Search results for: aggregate fractions

Authors: Fernando M. Soto, Gaetano Di Mino

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The design of an unmodified bituminous mixture and three rubber-aggregate mixtures containing rubber-aggregate by a dry process (RUMAC) was evaluated, using an empirical-analytical approach based on experimental findings obtained in the laboratory with the volumetric mix design by gyratory compaction. A reference dense-graded bituminous sub-ballast mixture (3% of air voids and a bitumen 4% over the total weight of the mix), and three rubberized mixtures by dry process (1,5 to 3% of rubber by total weight and 5-7% of binder) were used applying the Superpave mix-design for a level 3 (high-traffic) design rail lines. The railway trackbed section analyzed was a granular layer of 19 cm compacted, while for the sub-ballast a thickness of 12 cm has been used. In order to evaluate the effect of increasing the specimen density (as a percent of its theoretical maximum specific gravity), in this article, are illustrated the results obtained after different comparative analysis into the influence of varying the binder-rubber percentages under the sub-ballast layer mix-design. This work demonstrates that rubberized blends containing crumb and ground rubber in bituminous asphalt mixtures behave at least similar or better than conventional asphalt materials. By using the same methodology of volumetric compaction, the densification curves resulting from each mixture have been studied. The purpose is to obtain an optimum empirical parameter multiplier of the number of gyrations necessary to reach the same compaction energy as in conventional mixtures. It has provided some experimental parameters adopting an empirical-analytical method, evaluating the results obtained from the gyratory-compaction of bituminous mixtures with an HMA and rubber-aggregate blends. An extensive integrated research has been carried out to assess the suitability of rubber-modified hot mix asphalt mixtures as a sub-ballast layer in railway underlayment trackbed. Design optimization of the mixture was conducted for each mixture and the volumetric properties analyzed. Also, an improved and complete manufacturing process, compaction and curing of these blends are provided. By adopting this increase-parameters of compaction, called 'beta' factor, mixtures modified with rubber with uniform densification and workability are obtained that in the conventional mixtures. It is found that considering the usual bearing capacity requirements in rail track, the optimal rubber content is 2% (by weight) or 3.95% (by volumetric substitution) and a binder content of 6%.

Keywords: empirical approach, rubber-asphalt, sub-ballast, superpave mix-design

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Authors: Qi Wu, Dian-Yong Chen, Feng-Kun Guo, Gang Li

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In the past decade, a growing number of new hadron states have been observed, which are dubbed as XYZ states in the heavy quarkonium mass regions. In this work, we present our study on the production of some new hadron states. In particular, we investigate the processes Υ(5S,6S)→ Zb (10610)/Zb (10650)π, Bc→ Zc (3900)/Zc (4020)π and Λb→ Pc (4312)/Pc (4440)/Pc (4457)K. (1) For the production of Zb (10610)/Zb (10650) from Υ(5S,6S) decay, two types of bottom-meson loops were discussed within a nonrelativistic effective field theory. We found that the loop contributions with all intermediate states being the S-wave ground state bottom mesons are negligible, while the loops with one bottom meson being the broad B₀* or B₁' resonance could provide the dominant contributions to the Υ(5S)→ Zb⁽'⁾ π. (2) For the production of Zc (3900)/Zc (4020) from Bc decay, the branching ratios of Bc⁺→ Z (3900)⁺ π⁰ and Bc⁺→ Zc (4020)⁺ π⁰ are estimated to be of order of 10⁽⁻⁴⁾ and 10⁽⁻⁷⁾ in an effective Lagrangian approach. The large production rate of Zc (3900) could provide an important source of the production of Zc (3900) from the semi-exclusive decay of b-flavored hadrons reported by D0 Collaboration, which can be tested by the exclusive measurements in LHCb. (3) For the production of Pc (4312), Pc (4440) and Pc (4457) from Λb decay, the ratio of the branching fraction of Λb→ Pc K was predicted in a molecular scenario by using an effective Lagrangian approach, which is weakly dependent on our model parameter. We also find the ratios of the productions of the branching fractions of Λb→ Pc K and Pc→ J/ψ p can be well interpreted in the molecular scenario. Moreover, the estimated branching fractions of Λb→ Pc K are of order 10⁽⁻⁶⁾, which could be tested by further measurements in LHCb Collaboration.

Keywords: effective Lagrangian approach, hadron loops, molecular states, new hadron states

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Authors: Ichiro Takahashi

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One conundrum that macroeconomic theory faces is to explain how an economy can revive from depression, in which the aggregate demand has fallen substantially below its productive capacity. This paper examines an autonomous stabilizing mechanism using an agent-based Wicksell-Keynes macroeconomic model. This paper focuses on the effects of the number of firms and the length of the gestation period for investment that are often assumed to be one in a mainstream macroeconomic model. The simulations found the virtual economy was highly unstable, or more precisely, collapsing when these parameters are fixed at one. This finding may even suggest us to question the legitimacy of these common assumptions. A perpetual decline in capital stock will eventually encourage investment if the capital stock is short-lived because an inactive investment will result in insufficient productive capacity. However, for an economy characterized by a roundabout production method, a gradual decline in productive capacity may not be able to fall below the aggregate demand that is also shrinking. Naturally, one would then ask if our economy cannot rely on an external stimulus such as population growth and technological progress to revive investment, what factors would provide such a buoyancy for stimulating investments? The current paper attempts to answer this question by employing the artificial macroeconomic model mentioned above. The baseline model has the following three features: (1) the multi-period gestation for investment, (2) a large number of heterogeneous firms, (3) demand-constrained firms. The instability is a consequence of the following dynamic interactions. (a) A multiple-period gestation period means that once a firm starts a new investment, it continues to invest over some subsequent periods. During these gestation periods, the excess demand created by the investing firm will spill over to ignite new investment of other firms that are supplying investment goods: the presence of multi-period gestation for investment provides a field for investment interactions. Conversely, the excess demand for investment goods tends to fade away before it develops into a full-fledged boom if the gestation period of investment is short. (b) A strong demand in the goods market tends to raise the price level, thereby lowering real wages. This reduction of real wages creates two opposing effects on the aggregate demand through the following two channels: (1) a reduction in the real labor income, and (2) an increase in the labor demand due to the principle of equality between the marginal labor productivity and real wage (referred as the Walrasian labor demand). If there is only a single firm, a lower real wage will increase its Walrasian labor demand, thereby an actual labor demand tends to be determined by the derived labor demand. Thus, the second positive effect would not work effectively. In contrast, for an economy with a large number of firms, Walrasian firms will increase employment. This interaction among heterogeneous firms is a key for stability. A single firm cannot expect the benefit of such an increased aggregate demand from other firms.

