scholarly journals Incorporation of Recycled Tire Products in Pavement-Grade Concrete: An Experimental Study

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 161
Author(s):  
Sayed Mohamad Soleimani ◽  
Abdel Rahman Alaqqad ◽  
Adel Jumaah ◽  
Naser Mohammad ◽  
Alanoud Faheiman
Keyword(s):  
Road Safety ◽  
Modulus Of Rupture ◽  
Long Term Effects ◽  
Split Tensile Strength ◽  
Element Analysis ◽  
Green Concrete ◽  
Hot Weather ◽  
By Products ◽  
Different Doses

The phenomenon of dumping used tires in Kuwait has reached critical levels, with a landfill containing millions of tires being formed in a remote area, which is a major environmental hazard. Nowadays, recycled rubber is used as a suitable and useful material in civil engineering applications, particularly in the production of “green concrete”. This study aims to see whether recycled tire by-products can be used to make “green concrete” for pavements. Each type of tire by-product was tested individually to examine its properties and effects on a benchmark mix before creating hybrid mixes that contain a combination of the materials. Eleven mixes containing different doses of shredded or crumbed rubber or steel fibers contained within the tires were made to evaluate their impact on the concrete’s slump, compressive strength, split tensile strength, and modulus of rupture. Additionally, twelve hybrid concrete mixes containing different doses of various tire by-products were developed. Preliminary results show that the incorporation of rubber products has a reduction on the concrete’s properties. The use of replacement materials sourced from recycled tires using the dosages investigated in this study does not detract from the usability of green pavement concrete suited for hot weather. The concrete produced in this study could be evaluated for specific properties relating to its road safety in further studies. Additionally, long-term effects of using the concrete can be studied using finite element analysis.

Lifelong Consumption of Plant-Based GM Foods

2019 ◽  
pp. 158-176 ◽  
Author(s):  
Matthew Chidozie Ogwu
Keyword(s):  
Antibiotic Resistance ◽  
Interdisciplinary Research ◽  
Long Term Effects ◽  
Resistance Development ◽  
Gm Foods ◽  
Alien Genes ◽  
Biotechnology Companies ◽  
By Products ◽  
Gm Plant

Genetically modified (GM) crops are cultivated in over 30 countries with their products and by-products imported by over 60 countries. This chapter seeks to highlight general concerns and potential lifelong effects of consuming GM plant-based food. The consumption of GM plant-based food is as risky as consuming conventional plant-based food. However, the alien genes in these products may be unstable leading to antinutritional and unintended short-term consequences. Due to the paucity of research, no long-term effects have been attributed to the lifelong consumption of these products. Nonetheless, possible lifelong health and socioeconomic effects may result from outcrossing of genes, increasing antibiotic resistance, development of new diseases, as well as potential effects on the environment and biodiversity. Biotechnology companies need to invest more in interdisciplinary research addressing the potential lifelong effects of these products. Although GM foods are safe for consumption, clarification of current risks and lifelong effects are required.

scholarly journals Mechanical Properties of Geopolymer Concrete with Flyash and Metakaolin

2019 ◽  
Vol 9 (1) ◽  
pp. 3863-3868 ◽  
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Sodium Hydroxide ◽  
Silica Content ◽  
Geopolymer Concrete ◽  
Long Term Effects ◽  
Concrete Production ◽  
High Silica ◽  
By Products

Trials has been made to produce efficient GPC which gives maximum strength. By-Products from industries such as Fly-Ash, Metakaolin and GGBS can be used in concrete replacement which in-turn reduces carbon-di-oxide (CO2 ) emission affecting to green house. Using the above said products also leads to reduction of water demand in concrete and also shows comparatively no effects on long term effects in concrete, these by-products can effectively be used in concrete production. The high silica content in Fly-Ash and Metakaolin increases the bonding in concrete which in-turn increases the mechanical properties of concrete. Geopolymer concrete of M50 grade was proposed to be produced using fly-ash and Metakaolin instead of cement.Alklai solutions Sodium Hydroxide (NaOH), Sodium Silicate (Na2SiO3) were replaced with water for better bonding and mixing. Molarity of Sodium Hydroxide with 10M and 12M was considered for this study. Ratio of Alkaline solution were considered as 1:2,1:2.5&1:3 to determine the optimum ratio which gives effective strength. In this experimental study, tests were carried on concrete specimens with percentage replacement of Fly-Ash with Buff Metakaolin in variable percentages of 20,40,60,80&100. Mechanical properties of concrete specimens were studied and were compared with control mix results.

