Natural Mordenite from Spain as Pozzolana

This work deals with anomalous concentrations of natural mordenite in the southeast of Spain. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies evidenced that the samples contain mainly monomineral zeolitic phase of mordenite (70% to 74%), usually accompanied by smectite (montmorillonite), the principal component of bentonite. A study of the applicability of these zeolites is presented to establish the potential use as pozzolanic cements. For comparative purposes, synthetic commercial mordenite is also characterized and tested. The initial mixtures were prepared using cement and mordenite at a 75:25 ratio. Chemical analysis and a pozzolanicity test showed the high pozzolanic character. These mixtures were further added to sand and water, yielding the cement specimens to be used as concrete. Mechanical test results showed that the mechanical compression at 7 and 28 days fall into the range of 19.23 to 43.05 MegaPascals (MPa) for the cement specimens built with natural mordenites. The obtained results fall in the same range of cement specimens prepared with natural clinoptilolite, using mixtures within the European requirement for commercial concretes. Thus, these results and the low cost of natural mordenite of San José de los Escullos deposit supports the potential use of natural mordenite as pozzolanic cement.

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Transient liquid phase bonding of Cu and Al using metallic particles interlayers

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420988235 ◽

2021 ◽

pp. 095440542098823

Author(s):

Alireza Zaheri ◽

Mohammadreza Farahani ◽

Alireza Sadeghi ◽

Naser Souri

Keyword(s):

Liquid Phase ◽

Mechanical Test ◽

Transient Liquid Phase ◽

Transient Liquid Phase Bonding ◽

Joint Interface ◽

Test Results ◽

X Ray Diffraction ◽

X Ray ◽

Metallic Particles ◽

Powder Interlayer

The bonding strength, and microstructures of Cu and Al couples using metallic powders as interlayer during transient liquid phase bonding (TLP bonding) were investigated. The interfacial morphologies and microstructures were studied by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy, and X-ray diffraction. First, to explore the optimum bonding time and temperature, nine samples were bonded without interlayers in a vacuum condition. Mechanical test results indicated that bonding at 560°C in 20 min returns the highest bond strength (84% of Al). This bonding condition was used to join ten samples with powder interlayers. Powders were prepared by mixing different combinations of Cu, Al (+Fe nanoparticles) and Zn. In the bonding zone, different Cu9Al4, CuAl, and CuAl2 intermetallic co-precipitate. The strongest bonding is formed in the sample with the 70Al (+Fe)-30Cu powder interlayer. Powder interlayers present thinner and more uniform intermetallic layers at the joint interface.

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Effect of Morphology on Near-Infrared Shielding Properties of Aluminum-Doped ZnO by Solvothermal Synthesis

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1007.148 ◽

2020 ◽

Vol 1007 ◽

pp. 148-153

Author(s):

Pimpaka Putthithanas ◽

Supan Yodyingyong ◽

Jeerapond Leelawattanachai ◽

Wannapong Triampo ◽

Noppakun Sanpo ◽

...

Keyword(s):

Near Infrared ◽

Low Cost ◽

Hexagonal Wurtzite Structure ◽

Infrared Region ◽

X Ray Diffraction ◽

Smart Window ◽

Doped Zno ◽

Heat Shielding ◽

Xrd Patterns ◽

Potential Use

In this work, aluminum-doped ZnO (AZO) is synthesized for heat-shielding applications. A family of ethanolamine (EA: monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine TEA)) is used to control the morphology of aluminum-doped ZnO (AZO) synthesized via a simple solvothermal method at the temperature of 120°C for 6 h. The samples were characterized by field-emission scanning electron microscopy (FE-SEM). The formation of primary ZnO nanoparticles (NPs) showed that TEA yielded highly packed-spherical aggregates not found when DEA and MEA were used. X-ray diffraction (XRD) found that all AZO samples have peaks of the ZnO hexagonal wurtzite structure. XRD patterns of aluminum were found for >10 mol%. UV-Vis-NIR spectrophotometer was used to study the optical property and heat-shielding of the near-infrared region (NIR, the wavelength from 700 - 2500 nm). All AZO NPs of 0, 2, 4, and 10 mol% exhibited strong NIR shielding ability up to 80% insulation. From these results, the AZO NPs have potential use as NIR shielding materials of low-cost and simple processes to be coated on an energy-efficient window as smart window coating in buildings and automotive thus reducing energy consumption, especially in air conditioning usage.

