Original Filler Research Articles

Effect of Sulfur Autotrophic Denitrification Sludge on the Start-Up Characteristics of Anaerobic Ammonia Oxidation

In this study, we used a two-stage experiment in order to investigate the effect of the inoculation with elemental sulfur-based autotrophic denitrification (S0-SADN) sludge on the start-up characteristics of Anaerobic ammonia oxidation (ANAMMOX). In the first stage, we attempted direct enrichment with an elemental sulfur and pyrite filler in a S0-SADN reactor, which retained stable operation, and adjusted the nitrogen source components of the influent at different times. In the second stage, we replaced the original filler with Kaldnes filler, and set the influent component to be divided into NH4+-N and NO2−-N. The ANAMMOX process could not be started in the 80-day S0-SADN stage despite the 0.8% abundance of Candidatus Kuenenia; however, after changing the original filler, the reactor showed obvious ANAMMOX reaction characteristics after day 44, and under the condition of an influent TIN load of 0.36 kg(m3·d)−1, the reactor TIN removal rate was stable at more than 80% after day 55. The main ANAMMOX bacteria in the reactor were Candidatus Brocadia (1.08%) and Candidatus Kuenenia (0.96%). The results show that it is feasible to initiate the ANAMMOX process by inoculating the S0-SADN sludge; however, it is not suitable to start the ANAMMOX and the stable operation of the S0-SADN simultaneously. The ANAMMOX process can be started first under the condition of no sulfur source, which takes little time. After initiating the ANAMMOX process, the coupling S0-SADN process can be re-considered given an excessive accumulation of S0-SADN bacteria in the system.

Al2O3 decorated with polyhedral silsesquioxane units: An unconventional filler system for upgrading thermal conductivity and mechanical properties of rubber composites

The present study reports on the development and exploitation of an original filler system, based on alumina nanoparticles (NPs) and polyhedral silsesquioxane (POSS) units, namely Al2O3@POSS, where the remarkable compatibilization and thermomechanical features imparted by the silsesquioxane cage units “makes an alliance” with the enhanced thermal conductivity of Al2O3 NPs. The target is to supply rubber nanocomposites with improved heat transport and mechanical properties potentially applicable in tires formulation.The hybrid filler was prepared by a double-step approach consisting of a first silanization of Al2O3 with a methacrylate silane and subsequent grafting of OctaMethacrylPOSS through a radical reaction mediated by dicumyl peroxide as radical initiator. The material was characterized in depth in terms of structure, surface, and morphology and then used for producing, by solvent-casting technique, polybutadiene composites. The idea is to supply and test a model alumina-rubber based system which allows to better unveil the role played by the silsesquioxane units, thanks to the absence of other components (i.e. rubber polymers, vulcanization curatives and filler) usually included in real rubber formulations for tires.The comprehensive thermomechanical and morphological characterization of the nanocomposites highlighted the key role played by POSS units decorating the alumina surface, which assure both the compatibility between filler and polymer host, and an homogeneous distribution and continuous networking of the alumina NPs. This positively influences not only the heat transport, providing thermal conductive pathways that raise the thermal diffusivity even at low filler loadings (+60–70% with respect to composite enclosing bare alumina at a concentration of 15–10 v/v %) but also the storage modulus, paving the way toward a potential exploitation of Al2O3@POSS hybrid filler in large-scale formulations of rubber composites, namely those employed for tires.

Green Building Materials Based on Waste Filler and Binder

Abstract This study is aimed at the application of alternative binder (AB) into bio-aggregate-based composite. The technically important parameters (density, thermal conductivity, water absorption and compressive strength) of 28, 60 and 90 days hardened green composites containing chemically and physico-chemically modified hemp hurds (HH) with AB compared to the Portland cement (PC) are presented. Testing of two reference bio-composites with original HH confirmed higher values of compressive strength and thermal conductivity unlike water absorption for all hardened specimens based on alternative binder (MgO-cement) compared to conventional PC. Changes in the final properties of hardened bio-composites were affected by treatment process of organic filler and alkaline nature of MgO-cement. The combination of purified HH by ultrasound treatment and AB appears to be promising for preparation of bio-based composite material with better properties compared to PC. In this paper, other option of the preparation of bio-composite system based on original (non-treated) filler and binder consisting of optimal activated MgO and silica fume is presented.