Keywords: agent-based macroeconomic model, business cycle, demand constraint, gestation period, representative agent model, stability

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Authors: S. R. Shamili, C. Natarajan, J. Karthikeyan

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Rapid growth of world population and widespread urbanization has remarkably increased the development of the construction industry which caused a huge demand for sand and gravels. Environmental problems occur when the rate of extraction of sand, gravels, and other materials exceeds the rate of generation of natural resources; therefore, an alternative source is essential to replace the materials used in concrete. Now-a-days, electronic products have become an integral part of daily life which provides more comfort, security, and ease of exchange of information. These electronic waste (E-Waste) materials have serious human health concerns and require extreme care in its disposal to avoid any adverse impacts. Disposal or dumping of these E-Wastes also causes major issues because it is highly complex to handle and often contains highly toxic chemicals such as lead, cadmium, mercury, beryllium, brominates flame retardants (BFRs), polyvinyl chloride (PVC), and phosphorus compounds. Hence, E-Waste can be incorporated in concrete to make a sustainable environment. This paper deals with the composition, preparation, properties, classification of E-Waste. All these processes avoid dumping to landfills whilst conserving natural aggregate resources, and providing a better environmental option. This paper also provides a detailed literature review on the behaviour of concrete with incorporation of E-Wastes. Many research shows the strong possibility of using E-Waste as a substitute of aggregates eventually it reduces the use of natural aggregates in concrete.

Keywords: dumping, electronic waste, landfill, toxic chemicals

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Authors: M. Murmu, Govardhan, J. Satya Eswari

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Concrete is the most common and widely used building material. Concrete is basically made of aggregates, both fine and coarse, glued by a cement paste which is made of cement and water. Each one of these constituents of concrete has a negative environmental impact and gives rise to different sustainability issues. The current concrete construction practice is unsustainable because, not only it consumes enormous quantities of stones, sand, and drinking water, but also one billion tons a year of cement, which is not an environment friendly material. Preventing the reduction of natural resources and enhancing the usage of waste materials has become a challenge to the scientist and engineers. A number of studies have been conducted concerning the protection of natural resources, prevention of environmental pollution and contribution to the economy by using this waste material. This paper outlines the influence of Ground Granulated Blast furnace Slag (GGBS) as partial replacement of fine aggregate on mechanical properties of concrete. The strength of concrete is determined having OPC binder, replaced the fine aggregate with15%, 30%, 45% respectively. For this purpose, characteristics concrete mix of M25 with partial replacement of cement with GGBS is used and the strength of concrete cubes and cylinder have determined. The strength of concrete specimens has been compared with the reference specimen. Also X-ray diffraction (XRD) and scanning electron microscope (SEM) tests have been performed to examine the hydration products and the microstructure of the tested specimens. A correlation has been established between the developmental strength concrete with and without GGBS through analysis of hydration products and the microstructure.

Keywords: GGBS, sand, concrete, workability

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Authors: Jitka Hroudová, Martin Sedlmajer, Jiří Zach

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Problems insulation of building structures is often closely connected with the problem of moisture remediation. In the case of historic buildings or if only part of the redevelopment of envelope of structures, it is not possible to apply the classical external thermal insulation composite systems. This application is mostly effective thermal insulation plasters with high porosity and controlled capillary properties which assures improvement of thermal properties construction, its diffusion openness towards the external environment and suitable treatment capillary properties of preventing the penetration of liquid moisture and salts thereof toward the outer surface of the structure. With respect to the current trend of reducing the energy consumption of building structures and reduce the production of CO2 is necessary to develop capillary-active materials characterized by their low density, low thermal conductivity while maintaining good mechanical properties. The aim of researchers at the Faculty of Civil Engineering, Brno University of Technology is the development and study of hygrothermal behaviour of optimal materials for thermal insulation and rehabilitation of building structures with the possible use of alternative, less energy demanding binders in comparison with conventional, frequently used binder, which represents cement. The paper describes the evaluation of research activities aimed at the development of thermal insulation and repair materials using lightweight aggregate and alternative binders such as metakaolin and finely ground fly ash.

Keywords: thermal insulating plasters, rehabilitation materials, thermal conductivity, lightweight aggregate, alternative binders.

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Authors: Salem Alsanusi, Loubna Bentaher

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Response Surface Methods (RSM) provide statistically validated predictive models that can then be manipulated for finding optimal process configurations. Variation transmitted to responses from poorly controlled process factors can be accounted for by the mathematical technique of propagation of error (POE), which facilitates ‘finding the flats’ on the surfaces generated by RSM. The dual response approach to RSM captures the standard deviation of the output as well as the average. It accounts for unknown sources of variation. Dual response plus propagation of error (POE) provides a more useful model of overall response variation. In our case, we implemented this technique in predicting compressive strength of concrete of 28 days in age. Since 28 days is quite time consuming, while it is important to ensure the quality control process. This paper investigates the potential of using design of experiments (DOE-RSM) to predict the compressive strength of concrete at 28th day. Data used for this study was carried out from experiment schemes at university of Benghazi, civil engineering department. A total of 114 sets of data were implemented. ACI mix design method was utilized for the mix design. No admixtures were used, only the main concrete mix constituents such as cement, coarse-aggregate, fine aggregate and water were utilized in all mixes. Different mix proportions of the ingredients and different water cement ratio were used. The proposed mathematical models are capable of predicting the required concrete compressive strength of concrete from early ages.