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Potential Use of Green Synthesized Al2O3 (Alumina) Nanoparticles from Guava Leaves (Psidium guajava) for the Removal of Methylene Blue from Wastewater

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.23144 ◽

2021 ◽

Vol 33 (6) ◽

pp. 1304-1308

Author(s):

Debasish Mondal ◽

Dipankar Mahata ◽

Kamala Mandy Hansda ◽

Sourav Mondal ◽

Ajit Das

Keyword(s):

Methylene Blue ◽

Low Cost ◽

Xrd Analysis ◽

Psidium Guajava ◽

Alumina Nanoparticles ◽

X Ray Diffraction ◽

Guava Leaves ◽

Al2o3 Nps ◽

Potential Use ◽

Significant Attention

Recently non-harmful nanomaterials have acquired critical significant attention in wastewater treatment containing organic pollutants especially toxic and hazardous dyes. In this regard, a low cost and eco friendly method has been investigated for the green synthesis of alumina nanoparticles (Al2O3 NPs). The alumina nanoparticles were synthesized using an aqueous extract of Psidium guajava leaf as a potential stabilizing agent. The UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) techniques were used to characterize the synthesized nanoparticles. The absorption at 281 nm confirmed the formation of alumina nanoparticles. The FTIR spectra and XRD analysis confirmed the presence of various functional groups and crystalline structures of Al2O3 NPs during the synthesis. The spectrum clearly indicates the organic moieties in Psidium guajava extract are responsible for the biosynthesis of Al2O3 NPs. The suface morphology of Al2O3 NPs was confirmed by SEM and EDS studies. Besides this, the removal of methylene blue through adsorption and kinetic study was also reported.

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Assessing the possibility of solidification and stabilization of pyrite cinder by using quicklime and fly ash

JOURNAL OF ENGINEERING & PROCESSING MANAGEMENT ◽

10.7251/jepm1902122k ◽

2020 ◽

Vol 11 (2) ◽

Author(s):

Đurđa Kerkez ◽

Dragana Tomašević Pilipović ◽

Milena Bečelić‐Tomin ◽

Nataša Slijepčević ◽

Dunja Rađenović ◽

...

Keyword(s):

Fly Ash ◽

Low Cost ◽

Test Results ◽

Pyrite Cinder ◽

X Ray Diffraction ◽

Leaching Behavior ◽

X Ray ◽

Acidic Solutions ◽

Lead And Zinc ◽

Very High

The aim of this study was to determine the possibility of using two low-cost binders,quicklime and fly ash for the solidification/stabilization (S/S) of pyrite cinder.Pyrite cinder, used in this study, represents a remnant from sulfuric acid productionin fertilizer factory IHP “Prahovo” A.D. (Serbia), and has a very high toxicmetal content. High contents and leachability of copper, lead and zinc make thiswaste material hazardous, representing an extraordinary risk to the environment.In order to determine the leaching behavior of the S/S mixtures, four single-stepleaching tests were performed, each one having a different sort of leaching fluid(deionized water, inorganic and organic acidic solutions). X-ray diffraction (XRD),scanning electron microscope (SEM) and energy dispersive X-ray analyzer (EDS)were implemented to elucidate the mechanisms responsible for immobilization ofCu, Pb and Zn. Overall, the test results indicated that S/S treatment using bothquicklime and fly ash was effective in immobilizing these metals, especially whenthere is a higher share of binder present. Treated waste can be safe for disposal andeven considered for “controlled utilization”. Furthermore, the use of fly ash for S/Streatment of pyrite cinder solves the disposal problems of two waste types, as it alsorepresents a secondary industrial product.

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Influence of Wood-Based Biomass Ash Admixing on the Structural, Mechanical, Hygric, and Thermal Properties of Air Lime Mortars

Materials ◽

10.3390/ma12142227 ◽

2019 ◽

Vol 12 (14) ◽

pp. 2227 ◽

Cited By ~ 6

Author(s):

Milena Pavlíková ◽

Lucie Zemanová ◽

Jaroslav Pokorný ◽

Martina Záleská ◽

Ondřej Jankovský ◽

...