Fatigue Prediction Verification of Fiberglass Hulls

2001 ◽  
Vol 38 (04) ◽  
pp. 278-292
Author(s):  
Paul H. Miller
Keyword(s):  
Finite Element ◽  
Fatigue Tests ◽  
Boiling Water ◽  
Tensile Failure ◽  
Analytical Models ◽  
Ship Motions ◽  
Long Term Effects ◽  
Element Analysis ◽  
Design Factor

The growing use of marine composite materials has led to many technical challenges and one is predicting lifetime durability. This analysis step has a large uncertainty due to the lack of data from in-service composite vessels. Analytical models based on classical lamination theory, finite-element analysis, ship motions, probability and wind and wave mechanicswere used in this project to predict hull laminate strains, and fatigue tests were used to determine S-N residual stiffness properties of coupons. These predictions and test data were compared against two cored fiberglass sisterships having significantly different fatigue histories and undamaged laminates representing a new vessel. Strains were measured while underway and good correlation was achieved between predictions and measurements. Fatigue damage indicators were identified which could be used in vessel inspection procedures. Endurance limits were found to be near 25% of static failure load, indicating that a fatigue design factor of four is required for infinite service with this material. Standard moisture experiments using boiling water were compared with long-term exposure. Results indicated the boiling water test yielded significantly conservative values and was not a reliable means of predicting long-term effects. Panel tests were compared with a combined coupon and finite-element procedure. Results indicated the proposed procedure was a viable substitute, at least for the materials studied. A rational explanation for using thicker outer skin laminates in marine composites was identified through single-sided moisture flex tests. These showed that the reduced strength and stiffness due to moisture of the outer hull skin laminate could be compensated by increased thickness. Although the resulting unbalanced laminate is not ideal from a warping standpoint, the approach leads to consistent tensile failure of the inner skin when subjected to normal loads. Permeability considerations make this desirable for hull laminates.

RESEARCH ON THE LONG-TERM EFFECTS OF THE CARBOHYDRATE-VITAMIN-MINERAL CONCENTRATE “LIZUNETS SOLEVIT”

2020 ◽  
Vol 15 (8) ◽  
pp. 1147-1153
Author(s):  
D.D. Khayrullin ◽  
Keyword(s):  
Aqueous Suspension ◽  
Animal Husbandry ◽  
The Body ◽  
Control Group ◽  
Long Term Effects ◽  
Rat Pups ◽  
White Rats ◽  
Production Increase ◽  
Different Doses

The main factors constraining the development of animal husbandry is a weak fodder base, due to insufficient supply of nutrients; the costs of its production increase and becomes the cause of metabolic disorders in animals. The aim of our research was to study the embryotoxic and teratogenic effect of the new CVMC “Lizunets-Solevit” on white rats. For this reason, the drug was administered to pregnant females in the form of an aqueous suspension in different doses for 19 days. By the end of the study, no visible signs of fetal abnormalities were found after autopsy of the experimental rats. There was no significant increase in the number of corpus luteum compared with the control group at 1/10 dose by 1.1% and 1/20 dose by 1.95%, respectively. The preimplantation death of zygotes was taken into account on the embryotoxic effect of the drug, in comparison with the control group at a dose of 1/10 more by 19.7%, and at a dose of 1/20 less by 6.23%. The total embryonic mortality is higher in the experimental groups of animals by 12.69% and 3.74% than in the control. Post-implantation death of embryos in the control group was 4.99%, in the experimental 1/10 dose - 4.69% and in the experimental 1/20 dose - 6.66%. In terms of physiological development, the rat pups of the experimental groups did not differ from the control. Thus, it was found that CVMC “Lizunets-Solevit”, in doses of 1/10 and 1/20, has no embryotoxic and teratogenic effects in the body of white rats, their embryos and young animals of the neonatal and postnatal periods of life.

scholarly journals Promoção da mobilidade sustentável através de atividades lúdicas com bicicletas na educação infantil