Keywords: mix proportioning, response surface methodology, compressive strength, optimal design

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Authors: Jung-Il Suh, Hong-Gun Park, Jae-Eun Oh

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Recently, the use of long-span precast concrete (PC) construction has increased in modular construction such as storage buildings and parking facilities. When applying long span PC member, reducing weight of long span PC member should be conducted considering lifting capacity of crane and self-weight of PC member and use of structural lightweight concrete made by lightweight aggregate (LWA) can be considered. In the process of lightweight concrete production, segregation and bleeding could occur due to difference of specific gravity between cement (3.3) and lightweight aggregate (1.2~1.8) and reducing weight of binder is needed to prevent the segregation between binder and aggregate. Also, lightweight precast concrete made by cementitious materials such as fly ash and ground granulated blast furnace (GGBFS) which is lower than specific gravity of cement as a substitute for cement has been studied. When only using fly ash for cementless binder alkali-activation of fly ash is most important chemical process in which the original fly ash is dissolved by a strong alkaline medium in steam curing with high-temperature condition. Because curing condition is similar with environment of precast member production, additional process is not needed. Na-based chloride generally used as a strong alkali activator has a practical problem such as high pH toxicity and high manufacturing cost. Instead of Na-based alkali activator calcium hydroxide [Ca(OH)2] and sodium hydroxide [Na2CO3] might be used because it has a lower pH and less expensive than Na-based alkali activator. This study explored the influences on Ca(OH)2-Na2CO3-activated fly ash system in its microstructural aspects and strength and permeability using powder X-ray analysis (XRD), thermogravimetry (TGA), mercury intrusion porosimetry (MIP). On the basis of microstructural analysis, the conclusions are made as follows. Increase of Ca(OH)2/FA wt.% did not affect improvement of compressive strength. Also, Ca(OH)2/FA wt.% and Na2CO3/FA wt.% had little effect on specific gravity of saturated surface dry (SSD) and absolute dry (AD) condition to calculate water absorption. Especially, the binder is appropriate for structural lightweight concrete because specific gravity of the hardened paste has no difference with that of lightweight aggregate. The XRD and TGA/DTG results did not present considerable difference for the types and quantities of hydration products depending on w/b ratio, Ca(OH)2 wt.%, and Na2CO3 wt.%. In the case of higher molar quantity of Ca(OH)2 to Na2CO3, XRD peak indicated unreacted Ca(OH)2 while DTG peak was not presented because of small quantity. Thus, presence of unreacted Ca(OH)2 is too small quantity to effect on mechanical performance. As a result of MIP, the porosity volume related to capillary pore depends on the w/b ratio. In the same condition of w/b ratio, quantities of Ca(OH)2 and Na2CO3 have more influence on pore size distribution rather than total porosity. While average pore size decreased as Na2CO3/FA w.t% increased, the average pore size increased over 20 nm as Ca(OH)2/FA wt.% increased which has inverse proportional relationship between pore size and mechanical properties such as compressive strength and water permeability.

Keywords: Ca(OH)2, compressive strength, microstructure, fly ash, Na2CO3, water absorption

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Authors: Nani Mchedlishvili, Nino Omiadze, Marine Abutidze, Jose Neptuno Rodriguez-Lopez, Tinatin Sadunishvili, Nikoloz Pruidze, Giorgi Kvesitadze

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Recently, there is an increased interest in the development of food natural colorants as alternatives to synthetic dyes because of both legislative action and consumer concern. Betalains are widely used in the food industry as an alternative of synthetic colorants. The interest of betalains are caused not only by their coloring effect but also by their beneficial properties. The aim of the work was to study of stability of crude and purified red pigments of pokeberry (Phytolacca america L.). The pokeberry fruit juice was filtrated and concentrated by rotary vacuum evaporator up to 25% and the concentrated juice was passed through the Sepadex-25(fine) column (20×1.1 cm). From the column the pigment elution rate was 18 ml/hr. 1.5ml fractions of pigment were collected. In the fractions the coloring substances were determined using CuS04 x 7 H2O as a standard. From the Sephadex G-25 column only one fraction of the betalain red pigment was eluted with the absorption maximum at 538 nm. The degree of pigment purification was 1.6 and pigment yield from the column was 15 %. It was shown that thermostability of pokeberry fruit red pigment was significantly decreased after the purification. For example, during incubation at 100C for 10 min crude pigment retained 98 % of its color while under the same conditions only 72% of the color of purified pigment was retained. The purified pigment was found to be characterized by less storage stability too. The storage of the initial crude juice and the pigment fraction obtained after the gelfiltration for 10 days at 4°C showed the lost of color by 29 and 74 % respectively. From the results obtained, it can be concluded that during the gelfiltration the pokeberry fruit red pigment gets separated from such substances that cause its stabilization in the crude juice.

Keywords: betalains, gelfiltration, pokeberry fruit, stability

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Authors: Louis Nahimana

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Most maps are in a raster or pdf format and it is not easy to get vector layers of published maps. Faced to the production of geological simplified map of the northern Lake Tanganyika countries without geological information in vector format, I tried a method of obtaining vector layers from raster layers created from geological maps of Rwanda and DR Congo in pdf and jpg format. The procedure was as follows: The original raster maps were georeferenced using ArcGIS10.2. Under Adobe Photoshop, map areas with the same color corresponding to a lithostratigraphic unit were selected all over the map and saved in a specific raster layer. Using the same image processing software Adobe Photoshop, each RGB raster layer was converted in grayscale type and improved before importation in ArcGIS10. After georeferencing, each lithostratigraphic raster layer was transformed into a multitude of polygons with the tool "Raster to Polygon (Conversion)". Thereafter, tool "Aggregate Polygons (Cartography)" allowed obtaining a single polygon layer. Repeating the same steps for each color corresponding to a homogeneous rock unit, it was possible to reconstruct the simplified geological constitution of Rwanda and the Democratic Republic of Congo in vector format. By using the tool «Append (Management)», vector layers obtained were combined with those from Burundi to achieve vector layers of the geology of the « Northern Lake Tanganyika countries ».