Keyword(s):

Building Materials ◽

Mechanical Test ◽

Low Cost ◽

Simultaneous Thermal Analysis ◽

Fluorescence Analysis ◽

X Ray Diffraction ◽

Biomass Ash ◽

X Ray ◽

Binder Ratio ◽

Active Admixture

Mechanically-activated wood-based biomass ash (WBA) was studied as a potential active admixture for design of a novel lime-pozzolan-based mortar for renovation purposes. The replacement ratio of lime hydrate in a mortar mix composition was 5%, 10%, and 15% by mass. The water/binder ratio and the sand/binder ratio were kept constant for all examined mortar mixes. Both binder constituents were characterized by their powder density, specific density, BET (Brunauer–Emmett–Teller), and Blaine specific surfaces. Their chemical composition was measured by X-ray fluorescence analysis (XRF) and mineralogical analysis was performed using X-ray diffraction (XRD). Morphology of WBA was investigated by scanning electron microscopy (SEM) and element mapping was performed using an energy dispersive spectroscopy (EDS) analyzer. The pozzolanic activity of WBA was tested by the Chapelle test and assessment of the Portlandite content used simultaneous thermal analysis (STA). For the hardened mortar samples, a complete set of structural, mechanical, hygric, and thermal parameters was experimentally determined. The mortars with WBA admixing yielded similar or better functional properties than those obtained for traditional pure lime-based plaster, pointing to their presumed application as rendering and walling renovation mortars. As the Chapelle test, STA, and mechanical test proved high pozzolanity of WBA, it was classified as an alternative eco-efficient low-cost pozzolan for use in lime blend-based building materials. The savings in CO2 emissions and energy by the use of WBA as a partial lime hydrate substitute in mortar composition were also highly appreciated with respect to the sustainability of the construction industry.

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Tuning the Morphology in the Nanoscale of NH4CN Polymers Synthesized by Microwave Radiation: A Comparative Study

Polymers ◽

10.3390/polym14010057 ◽

2021 ◽

Vol 14 (1) ◽

pp. 57

Author(s):

Cristina Pérez-Fernández ◽

Pilar Valles ◽

Elena González-Toril ◽

Eva Mateo-Martí ◽

José Luis de la Fuente ◽

...

Keyword(s):

Soft Matter ◽

Compositional Data ◽

Low Cost ◽

Reaction Times ◽

Principal Component ◽

Simultaneous Thermal Analysis ◽

X Ray Diffraction ◽

Reaction Conditions ◽

Thermal Methods ◽

Macromolecular Systems

A systematic study is presented to explore the NH4CN polymerization induced by microwave (MW) radiation, keeping in mind the recent growing interest in these polymers in material science. Thus, a first approach through two series, varying the reaction times and the temperatures between 130 and 205 °C, was conducted. As a relevant outcome, using particular reaction conditions, polymer conversions similar to those obtained by means of conventional thermal methods were achieved, with the advantage of a very significant reduction of the reaction times. The structural properties of the end products were evaluated using compositional data, spectroscopic measurements, simultaneous thermal analysis (STA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). As a result, based on the principal component analysis (PCA) from the main experimental results collected, practically only the crystallographic features and the morphologies in the nanoscale were affected by the MW-driven polymerization conditions with respect to those obtained by classical syntheses. Therefore, MW radiation allows us to tune the morphology, size and shape of the particles from the bidimensional C=N networks which are characteristic of the NH4CN polymers by an easy, fast, low-cost and green-solvent production. These new insights make these macromolecular systems attractive for exploration in current soft-matter science.

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Modification of natural clinoptilolite for the nitrate removal from water media

Journal of the Serbian Chemical Society ◽

10.2298/jsc140116038p ◽

2014 ◽

Vol 79 (10) ◽

pp. 1309-1322 ◽

Cited By ~ 3

Author(s):

Jelena Pavlovic ◽

Jelena Milenkovic ◽

Nevenka Rajic

Keyword(s):

Adsorption Mechanism ◽

Low Cost ◽

Nitrate Removal ◽

X Ray Diffraction ◽

Binding Ability ◽

Modified Zeolite ◽

X Ray ◽

Water Media ◽

Pseudo Second Order ◽

Natural Clinoptilolite

The natural zeolitic tuff from the Zlatokop mine (Vranjska Banja deposit) has been investigated as a starting material for obtaining a low cost adsorbent for the removal of nitrate from water media. The tuff riched with zeolite - clinoptilolite was modified by simple procedures by several oxides: iron(III), manganese(IV) and magnesium in order to make clinoptilolite surface accessible for binding the nitrate ions. The obtained oxide-modified zeolite samples were characterized by scanning electron microscopy and energy dispersive X-ray analysis (SEM/EDS), powder X-ray diffraction (PXRD), infrared spectroscopy (FTIR) and by measurement of specific surface area. The effects of the adsorbent dosage (0.5, 1.0, 1.5 and 2.0 g), temperature (25, 35 and 45 ?C) and initial nitrate concentration (C0= 100, 200 and 300 mg dm-3) on the binding efficiency were also studied. For all adsorbents the efficiency increases with temperature. The type of oxides effects the adsorption mechanism and Fe(III) oxide modified zeolite exhibits the best binding ability. For this adsorbent the adsorption kinetics was studied and found that it is best represented by the pseudo-second-order model.