Optimization of replacement fines in roads base materials by cement/ lime

The road networks in Iraq suffer from the increase in the proportion of highly carriage trucks and vehicle growth rates, which requires improving the layer’s characteristics and using protective methods accomplished with suitable costs to achieve high quality and fewer cost treatments. This paper investigates the effect of modifying sand -gravel soil as a base layer by using cement or/ lime as a replacement to the original filler. The mechanical properties of the mix were evaluated based on compaction, CBR, and compression strength tests. The results for the CBR test suggested that there was an increase in bearing ratio when replacing a percent of filler by cement or lime as compared with the origin material, and the percent of replacement by cement or lime was 30% of origin filler. The results for the compression strength show that there is an increase with increasing percent of filler replacement by Cement, on the contrary, the Lime increase reveals a decrease in strength. The replacement with cement was better than that of lime. Lime should be used in less than 30% from point of view cost and strength. The findings of this paper suggested that adopting the method will result in decreasing the thickness of the pavement layer. The best results obtained when adopting 100% replacement by cement (10% by total weight) which gave the best reduction in the required thickness by about 62%. Regarding the lime use, the results revealed optimal percent of lime to be used is about 3% of total weight.

Preparation of flexible transparent acryl/alumina nano-hybrid materials exhibiting low thermal expansion coefficient

In this study, flexible transparent hybrid films with low thermal expansion coefficient were prepared by combination of alumina fillers and polymerizable/non-polymerizable surface modifiers with carboxyl group. Four types of alumina fillers with different shape and size were used in this study, and could modify with surface modifiers containing carboxyl groups by electrostatic interaction and disperse homogeneously in resulting hybrid films regardless of the shape and size. So the hybrid films obtained showed high transmittance around 90%T, and it was considered, from transmission electron microscopic analysis, alumina fillers were dispersed at near original filler size, without aggregation. Moreover, thermal mechanical analysis cleared that the use of pillar or fiber type filler is more effective to reduce CTE compared with plate type fillers, especially CTE of hybrid film prepared with fiber type filler was drastically decreased to 17 ppm/K, while the influence by the difference of filler shape/size was not observed on tensile properties, surface hardness. By use of fiber type alumina filler and combination of polymerizable surface modifier and non-polymerizable surface modifier which seems to interact with matrix, for optimizing of the crosslink density, it was possible to reduce CTE, while the good mechanical properties was kept. Finally, hybrid film indicating low CTE value as 19 ppm/K, high flexibility (windable against 0.4 mm radius steel bar), and good tensile properties and surface hardness which were equal to or higher than those of matrix could prepared.

Composites of ionic liquid and amine-modified SAPO 34 improve CO2 separation of CO2-selective polymer membranes

Mixed matrix membranes with ionic liquids and molecular sieve particles had high CO2 permeabilities, but CO2 separation from small gas molecules such as H2 was dissatisfied because of bad interfacial interaction between ionic liquid and molecular sieve particles. To solve that, amine groups were introduced to modify surface of molecular sieve particles before loading with ionic liquid. SAPO 34 was adopted as the original filler, and four mixed matrix membranes with different fillers were prepared on the outer surface of ceramic hollow fibers. Both surface voids and hard agglomerations disappeared, and the surface became smooth after SAPO 34 was modified by amine groups and ionic liquid [P66614][2-Op]. Mixed matrix membranes with composites of amine-modified SAPO 34 and ionic liquid exhibited excellent CO2 permeability (408.9 Barrers) and CO2/H2 selectivity (22.1).