Keywords: creating raster layer under image processing software, raster to polygon, aggregate polygons, adobe photoshop

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Authors: Michael Russelle S. Alvarez, Noel S. Quiming, Francisco M. Heralde

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This study aims to: a) obtain ethanolic (95% EtOH) and aqueous extracts of Selaginella elmeri, Christella dentata, Elatostema sinnatum, Curculigo capitulata, Euphorbia hirta, Murraya koenigii, Alpinia speciosa, Cymbopogon citratus, Eucalyptus globulus, Jatropha curcas, Psidium guajava, Gliricidia sepium, Ixora coccinea and Capsicum frutescens and screen them for larvicidal activities against Aedes aegypti (Linn.) and Aedes albopictus (Skuse) larvae; b) to fractionate the most active extract and determine the most active fraction; c) to determine the larvicidal properties of the most active extract and fraction against by computing their percentage mortality, LC50, and LC90 after 24 and 48 hours of exposure; and d) to determine the nature of the components of the active extracts and fractions using phytochemical screening. Ethanolic (95% EtOH) and aqueous extracts of the selected plants will be screened for potential larvicidal activity against Ae. aegypti and Ae. albopictus using standard procedures and 1% malathion and a Piper nigrum based ovicide-larvicide by the Department of Science and Technology as positive controls. The results were analyzed using One-Way ANOVA with Tukey’s and Dunnett’s test. The most active extract will be subjected to partial fractionation using normal-phase column chromatography, and the fractions subsequently screened to determine the most active fraction. The most active extract and fraction were subjected to dose-response assay and probit analysis to determine the LC50 and LC90 after 24 and 48 hours of exposure. The active extracts and fractions will be screened for phytochemical content. The ethanolic extracts of C. citratus, E. hirta, I. coccinea, G. sepium, M. koenigii, E globulus, J. curcas and C. frutescens exhibited significant larvicidal activity, with C. frutescens being the most active. After fractionation, the ethyl acetate fraction was found to be the most active. Phytochemical screening of the extracts revealed the presence of alkaloids, tannins, indoles and steroids. A formulation using talcum powder–300 mg fraction per 1 g talcum powder–was made and again tested for larvicidal activity. At 2 g/L, the formulation proved effective in killing all of the test larvae after 24 hours.

Keywords: larvicidal activity screening, partial purification, dose-response assay, capsicum frutescens

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Authors: Thamer Kubat, Riadh Al-Mahaidi, Ahmad Shayan

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The alkali-aggregate reaction (AAR) in concrete has a negative influence on the mechanical properties and durability of concrete. Confinement by carbon fibre-reinforced polymer (CFRP) is an effective method of treatment for some AAR-affected elements. Eighteen reinforced columns affected by different levels of expansion due to AAR were confined using CFRP to evaluate the effect of expansion level on confinement efficiency. Strength and strain capacities (axial and circumferential) were measured using photogrammetry under uniaxial compressive loading to evaluate the efficiency of CFRP wrapping for the rehabilitation of affected columns. In relation to uniaxial compression capacity, the results indicated that the confinement of AAR-affected columns by one layer of CFRP is sufficient to reach and exceed the load capacity of unaffected sound columns. Parallel to the experimental study, finite element (FE) modeling using ATENA software was employed to predict the behavior of CFRP-confined damaged concrete and determine the possibility of using the model in a parametric study by simulating the number of CFRP layers. A comparison of the experimental results with the results of the theoretical models showed that FE modeling could be used for the prediction of the behavior of confined AAR-damaged concrete.

Keywords: carbon fiber reinforced polymer (CFRP), finite element (FE), ATENA, confinement efficiency

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Authors: S. B. Shahmarova, F. N. Iskandarli, J. T. Zeynalov, F. N. Mammadov, M. M. Mirzayev, F. Y. Bayramov

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The physical, mechanical, and chemical properties of aggregates play an important role in the production of ready-mixed concrete. Furthermore, the alkali-silicate reaction of aggregates is one of the essential factors in construction projects for the durability and longer service life of buildings and construction structures to be built. It is necessary to use the aggregates from the liberated regions of Karabakh and East Zangazur in the preparation of concretes to be produced for reconstruction and renovation projects in those regions. In this regard, the study of the physical and mechanical properties of aggregates in the regions around the Araz River (Fuzuli, Jabrayil, and Zangilan) became a significant issue. So, gravel samples were taken from seven different sources located in the regions around Araz River, where the quarries are planned to be built. The chemical oxide composition of the samples was determined, water absorption and specific gravity tests, chloride, alkali-silicate reaction tests, aggregate crushing strength test, Los Angeles, and frost resistance (into the solution of MgSO₄ and Na₂SO₄) tests were performed, and the results were evaluated in accordance with the relevant standards. As a result, it was determined that the aggregates in the regions around the Araz River (Fuzuli, Jabrayil, and Zangilan) conform to the relative standards and can be used effectively in the production of various concretes to be used for the projects in Karabakh.

Keywords: aggregates of the regions around Araz River (Fuzuli, Jabrayil, and Zangilan), physical and mechanical properties, alkali-silicate reaction, Karabakh, Azerbaijan

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Authors: Sharon N. Nuñal, May Flor S. Muegue, Nizzy Hope N. Cartago, Raymund B. Parcon, Sheina B. Logronio

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The antioxidant and anti-inflammatory potentials of Perna Viridis, Modiolus philippinarum, and Mytella charruana found in the Philippines were assessed. Mussel protein samples were hydrolyzed using trypsin, maturase, alcalase and pepsin at 1% and 2% concentrations and then fractionated through membrane filtration (<10 kDa and <30 kDa). Antioxidant assays showed that pepsin hydrolysate at 2% enzyme concentration exhibited the maximum activities for both 2,2-Diphenyl-1-picrylhydrazyl (DPPH) Radical Scavenging Activity (155-176 µM TE/mg protein) and 2,2-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging (67-68 µM TE/mg protein) assays while trypsin hydrolysate dominated the Ferric Reducing Antioxidant Power (FRAP) for the three mussel species. Lower molecular weight peptide fractions at <10 kDa exhibited better antioxidant activities than the higher molecular weight fractions. The anti-inflammatory activities of M. philippinarum and M. charruana showed comparable protein denaturation inhibition potentials with the highest in P. Viridis samples (98.93%). The 5-Lipoxygenase (5-LOX) inhibitory activities of mussel samples showed no significant difference with inhibition exceeding 70%. P. Viridis demonstrated the highest inhibition against Cyclooxygenase-2 (COX-2) at 56.19%, while the rest showed comparable activities. This study showed that the three mussel species are potential sources of bioactive peptides and lipids with antioxidant and anti-inflammatory properties.

