Utilizing Recycled Polypropylene Fibers as Reinforcement for Concrete Beams

Polypropylene (PP) fibers are among numerous plastic waste materials, which are generated by the different industrial and domestic activities. Due to its low biodegradability, plastic waste constitutes a real environmental problem. The valorization of recycled PP fibers in the fabrication of concrete is one of the efficient solutions to cater for the environmental problems induced by plastic waste. In this experimental work, the workability and the mechanical properties of concrete are examined with different content ratios of recycled PP fibers. The mechanical behavior and the failure mode of concrete beams reinforced with recycled PP fibers are also studied. The used PP fibers are recycled from plastic waste of PLAST BROS factory in BordjBouArreridj, in Algeria. The fiber's diameter varies between 0.7 and 0.9mm. The various fiber content ratios tested in this investigation are 0.25, 0.5 and 1%. Based on the results of this study, the presence of recycled PP fibers in concrete decreases its workability; the addition of an adequate superplasticizer to the concrete mix becomes then necessary. Nevertheless, a positive effect is observed on its mechanical behavior. Indeed, in the presence of steel bars, reinforcing concrete beams with recycled PP fibers improves greatly their ductility and delays the appearance of cracks

Investment style of Jordanian mutual funds

The study investigates the mutual funds investment style in the Jordanian context. It uses monthly returns of five mutual funds from July 2000 to December 2009. To do so, it employs the 4-factors model with explanatory variables the market portfolio return, a small minus large capitalization indicator variable, a high minus low book-to-market indicator variable, and a variable that account for momentum effect. These factors are used as benchmarks to investigate the investment style. The results indicate that mutual funds returns tend to follow those of the market portfolio. In terms of investment style, mutual funds managers tend to favor small capitalization stocks, past winners stocks, and low book-to-market ratio stocks, respectively

Study of the Reinforcement of Limestone Mortars by Polypropylene Fibers Waste

AbstractThe first objective of this study is the valorisation of limestone waste produced from the crushing stations by using it as fine sand for mortars mixes and hence replaces the river sand. The second objective is the reinforcement of mortars by polypropylene fibers waste coming from the fabrication of domestic brushes and sweeps. In this paper we presented the results of physical and mechanical properties of reinforced mortars prepared with limestone sand which is in abundance in the city of Laghouat situated in 400km in the South of Algiers. The fibers dosages used are: 0.5, 1, 2 and 4wt% with length of 10, 20 and 30mm. The results of this investigation put in evidence the efficiency of the reinforcement of limestone mortars by polypropylene fibers waste in the improvement of their flexural tensile and compression strength. © 2010 Published by Elsevier B.V

The perceptions and experiences of Arabic mother tongue students in years 5 to 8 primary schooling in New Zealand when learning to read in English as a second language.

This study addressed the perceptions and experiences of Arabic-speaking ten to thirteen year-old students in New Zealand primary schools, and the teachers of these students in reading English as a second language (ESL). It aimed to better understand the supports and barriers that these students encountered when learning to read English. A qualitative approach was adopted to collect and analyse the data. Semi- structured interviews were conducted with eight primary school ESOL (English for Speakers of Other Languages) Arabic-speaking students and two ESOL teachers. Themes that describe the perceptions and experiences of ESOL students and ESOL teachers in reading ESL were generated from the data analysis. The findings indicated that the students and the teachers agreed on the supports for learning reading, but they conveyed different views regarding the barriers that students encounter when they read English. The students and the teachers agreed on the beneficial role of the students’ mother tongue in learning reading. The students confirmed how translating ambiguous words into their mother tongue enabled them to understand better the meaning of the word. They also conveyed their worries of losing their mother tongue. The teachers explained how a student’s mother tongue is the foundation for their learning. The barriers from the students’ views were difficulties in decoding, comprehending some words, and their embarrassment when required to read aloud in English to large groups of their peers. However, the teachers highlighted two main barriers that they perceived hampered Arabic-speaking students in learning to read in English, as their embarrassment about their accent which might be viewed as mispronunciation by their peers and the difficulty of finding reading texts that represented ESOL students’ culture

Recycled Polypropylene Fibres for Reinforcing Cement Mortar under Arid Conditions

Concreting in arid environment is a delicate operation, due to many problems, such as the premature evaporation of mixing water, which affects the material consistency and the shrinkage cracking which threatens its durability. The present experimental work is conducted to investigate the physical and the mechanical behaviour of cement mortar reinforced by recycled polypropylene fibres under arid conditions, at 45 °C and 30% RH. The used polypropylene fibres are recycled from a domestic plastic waste. The tests realized in this investigation include the workability, the total shrinkage, the flexure and the compression tests. Through this investigation, the beneficial effect of recycled polypropylene fibres as reinforcement of cement mortar is well demonstrated, particularly under arid environmental conditions. The obtained results showed a substantial increase in the flow time of about 53% in mortar reinforced by 1% of recycled polypropylene fibres (1RPFM). It is also shown that under arid conditions, the presence of 1% of recycled polypropylene fibres in cement mortar leads to a considerable decrease in total shrinkage of about 46% and an increase in the flexural and compressive strength of about 24% and 26%, respectively, compared to control mortar (CM) at the age of 194 days. Overall, the used recycled polypropylene fibres have presented a high capacity to improve the different properties of cement mortar and make it a suitable composite for concreting in arid environment