A three-dimensional shape design problem to determine the filler geometry for optimal system thermal conductivity

A three-dimensional shape design problem is considered in this work, based on the desired thermal conductivity ratio and filler volume, to determine the optimal shape of filler between two conductive bodies in a three-dimensional composite material. The Levenberg–Marquardt method (LMM), commercial software CFD-ACE + and B-spline surface generation technique are adopted in the present shape design algorithm. The design analysis is examined using the numerical experiments and different filler volume and thermal conductivity are considered in the numerical test cases to justify the validity of this study. The estimated results obtained with optimal filler are then compared with those using original filler shapes and it is found that (i) the optimal filler shapes are found as a family of “hourglass” shape with a smooth nozzle-diffuser shape in the central parts of filler and (ii) the radiuses of the top and bottom surfaces of filler play the most significant role on the effective thermal conductivity. Besides, by fixing the filler thermal conductivity, the effective thermal conductivities using optimal fillers can be increased from 15.3% to 47.6% depending on different filler volumes and by fixing the filler volume, the effective thermal conductivities using optimal fillers can be increased from 5.5% to 57.4% depending on different filler conductivities.

Resistant Multilayer Floor Systems Based on Epoxy Binders with Recycled Various Glass Particles

The aim of the work was to use common waste glass materials as fillers in polymer resin and to propose the use it for selected multilayer polymer flooring systems which belongs to widespread materials for industrial and also public constructions. Authors decided to use polymer binder based on two different 2-component commercial epoxides Lena N 102 and Lena N 128. Common available secondary materials which replaced original filler were tested in mentioned polymer binder. Tested glass fillers were chosen according its chemical composition and physical properties. Used recycled materials were glass of windscreen, glass beads, screen, glass packaging and fluorescent glass. The filler compatibility with binder matrix was determined according mixture processability, applicability and evaluation of hardened surface.

Grind Cullet and Silicate Coatings

Pursuant to evaluations obtained at solving this topics in 2010, when was successfully supplied filler at acrylate coatings with grind cullet (waste glass), was chosen referential mixtures of silicate coatings with optimum quality. In Those choice mixtures was made a filler modification by various quantity of the cullet. Used cullet is from crushed glass bottle, that can’t be used for recyclation no more. Filler modification was provided so, to the new filler mixtures was approximate to ideal grading curve. The sieve analysis of original filler materials was made and after comparison of the results were proposed mixtures of new modified mixtures of filler. These then was further analysed and modified. The basic characteristic that was on modifying materials monitored belongs to cohesion with basis, consistence, vapour diffusion and smash strength. Considering absence of coatings surface quality classification Methodist in Czech prescriptions, was for the work needs created a personal methodology for classification coatings surface quality classification.

Characterization of High-Frequency Induction Brazed Magnesium Alloy Joint with an Al-Mg-Zn Filler Metal

In this paper, a novel Al-Mg-Zn filler metal was designed to join magnesium alloy AZ31B plates by means of high-frequency induction brazing in argon gas shield condition. The microstructure and the mechanical properties of the brazed joint were investigated. The experimental results showed that the brazed joint contained large amount of α-Mg and β-Mg17(Al, Zn)12 phases. The homogeneous Mg32(Al, Zn)49 phase in the original filler metal was consumed due to the intensive alloying during the brazing process. The results indicate that the shear strength of the brazed joint is 35 MPa. The fracture morphology of the brazed joint exhibits intergranular fracture mode, and the fracture originates from the hard β-Mg17(Al, Zn)12 phase.

Microstructure and Mechanical Properties of Magnesium Alloy AZ31B Brazed Joint Using a Zn-Mg-Al Filler Metal

In order to join the similar magnesium alloy, a novel Zn-Mg-Al filler metal was designed and applied to braze AZ31B plates by using high-frequency induction brazing technique. The microstructure, phase constitution and fracture morphology of the brazed joint were investigated. The experimental results show that MgZn2 phase in the original filler metal is completely consumed in the brazing process. Moreover, α-Mg solid solution and α-Mg+MgZn eutectoid structure formed in the brazing region due to the intensive alloying between the molten filler metal and the base metal in the brazing process. Test results indicate that the shear strength of the brazed joint is 56 MPa. The fracture morphology of the brazed joint shows intergranular fracture mode, where crack originates from the hard α-Mg+MgZn eutectoid structure.