Keywords: anti-inflammatory, antioxidant, bioactive properties, mussel

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Authors: Esra Arici, Duygu Olmez, Murat Ozkan, Nurcan Topcu, Furkan Capraz, Gokhan Deniz, Arman Altinyay

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Engineered quartz stone is a composite material comprising approximately 90 wt.% fine quartz aggregate with a variety of particle size ranges and `10 wt.% unsaturated polyester resin (UPR). In this study, the objective is to investigate the influence of particle size distribution on mechanical strength and physical properties of the engineered stone slabs. For this purpose, granular quartz with two particle size ranges of 63-200 µm and 100-300 µm were used individually and mixed with a difference in ratios of mixing. The void volume of each granular packing was measured in order to define the amount of filler; quartz powder with the size of less than 38 µm, and UPR required filling inter-particle spaces. Test slabs were prepared using vibration-compression under vacuum. The study reports that both impact strength and flexural strength of samples increased as the mix ratio of the particle size range of 63-200 µm increased. On the other hand, the values of water absorption rate, apparent density and abrasion resistance were not affected by the particle size distribution owing to vacuum compaction. It is found that increasing the mix ratio of the particle size range of 63-200 µm caused the higher porosity. This led to increasing in the amount of the binder paste needed. It is also observed that homogeneity in the slabs was improved with the particle size range of 63-200 µm.

Keywords: engineered quartz stone, fine quartz aggregate, granular packing, mechanical strength, particle size distribution, physical properties.

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Authors: M. Riazat, H. Abdolvand, M. Baniassadi

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In this present work, 3D reconstruction of cathode of SOFC is developed with various volume fractions and porosity. Three Phase Boundary (TPB) of construction of such derived micro structures is calculated. The neural network is used to optimize the porosity and volume fraction of each phase to reach a structure with maximum TPB.

Keywords: fuel cell, solid oxide, TPB, 3D reconstruction

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Authors: Asma Mosbah, Hanane Khither, Kamelia Mosbah, Noreddine Kacem Chaouche, Mustapha Benboubetra

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In the present investigation, total oil (TO) and its neutral lipid fraction (NLF) extracted from the seed of the well know studied medicinal plant Nigella sativa were tested for their therapeutically effect on alcohol-induced liver injury in rat model. Male Albino rats were divided into five groups of eight animals each and fed a Lieber–DeCarli liquid diet containing 5% ethanol for experimental groups and dextran for control group, for a period of six weeks. Afterwards, rats received, orally, treatments with Nigella sativa extracts (TO, NLF) and N- acetylcysteine (NAC) as a positive control for four weeks. Activities of antioxidant enzymes; superoxide dismutase (SOD) and catalase (CAT), as well as malondialdehyde (MDA) and reduced glutathione (GSH). Biochemical parameters for kidney and liver functions, in treated and non treated rats, were evaluated throughout the time course of an experiment. Liver histological changes were taken into account. Enzymatic activities of both SOD and CAT increased significantly in rats treated with NLF and TO. While MDA level decreased in TO and NLF treated rats, GSH level increased significantly in TO and NLF treated rats. We noted equally a decrease in liver enzymes AST, ALT, and ALP. Microscopic observation of slides from the liver of ethanol treated rats showed a severe hepatotoxicity with lesions. Treatment with fractions leads to an improvement in liver lesions and a marked reduction in necrosis and infiltration. As a conclusion, both extracts of Nigella sativa seeds, TO and NLF, possess an important therapeutic protective potential against ethanol-induced hepatotoxicity in rats.

Keywords: alcohol-induced hepatotoxicity, antioxidant enzymes, Nigella sativa seeds, oil fractions

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Authors: Sung Uk Park, Young Su Kang, Sangmo Kang, Young Kweon Suh

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Mineral product, waste concrete (fine aggregates), waste in the optical field, industry, and construction employ separators to separate solids and classify them according to their size. Various sorting machines are used in the industrial field such as those operating under electrical properties, centrifugal force, wind power, vibration, and magnetic force. Study on separators has been carried out to contribute to the environmental industry. In this study, we perform CFD analysis for understanding the basic mechanism of the separation of waste concrete (fine aggregate) particles from air with a machine built with a rotor with blades. In CFD, we first performed two-dimensional particle tracking for various particle sizes for the model with 1 degree, 1.5 degree, and 2 degree angle between each blade to verify the boundary conditions and the method of rotating domain method to be used in 3D. Then we developed 3D numerical model with ANSYS CFX to calculate the air flow and track the particles. We judged the capability of particle separation for given size by counting the number of particles escaping from the domain toward the exit among 10 particles issued at the inlet. We confirm that particles experience stagnant behavior near the exit of the rotating blades where the centrifugal force acting on the particles is in balance with the air drag force. It was also found that the minimum particle size that can be separated by the machine with the rotor is determined by its capability to stay at the outlet of the rotor channels.

Keywords: environmental industry, separator, CFD, fine aggregate

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Authors: Manuel Rosales, Francisco Agrela, Julia Rosales

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The development of concrete pavements that include recycled waste with active and predictive safety features is a possible approach to mitigate the harmful impacts of the construction industry, such as CO2 emissions and the consumption of energy and natural resources during the construction and maintenance of road infrastructure. This study establishes the basis for formulating new smart materials for concrete pavements and carrying out the in-situ implementation of an experimental road section. To this end, a comprehensive recycled pavement solution is developed that combines eco-hybrid cement made with 25% mixed recycled aggregate powder (pMRA) and biomass bottom ash powder (pBBA) and a 30% substitution of natural aggregate by MRA and BBA. This work is grouped in three lines. 1) construction materials with high rates of use of recycled material, 2) production processes with efficient consumption of natural resources and use of cleaner energies, and 3) implementation and monitoring of road section with sustainable concrete made from waste. The objective of this study is to ensure satisfactory rheology, mechanical strength, durability, and CO2 capture of pavement concrete manufactured from waste and its subsequent application in real road section as well as its monitoring to establish the optimal range of recycled material. The concrete developed during this study are aimed at the reuse of waste, promoting the circular economy. For this purpose, and after having carried out different tests in the laboratory, three mixtures were established to be applied on the experimental road.