Omvårdnadshandlingar och faktorer som stödjar egenvård hos patienter med

Bakgrund: Diabetes är en sjukdom som har ökat globalt senaste åren. Ungefär 5-7% av den svenska befolkningen har diabetes, varav 90% är diagnosernas med diabetes typ 2 som drabbar främst vuxna. Diabetes typ 2 är en livsstilsrelaterad sjukdom där egenvård är en väsentlig del i behandlingen av diabetes typ 2. Syfte: Syftet med studien är att belysa sjuksköterskans omvårdnadshandlingar och faktorer som kan stödja patienter med diabetes typ 2 upplevelse av att genomföra sin egenvård. Metod: Examensarbetet bygger på en litteraturöversikt som består av tio vetenskapliga artiklar med kvalitativ metod som analyserades och kvalitetsgranskades enligt Friberg (2017a). Databaserna CINAHL och PubMed användes för att hitta relevanta artiklar. Resultat: I litteraturöversiktens resultat framkom det att patienter med diabetes typ 2 upplevde att acceptans och ansvarstagande i diabetessjukdomen är viktig för att genomföra egenvård. Relationer kan vara både stödjande och förhindrande. Sjuksköterskans bemötande och kompetens är nödvändigt för att patienter med diabetes typ 2 ska uppleva omvårdnadshandlingar positivt. Patientutbildningar är även en viktig förutsättning för att uppnå en god egenvård. Slutsats: Patientens acceptans, sjuksköterskans bemötande samt kompetens, sociala relationer och patientutbildningar ansågs som viktiga faktorer för att stödja en god egenvård

Assessment of the genotoxicity of quinolone and fluoroquinolones contaminated soil with the Vicia faba micronucleus test

The genotoxicity of quinolone and fluroquinolones was assessed using the micronucleus (MN) test on Viciafaba roots by direct contact exposure to a solid matrix. Plants were exposed to quinolones (nalidixic acid) and fluoroquinolones (ciprofloxacin and enrofloxacin) alone or mixed with artificially contaminatedsoils. Four different concentrations of each of these antibiotics were tested (0.01, 0.1, 1 and 10 mg/Kg) for nalidixic acid and (0.005, 0.05, 0.5 and 5 mg/Kg) for ciprofloxacin and enrofloxacin. These antibiotics were also used in mixture. Exposure of Vicia faba plants to each antibiotic at the highest two concentrations showed significant MN induction. The lowest two concentrations had no significant genotoxic effect. The mixture of the three compounds induced a significant MN induction whatever the mixture tested, from 0.02 to 20 mg/Kg. The results indicated that a similar genotoxic effect was obtained with the mixture at 0.2 mg/Kg in comparison with each molecule alone at 5–10 mg/Kg. Data revealed a clear synergism of these molecules on Vicia faba genotoxicity

The sensing characteristics of ZnO tetrapods synthesized by microwave evaporation

ZnO tetrapods have been grown by an environmental microwave evaporation approach in air atmosphere without any use of organic solvents or precursors. The synthesized powder was characterized using X-ray diffractometry (XRD) and Field emission Scanning Electron Microscopy (FE-SEM). The grown ZnO tetrapods exhibited a noteworthy microstructure and phase formation of crystalline and pure structure. ZnO tetrapods were deposited on Pt electrode to be employed as ZnO tetrapods structure-based sensors, then, they were investigated at room temperature in the relative humidity ranging from 0.0 to 96.0%. The sensors have shown a significant response towards relative humidity starting from 30%. Cross-sensitivity was investigated with respect to N2O (150 ppm in helium) and methane (1000 ppm in helium). The ZnO tetrapods-based sensors were insensitive towards the interfering gases, indicating a potential applicability for humidity sensing purposes

Synthesis and Characterization of Nano-Tungsten Oxide Precipitated onto Natural Inorganic Clay for Humidity-Sensing Applications

A wet chemical method was used to obtain tungsten oxide nanoparticles from tungsten tetrachloride and natural microfibrous inorganic clay (sepiolite) as a starting material. Precipitation of tungsten oxide species onto sepiolite under basic conditions and subsequent thermal treatment was investigated, prompted by the abundance of sepiolite in nature and the useful environmental applications that could be attained. Laser granulometry, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and high-resolution transmission electron microscopy (HR-TEM) techniques were used to study the particle-size distribution, the morphology, and the composition of the prepared sample. Our findings show the presence of tungsten oxide nanoparticles, which are less than 50 nm, on the needles of the modified sepiolite