (214/240) for the 50 μg group, 77.7% of the participants (185/238) for the 25 μg group, and 4.6% in the placebo group (11/239); whereas neutralizing antibodies to SARS-CoV-2 were seen in 97.3% of the participants (146/150) for the 50 μg group and 95.1% of the participants (58/61) for the 25 μg group. Conclusion: Abdala vaccine against SARS-CoV-2 was safe, well tolerated and induced humoral immune responses against SARS-CoV-2 among adults from 19 to 80 years of age.

scholarly journals Absorption Characteristics of Lightweight Concrete Containing Densified Polystyrene

2017 ◽  
Vol 3 (8) ◽  
pp. 594-609 ◽  
Author(s):  
Bengin Herki
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Construction Industry ◽  
Lightweight Concrete ◽  
Expanded Polystyrene ◽  
Partial Replacement ◽  
The Novel ◽  
Total Water ◽  
Capillary Water ◽  
Significant Difference

The environmental impacts of the construction industry can be minimised through using waste and recycled materials to replace natural resources. Results are presented of an experimental study concerning capillary transport of water in concrete incorporating densified expanded polystyrene (EPS) as a novel aggregate. A new environmentally friendly technique of densifying was used to improve the resistance to segregation of EPS beads in concrete. Twelve concrete mixes with three different water/cement ratios of 0.6, 0.8 and 1.0 with varying novel aggregate content ratios of 0, 30, 60 and 100% as partial replacement for natural aggregate by equivalent volume were prepared and tested. Total absorption, absorption by capillary action, and compressive strength was determined for the various concrete mixes at different curing times. The results indicated that there is an increase in total water absorption (WA) and capillary water absorption (CWA) and a decrease in compressive strength with increasing amounts of the novel aggregate in concrete. However, there is no significant difference between the CWA of control and concretes containing lower replacement level.

scholarly journals Recovery and Incorporation of expanded polystyrene SolidWaste in Lightweight Concrete

Ingeniería ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 237-249
Author(s):  
María Paula Espinoza-Merchán ◽  
Laura Juliana Torres-Parra ◽  
Nicolas Rojas-Arias ◽  
Pablo Miguel Coha-Vesga
Keyword(s):  
Coarse Aggregate ◽  
Lightweight Concrete ◽  
Expanded Polystyrene ◽  
Raw Material ◽  
Low Density ◽  
Chemical Attack ◽  
High Consumption ◽  
Chemical Agents ◽  
Concrete Failure ◽  
Attack Process

Context: The high consumption of parts made from expanded polystyrene (EPS) generates environmental problems when disposed. Due to its low density and the low possibility of being utilized in other applications after its disposal, it is necessary to generate an alternative for the recovery and application of this type of waste. This work aims to generate an alternative in the application of EPS waste, particularly as a coarse aggregate in the manufacturing of lightweight concrete. Method: This study used discarded EPS containers as raw material. The material was cleaned, crushed and subsequently reduced in volume by applying acetone, generating pieces of polystyrene (R-PS) to be applied as a coarse aggregate for the manufacturing of lightweight concrete in different proportions. In addition, the pieces were subjected to a chemical attack process in order to observe their behavior. Results: The results show the degree of volume reduction of the EPS pieces by using different acetone ratios, establishing the best degree of reduction (in volume) of this material. Likewise, chemical attack tests show the behavior of R-PS against different agents in R-PS samples. Meanwhile, the failure tests on different concrete samples determine the best R-PS ratio as coarse aggregate for the manufacturing of lightweight concrete. Conclusions: The data obtained in this study show that the application of acetone on EPSW samples reduces its volume by up to 55 %. Concrete failure tests show that an optimum P-RS addition value, to be used as an aggregate in the manufacturing of lightweight concrete, is 7 %. This improves its resistance to chemical agents and weight reduction without significantly reducing the mechanical properties of concrete.

scholarly journals How Do Astronaut Candidate Profiles Differ From Airline Pilot Profiles?

2011 ◽  
Vol 1 (1) ◽  
pp. 38-44 ◽  
Author(s):  
Peter Maschke ◽  
Viktor Oubaid ◽  
Yvonne Pecena
Keyword(s):  
Phase 1 ◽  
European Space Agency ◽  
Interpersonal Behavior ◽  
Performance Tests ◽  
Phase 2 ◽  
The Third ◽  
Airline Pilot ◽  
Space Agency ◽  
Scientific Experiments ◽  
High Level

Sixteen years after the second Europe-wide astronaut selection campaign, the European Space Agency started the third campaign by putting out a call for new astronauts in 2008. Due to extreme environmental conditions, expensive scientific experiments, and high public interest, not only are the psychological requirements on a high level, but they are also wide in variety: Besides cognitive and psychomotor requirements, greater importance than in comparable campaigns was put on personality and behavioral aspects, especially regarding interpersonal aspects. The psychological selection was conducted in two steps: Phase 1 concentrated mainly on performance tests and Phase 2 focused on personality and interpersonal behavior. Out of the 902 tested candidates, 46 fulfilled the psychological requirements. Significant differences were found between the astronaut candidates and the general population as well as airline pilot candidates.

Lightweight Concrete Incorporating Waste Expanded Polystyrene

2013 ◽  
Vol 787 ◽  
pp. 131-137 ◽  
Author(s):  
B.A. Herki ◽  
Jamal M. Khatib
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Lightweight Concrete ◽  
Lightweight Aggregate ◽  
Ultrasonic Pulse Velocity ◽  
Pulse Velocity ◽  
Expanded Polystyrene ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Waste Polystyrene

This paper covers the results of an experimental investigation on mechanical and durability properties of concrete containing waste polystyrene based lightweight aggregate called Stabilised Polystyrene (SPS) as a partial replacement of natural aggregates. The properties investigated in this paper were water absorption by capillary action and total absorption, compressive strength and ultrasonic pulse velocity (UPV). The composite aggregate was formed with 80% waste polystyrene which was shredded to different sizes, 10% of a natural additive to improve the resistance to segregation and 10% Portland cement. The natural fine aggregate were replaced with 0%, 30%, 60% and 100% (by volume) of SPS. There was an increasing in water absorption and a decreasing in compressive strength and UPV with the increase in SPS aggregate content in concrete.

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