Keywords: biomass bottom ash, construction and demolition waste, recycled concrete pavements, full-scale experimental road, monitoring

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Authors: Malleshappa Japagal, Srinivas Chitragar

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The use of waste plastic in pavement is becoming important alternative worldwide for disposal of plastic as well as to improve the stability of pavement and to meet out environmental issues. However, there are still concerns on fatigue and fracture resistance of Hot Mix Asphalt with the addition of plastic waste, (HMA-Plastic mixes) and moisture damage potential. The present study was undertaken to evaluate fracture resistance of HMA-Plastic mixes using semi-circular bending (SCB) test and moisture damage potential by Indirect Tensile strength (ITS) test using retained tensile strength (TSR). In this study, a dense graded asphalt mix with 19 mm nominal maximum aggregate size was designed in the laboratory using Marshall Mix design method. Aggregates were coated with different percentages of waste plastic (0%, 2%, 3% and 4%) by weight of aggregate and performance evaluation of fracture resistance and Moisture damage was carried out. The following parameters were estimated for the mixes: J-Integral or Jc, strain energy at failure, peak load at failure, and deformation at failure. It was found that the strain energy and peak load of all the mixes decrease with an increase in notch depth, indicating that increased percentage of plastic waste gave better fracture resistance. The moisture damage potential was evaluated by Tensile strength ratio (TSR). The experimental results shown increased TRS value up to 3% addition of waste plastic in HMA mix which gives better performance hence the use of waste plastic in road construction is favorable.

Keywords: hot mix asphalt, semi circular bending, marshall mix design, tensile strength ratio

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Authors: Feny Acelia Silaban

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The development of Indonesia’s infrastructure in many islands is significantly increased through the years. Based on this condition, concrete materials which are extracted from natural resources are over exploited and slowly becoming rare, thus the demand for alternative materials becomes so urgently crucial. Oil Palm is one of the biggest commodities in Indonesia with the total amount of 31 million tons in the last 2014. The production of palm oil also generates lots of solid wastes in the form of Oil Palm Shell (OPS). Constructing more environmentally sustainable structures can be achieved by producing lightweight concrete using the Oil Palm Shell (OPS). This paper investigated the effects of OPS and combination of Superplasticizer and fly ash proportion of lightweight concrete mix design to the compressive strength, flexure strength, modulus of elasticity, shrinkage behavior, and water absorption. The Oil Palm Shell had undergone special treatment by washing it with hot water and soap to reduce the oil content. This experiment used four different proportions of Superplasticizer with fly ash and 30 % OPS proportion from the weight of total compositions mixture by the result of trial mix. The experiment result showed that using OPS coarse aggregates and Superplasticizer with fly ash, the average of 28-day compressive strength reached 30-35 MPa. The highest 28-day compressive strength comes from 1.2 % Superplasticizer with 5 % fly ash proportion samples with the strength by 33 MPa. The sample with proportion of 1 % Superplasticizer and 7.5 % fly ash has the highest shrinkage value compared to other proportions. The characteristic of OPS as coarse aggregates is in a standard range of natural coarse aggregates. In general, this lightweight concrete using OPS coarse aggregate and Superplasticizer has high potential to be green-structural lightweight concrete alternative in Indonesia.

Keywords: lightweight concrete, oil palm shell, waste materials, superplasticizer

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Authors: Júlia Cristina Bonaldo, Christophe L. Martin, Martiniano Piccico, Keith Beale, Roop Kishore, Severine Romero-Baivier

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Refractory composite materials employed in steel casting applications are prone to cracking and material damage because of the very high operating temperature (thermal shock) and mismatched properties of the constituent phases. The fracture behavior of a model MgO-C composite refractory is investigated to quantify and characterize its thermal shock resistance, employing a cold crushing test and Brazilian test with fractographic analysis. The discrete element method (DEM) is used to generate numerical refractory composites. The composite in DEM is represented by an assembly of bonded particle clusters forming perfectly spherical aggregates and single spherical particles. For the stresses to converge with a low standard deviation and a minimum number of particles to allow reasonable CPU calculation time, representative volume element (RVE) numerical packings are created with various numbers of particles. Key microscopic properties are calibrated sequentially by comparing stress-strain curves from crushing experimental data. Comparing simulations with experiments also allows for the evaluation of crack propagation, fracture energy, and strength. The crack propagation during Brazilian experimental tests is monitored with digital image correlation (DIC). Simulations and experiments reveal three distinct types of fracture. The crack may spread throughout the aggregate, at the aggregate-matrix interface, or throughout the matrix.

Keywords: refractory composite, fracture mechanics, crack propagation, DEM

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Authors: Micah Amd

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Preferences towards unfamiliar drink brands can be predictably influenced following correlations of subliminally-presented brands (CS) with positively valenced attributes (US). Alternatively, evaluations towards subliminally-presented CS may be more variable, suggesting that CS-evoked evaluations may disassociate from CS-associated preferences following subliminal CS-US conditioning. We assessed this hypothesis over three experiments (Ex1, Ex2, Ex3). Across each experiment, participants first provided preferences and evaluations towards meaningless trigrams (CS) as a baseline, followed by conditioning and a final round of preference and evaluation measurements. During conditioning, four pairs of subliminal and supraliminal/visible CS were respectively correlated with four US categories varying along aggregate valence (e.g., 100% positive, 80% positive, 40% positive, 0% positive – for Ex1 and Ex2). Across Ex1 and Ex2, presentation durations for subliminal CS were 34 and 17 milliseconds, respectively. Across Ex3, aggregate valences of the four US categories were altered (75% positive, 55% positive, 45% positive, 25% positive). Valence across US categories was manipulated to address a supplemental query of whether US-to-CS valence transfer was summative or integrative. During analysis, we computed two sets of difference scores reflecting pre-post preference and evaluation performances, respectively. These were subjected to Bayes tests. Across all experiments, results illustrated US-to-CS valence transfer was most likely to shift evaluations for visible CS, but least likely to shift evaluations for subliminal CS. Alternatively, preferences were likely to shift following correlations with single-valence categories (e.g., 100% positive, 100% negative) across both visible and subliminal CS. Our results suggest that CS preferences can be influenced through subliminal conditioning even as CS evaluations remain unchanged, supporting our central hypothesis. As for whether transfer effects are summative/integrative, our results were more mixed; a comparison of relative likelihoods revealed that preferences are more likely to reflect summative effects whereas evaluations reflect integration, independent of visibility condition.