2020 ◽  
Vol 42 ◽  
pp. 2
Author(s):  
Juliana Aguiar Macedo ◽  
Brenda Medeiros Pereira ◽  
Alejandro Ruiz- Padillo
Keyword(s):  
Urban Space ◽  
Road Safety ◽  
Academic Community ◽  
Long Term Effects ◽  
The Public ◽  
Supporting Material ◽  
The City ◽  
Santa Maria

Children connect with the city mainly through their trips to school. Since childhood children can develop the interest in taking care of the public spaces that surrounds them and develop a questioning character. The Pedala Kids extension project seeks to encourage children to ride bikes and interact with urban space through activities aimed at increasing road safety, encouraging active mobility and respect for life, with long-term effects, contributing to a well-functioning of the city. In partnership with a school in Cachoeira do Sul, the Federal University of Santa Maria - Campus Cachoeira do Sul held the Cycling Games. The aim of this paper is to present the experience of the Games as a playful activity that seeks to contribute to citizenship enhancement of children. With four main stages, the Games had four main steps: brief literature review, meetings with partner agencies for project structuring, preparation of supporting material and realization of the Cycling Games’ activities. Thus, this project stimulates the engagement of the academic community in promoting the quality of life of the population of Cachoeira do Sul.

Lifelong Consumption of Plant-Based GM Foods

2021 ◽  
pp. 1168-1186
Author(s):  
Matthew Chidozie Ogwu
Keyword(s):  
Antibiotic Resistance ◽  
Interdisciplinary Research ◽  
Long Term Effects ◽  
Resistance Development ◽  
Gm Foods ◽  
Alien Genes ◽  
Biotechnology Companies ◽  
By Products ◽  
Gm Plant

Genetically modified (GM) crops are cultivated in over 30 countries with their products and by-products imported by over 60 countries. This chapter seeks to highlight general concerns and potential lifelong effects of consuming GM plant-based food. The consumption of GM plant-based food is as risky as consuming conventional plant-based food. However, the alien genes in these products may be unstable leading to antinutritional and unintended short-term consequences. Due to the paucity of research, no long-term effects have been attributed to the lifelong consumption of these products. Nonetheless, possible lifelong health and socioeconomic effects may result from outcrossing of genes, increasing antibiotic resistance, development of new diseases, as well as potential effects on the environment and biodiversity. Biotechnology companies need to invest more in interdisciplinary research addressing the potential lifelong effects of these products. Although GM foods are safe for consumption, clarification of current risks and lifelong effects are required.

Ovarian Dysfunction in Fetally Irradiated Beagles

1977 ◽  
Vol 35 ◽  
pp. 658-659
Author(s):  
T. M. Seed ◽  
M. H. Sanderson ◽  
D. L. Gutzeit ◽  
T. E. Fritz ◽  
D. V. Tolle ◽  
...  
Keyword(s):  
Gamma Rays ◽  
Low Dose ◽  
Long Term Effects ◽  
Ovarian Dysfunction ◽  
Dose Rates ◽  
Highly Sensitive ◽  
Microscopic Evaluation ◽  
Ovarian Pathology ◽  
Normal Offspring

The developing mammalian fetus is thought to be highly sensitive to ionizing radiation. However, dose, dose-rate relationships are not well established, especially the long term effects of protracted, low-dose exposure. A previous report (1) has indicated that bred beagle bitches exposed to daily doses of 5 to 35 R 60Co gamma rays throughout gestation can produce viable, seemingly normal offspring. Puppies irradiated in utero are distinguishable from controls only by their smaller size, dental abnormalities, and, in adulthood, by their inability to bear young.We report here our preliminary microscopic evaluation of ovarian pathology in young pups continuously irradiated throughout gestation at daily (22 h/day) dose rates of either 0.4, 1.0, 2.5, or 5.0 R/day of gamma rays from an attenuated 60Co source. Pups from non-irradiated bitches served as controls. Experimental animals were evaluated clinically and hematologically (control + 5.0 R/day pups) at regular intervals.

Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

1990 ◽  
Vol 48 (3) ◽  
pp. 374-375
Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson
Keyword(s):  
Antidepressant Drug ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Short Term ◽  
Platelet Counts ◽  
Toxicological Studies ◽  
Induced Aggregation ◽  
Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

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