High-frequency induction soldering of magnesium alloy AZ31B using a Zn−Al filler metal

Magnesium alloy AZ31B plates were soldered by means of high-frequency induction soldering using a Zn−Al filler metal in argon gas shield condition. The interfacial microstructure and phase constitution of the soldered joint were investigated. The experimental results show that α-Mg solid solution and α-Mg + MgZn eutectoid structure were formed in soldering region. Moreover, the zinc solid solution and the aluminum solid solution in the original filler metal disappeared completely after the soldering process. Test results indicate that the shear strength of the soldered joint is 19 MPa. The fracture morphology of the soldered joint exhibits intergranular fracture mode and the crack originates from α-Mg + MgZn eutectoid structure.

Polymer nanocomposite materials based on polystyrene and a layered aluminate filler

AbstractExfoliated polystyrene nanocomposites have been synthesized by in situ bulk multistep polymerization of polystyrene (PS) in the presence of the filler. The filler was layered double hydroxide (LDH)–tetracalcium aluminate hydrate, modified by the intercalation of benzoate anions (Ca4Al2(OH)12(C6H5COO)2·xH2O). Benzoate anions were found to increase the interlayer distance of the original filler. At the same time, the organophilicity of the filler was increased. The LDH was prepared using a variant of the rehydration method. The PS/LDH composites were characterized by X‐ray diffraction (XRD), infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis (TGA), and transmission electron microscopy methods. XRD and TGA results pointed to the successful incorporation of the filler within the polymer matrix. However, XRD results indicated that a characteristic layered structure of the filler had disappeared, i.e. the delamination had occurred. The filler was dispersed within the matrix in a form of nanosized monolayer particles, i.e. a nanocomposite material was prepared. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

Effects of Monomer Composition and Original Filler Content on Filler Loading in the Resulting Centrifuged Composites

This study examined the effects of monomer composition, original filler content, and application of centrifugal force on the resulting filler loading of composites. Either Bis-MPEPP or UDMA was mixed with TEGDMA at a molar ratio of 1 : 1. Silane-treated silica (14-20 wt%) was added to each mixture. After the mixtures were centrifuged and light-polymerized, rate of increase was determined as the filler increment of 2.0-mm-high, disk-shaped sections of specimen when compared against the uncentrifuged filler content. Both the original filler loading and monomer composition influenced the filler content of the centrifuged composites. Fillers in Bis-MPEPP-based composites exhibited a higher rate of condensation after application of centrifugal force than did UDMA-based composites. The results were suggestive of underlying relationships among the composition, component stability, and post-polymerization properties of flowable composites.

Work of adhesion influence on the rheological properties of silica filled polymer composites

As the work of adhesion, Wa, increases between a silica filler surface and a polymer matrix, the dynamic viscosity and the shear modulus of the composite material increase. The logarithms of these properties decrease linearly as Wa decreases. At lower dynamic test frequencies, a change in Wa has a more dramatic impact on these properties than at higher frequencies. An “effective silica particle size” model can be used to explain why Wa affects the viscosity and the shear modulus of a composite. According to that model, the thickness of the interphase layer increases as the Wa increases. An increase in effective particle size decreases the “free” polymer volume, and the decrease free volume polymer causes both the viscosity and the shear modulus to increase. Increasing the dynamic test frequency releases some of the immobilized polymer from the filler surface which causes the effective particle size to decrease. As the effective particle size decreases because of the increased testing frequency and approaches the mean size of the original filler, the impact of the Wa value on viscosity and shear modulus should decrease. However, the friction experienced between the filler interphase and the polymer, the so called “skin friction”, depends on the magnitude of Wa and the more general term, bond energy density (BED). The skin friction determines the viscosity of the composite, particularly at lower frequencies. Higher Wa values induce higher skin friction and thereby higher flow resistance (viscosity) as polymer chains move along the filler surface.