Keywords: subliminal conditioning, evaluations, preferences, valence transfer

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Authors: Arjun, Gautam, Sanjeev Naval

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Concrete technology has been changing rapidly and constantly since its discovery. Concrete is the most widely used man-made construction material, versatility of making concrete is the 2nd largest consumed material on earth. In this paper an effort has been made to use metal aggregates in concrete has been discussed, the metal aggregates has been named as “BAUT” which had outstandingly qualities to resist shear, tension and compression forces. In this paper, COARSE BAUT AGGREGATES (C.B.A.) 10mm & 20mm and FINE BAUT AGGREGATES (F.B.A.) 3mm were divided and used for making high performance concrete (H.P.C). This “BAUT” had cutting edge technology through draft and design by the use of Auto CAD, ANSYS software can be used effectively In this research paper we study high performance concrete (H.P.C) with “BAUT” and consider the grade of M65 and finally we achieved the result of 90-95 Mpa (high compressive strength) for mega structures and irregular structures where center of gravity (CG) is not balanced. High Performance BAUT Concrete is the extraordinary qualities like long-term performance, no sorptivity by BAUT AGGREGATES, better rheological, mechanical and durability proportion that conventional concrete. This high strength BAUT concrete using “BAUT” is applied in the construction of mega structure like skyscrapers, dam, marine/offshore structures, nuclear power plants, bridges, blats and impact resistance structures. High Performance BAUT Concrete which is a controlled concrete possesses invariable high strength, reasonable workability and negligibly permeability as compare to conventional concrete by the mix of Super Plasticizers (SMF), silica fume and fly ash.

Keywords: BAUT, High Strength Concrete, High Performance Concrete, Fine BAUT Aggregate, Coarse BAUT Aggregate, metal aggregates, cutting edge technology

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Authors: Bander Alzahrani

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Information-centric networking (ICN) using architectures such as Publish-Subscribe Internet Routing Paradigm (PSIRP) is one of the promising candidates for a future Internet, has recently been under the spotlight by the research community to investigate the possibility of redesigning the current Internet architecture to solve many issues such as routing scalability, security, and quality of services issues.. The Bloom filter-based forwarding is a source-routing approach that is used in the PSIRP architecture. This mechanism is vulnerable to brute force attacks which may lead to denial-of-service (DoS) attacks. In this work, we present a new forwarding approach that keeps the advantages of Bloom filter-based forwarding while mitigates attacks on the forwarding mechanism. In practice, we introduce a special type of forwarding nodes called Edge-FW to be placed at the edge of the network. The role of these node is to add an extra security layer by validating and inspecting packets at the edge of the network against brute-force attacks and check whether the packet contains a legitimate forwarding identifier (FId) or not. We leverage Certificateless Aggregate Signature (CLAS) scheme with a small size of 64-bit which is used to sign the FId. Hence, this signature becomes bound to a specific FId. Therefore, malicious nodes that inject packets with random FIds will be easily detected and dropped at the Edge-FW node when the signature verification fails. Our preliminary security analysis suggests that with the proposed approach, the forwarding plane is able to resist attacks such as DoS with very high probability.

Keywords: bloom filter, certificateless aggregate signature, denial-of-service, information centric network

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Authors: M. K. Mzuza, W. Zhang, L. S. Chapola, M. Tembo

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Shire River is the largest and longest river in Malawi emptying its water into the Zambezi River in Mozambique. Siltation is now a major problem in the Shire River due to catchment degradation. This study analysed soil samples from tributaries of the Shire River to determine sources of sediments that cause siltation using the mineral magnetic approach. Bulk sediments and separated particle size fractions of representative samples were collected from tributaries on the western and eastern sides of the Shire River, and Nkula Dam. Eastern tributaries showed relatively higher ferrimagnetic mineral contents and ferrimagnetic to anti ferromagnetic ratios than western tributaries. Sediments from both sides of the Shire River were distinguished by χARM, SIRM versus χlf and S-100 versus SIRM. Findings in this study showed that most of the sediments originated from the western part of the Shire River. Tributaries on the eastern side of the Shire River had higher values for concentration related parameters (χlf, χfd, χARM, SIRM, HIRM, S-100, and χARM/SIRM) than tributaries on the western side. Bulky and detailed magnetic measurements carried out on particle size fractions provided additional confirmation of magnetic contrasts between the two sides of the river suggesting differences in lithology, topography, climate and weather regimes in the catchments. This study demonstrated that the magnetic approach can provide a reliable means of understanding major sediment sources of Nkula Dam and similar situations. It can also help to assess future variations in sediment composition resulting from catchment changes

Keywords: ferrimagnetic minerals, Shire River, tributaries rivers, particle size , topography

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Authors: Hideo Sawada

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Fluoroalkyl end-capped oligomers [RF-(M)n-RF; RF = fluoroalkyl groups; M = radical polymerizable monomers] can form nanometre size-controlled self-assembled oligomeric aggregates through the aggregations of end-capped fluoroalkyl groups. Fluoroalkyl end-capped oligomeric aggregates can also interact with guest molecules to afford fluorinated aggregate/guest molecule nanocomposites; although the corresponding non-fluorinated oligomers cannot form such molecular aggregates to interact with guest molecules. For example, silica nanoparticles should act as guest molecules in fluorinated oligomeric aggregate cores to give new fluorinated oligomer-coated silica nanoparticles (fluorinated oligomer/silica nanocomposites). In these fluoroalkyl end-capped oligomers/silica nanocomposites, some fluorinated oligomers/silica nanocomposites were found to exhibit no weight loss behavior corresponding to the contents of oligomers in the silica matrices even after calcination at 800 oC. Fluoroalkyl end-capped vinyltrimethoxysilane oligomer-coated silica nanoparticles can be prepared by the sol-gel reaction of the corresponding fluorinated oligomer under alkaline conditions. The modified glass surface treated with this fluorinated oligomeric nanoparticle exhibited a completely super-hydrophobic characteristic. These fluorinated nanoparticles were also applied to the surface modification possessing a super-oleophobic characteristic. Not only fluoroalkyl end-capped oligomers but also low molecular weight fluorinated surfactants such as perfluoro-1,3-propanedisulfonic acid (PFPS) were applied to the preparation of fluorinated surfactants/silica nanocomposites to give no weight loss in proportion to the content of the surfactants in the nanocomposites even after calcination at 800 oC.

Keywords: fluorinated oligomer, silica nanocomposite, nonflammable characteristic, superamphiphobic chracteristic

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Authors: Issam A. Al-Khatib

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In order to achieve a significant reduction of waste amount flowing into landfills, it is important to first understand the composition of the solid municipal waste generated. Hence a detailed analysis of municipal solid waste composition has been conducted in Nablus city. The aim is to provide data on the potential recyclable fractions in the actual waste stream, with a focus on the plastic fraction. Hence, waste-sorting campaigns were conducted on mixed waste containers from five districts in Nablus city. The districts vary in terms of infrastructure and average income. The target is to obtain representative data about the potential quantity and quality of household plastic waste. The study has measured the composition of municipal solid waste collected/ transported by Nablus municipality. The analysis was done by categorizing the samples into eight primary fractions (organic and food waste, paper and cardboard, glass, metals, textiles, plastic, a fine fraction (<10 mm), and others). The study results reveal that the MSW stream in Nablus city has a significant bio- and organic waste fraction (about 68% of the total MSW). The second largest fraction is paper and cardboard (13.6%), followed by plastics (10.1%), textiles (3.2%), glass (1.9%), metals (1.8%), a fine fraction (0.5%), and other waste (0.3%). After this complete and detailed characterization of MSW collected in Nablus and taking into account the content of biodegradable organic matter, the composting could be a solution for the city of Nablus where the surrounding areas of Nablus city have agricultural activities and could be a natural outlet to the compost product. Different waste management options could be practiced in the future in addition to composting, such as energy recovery and recycling, which result in a greater possibility of reducing substantial amounts that are disposed of at landfills.

Keywords: developing countries, composition, management, recyclable, waste.

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Authors: W. Mohammed Saeed, A. J. Mcbain, S. M. Cruickshank, C. A. O’Neill

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In the gut, probiotics have been shown to protect epithelial cells from pathogenic bacteria through a number of mechanisms: 1-Increasing epithelial barrier function, 2-Modulation of the immune response especially innate immune response, 3-Inhibition of pathogen adherence and down regulation of virulence factors. Since probiotics have positive impacts on the gut, their potential effects on other body tissues, such as skin have begun to be investigated. The purpose of this project is to characterize the potential of probiotic bacteria lysate as therapeutic agent for preventing or reducing the S. aureus infection. Normal human primary keratinocytes (KCs) were exposed to S. aureus (106/ml) in the presence or absence of L. rhamnosus GG lysate (extracted from 108cfu/ml). The viability of the KCs was measured after 24 hours using a trypan blue exclusion assay. When KCs were treated with S aureus alone, only 25% of the KCs remained viable at 24 hours post infection. However, in the presence of L. rhamnosus GG lysate the viability of pathogen infected KCs increased to 58% (p=0.008, n=3). Furthermore, when KCs co-exposed, pre- exposed or post-exposed to L. rhamnosus GG lysate, the viability of the KCs increased to ≈60%, the L. rhamnosus GG lysate was afforded equal protection in different conditions. These data suggests that two possible separate mechanisms are involved in the protective effects of L. rhamnosus GG such as reducing S. aureus growth, or inhibiting of pathogenic adhesion. Interestingly, a lysate of L rhamnosus GG provided significant reduction in S. aureus growth and adhesion of S. aureus that being viable following 24 hours incubation with S aureus. Therefore, a series of Liquid Chromatography (RP-LC) methods were adopted to partially purify the lysate in combination with functional assays to elucidate in which fractions the efficacious molecules were contained. In addition, the Mass Spectrometry-based protein sequencing was used to identify putative proteins in the fractions. The data presented from purification process demonstrated that L. rhamnosus GG lysate has the potential to protect keratinocytes from the toxic effects of the skin pathogen, S. aureus. Three potential mechanisms were identified: inhibition of pathogen growth; competitive exclusion; and displacement of the pathogen from keratinocyte binding sites. In this study, ‘moonlight’ proteins were identified in the current study’s MS/MS data for L. rhamnosus GG lysate, which could elucidate the ability of lysate in the competitive exclusion and displacement of S. aureus from keratinocyte binding sites. Taken together, it can be speculated that L. rhamnosus GG lysate utilizes different mechanisms to protect keratinocytes from S. aureus toxicity. The present study indicates that the proteinaceous substances are involved in anti-adhesion activity. This is achieved by displacing the pathogen and preventing the severity of pathogen infection and the moonlight proteins might be involved in inhibiting the adhesion of pathogens.

Keywords: lysate, fractions, adhesion, L. rhamnosus GG, S. aureus toxicity

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Authors: Ozlem Bahadir Acikara, Mert Ilhan, Ekin Kurtul, Karel Smejkal, Esra Kupeli Akkol

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Present study is aimed to investigate in vitro inhibitory effects of the extracts prepared from the aerial parts of Podospermum canum (Asteraceae) on hyaluronidase, collagenase, and elastase enzymes using a bioassay-guided fractionation. Inhibitory effects of the extract, sub-extracts, fractions obtained by column chromatography, and isolated compounds on collagenase, elastase, and hyaluronidase were performed by using in vitro enzyme inhibitory assays based on spectrophotometric evaluation. The ethyl acetate and remaining water extracts prepared from the plant displayed significant inhibitory activities on collagenase and elastase, while petroleum ether and chloroform extracts did not show any inhibitory activity. Eleven known compounds: arbutin, 6'-O-caffeoylarbutin, cichoriin, 3,5-dicaffeoylquinic acid methyl ester, apigenin-7-O-β-glucoside, luteolin-7-O-β-glucoside, apigenin-7-O-β-rutinoside, isoorientin, orientin, vitexin, procatechuic acid, and compound 4-hydroxy-benzoic acid 4-(6-O-α-rhamnopyranosyl-β-glucopyranosyl) benzyl ester have been obtained from ethyl acetate sub-extract of the plant through bioassay-guided fractionation and isolation. Results of the present study have revealed that among the isolated compounds, apigenin-7-O-β-glucoside, luteolin-7-O-β-glucoside, apigenin-7-O-β-rutinoside and isoorientin showed potent enzyme inhibitory activities. However, methanolic extract of P. canum displayed a greater inhibitory activity than fractions and isolated compounds both on collagenase and elastase.

Keywords: Asteraceae, collagenase, elastase, hyaluronidase, Podospermum canum

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