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Reinforcing Linear Low-Density Polyethylene with Surfactant-Treated Microfibrillated Cellulose

Polymers ◽

10.3390/polym11030441 ◽

2019 ◽

Vol 11 (3) ◽

pp. 441 ◽

Cited By ~ 5

Author(s):

Guangzhao Wang ◽

Xiaohui Yang ◽

Weihong Wang

Keyword(s):

Mechanical Properties ◽

Composite Film ◽

Mechanical Test ◽

Intermolecular Hydrogen Bond ◽

Microfibrillated Cellulose ◽

Light Transmittance ◽

Test Results ◽

X Ray Diffraction ◽

Twin Screw ◽

Ldpe Composites

Due to its excellent mechanical properties and reinforcement abilities, cellulose has become a promising candidate for developing nanocomposites. However, cellulose agglomeration is an issue that must be solved. In this study, we treated microfibrillated cellulose (MFC) with a mixture of the non-ionic surfactants Span80 and Tween80 (ratio of 1:1) in order to prevent the intermolecular hydrogen bond aggregation of MFC during the process of MFC drying. We used a conical twin-screw extruder to melt compounds for the surfactant-treated MFC and powdered LLDPE. Furthermore, the extruded mixture was hot-pressed into a film, and we also tested the properties of the composite film. We can conclude that there was no agglomeration in the composite film according to microscopic observations and light transmittance test results. Furthermore, the dispersion of the surfactant-treated MFC (STMFC) was uniform until the STMFC filler increased to 10 wt%. The mechanical test results show that when the content of STMFC filler was 10 wt%, the mechanical properties of the composite were optimal. Compared to LLDPE, the STMFC/LLDPE composite film had an increase of 41.03% in tensile strength and an increase of 106.35% in Young’s modulus. Under this system, the DSC results show that the melting point of LLDPE increased from 125 to 131 °C. X-ray diffraction (XRD) results showed that the addition of STMFC did not change the crystallinity of the STMFC/LDPE composites, although the crystallite size increased.

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Investigations on corrosion and mechanical properties of a 20 year old ground anchor exhumed at a power station site

Canadian Geotechnical Journal ◽

10.1139/cgj-2015-0387 ◽

2016 ◽

Vol 53 (4) ◽

pp. 589-602 ◽

Cited By ~ 5

Author(s):

Yujie Wang ◽

Aiwu Ren ◽

Yanshu Wang ◽

Jiquan He ◽

Zuyu Chen

Keyword(s):

Mechanical Test ◽

Test Procedure ◽

Test Results ◽

X Ray Diffraction ◽

Tunnel Face ◽

Bonding Force ◽

Laboratory Test Results ◽

Average Corrosion Rate ◽

Chinese Standard ◽

Gradual Release

This paper presents the observed findings and laboratory test results of an anchor exhumed from Manwan Hydropower Station, China, that was installed 20 years ago. The prestressed cables are 25.6 m long with a working load of 1000 kN. It consists of eight strands, and each strand consists of seven wires. The anchor was installed using the “single protection” technique (i.e., the steel strands without greased sheath and were backfilled directly with cement mortar). The anchor was unearthed by excavating a 1.5 m × 1.7 m tunnel. Visual inspection shows that the steel strands in the free and fixed lengths are basically stainless except for a few places where the grout failed to cover the anchor completely, thereby allowing direct contact of the strands with air. The magnitude of rebound of the tendon during the advancement of the tunnel face was simultaneously measured indicating a gradual release of bonding force, which was up to 62% of the prestressed load. This shows that the existence of the bonding force is provided by the bonding between the strand and the grout, while this bonding does not exist in the “double protection” system. The results of the mechanical test confirm that the tensile strengths in all the 33 steel wires exceed the requirement as specified by a current Chinese Standard. The concentrations of various chemicals also satisfy the requirements as specified by the China State Bureau of Quality Technical Supervision. The results of the X-ray diffraction test show that the stains taken from the surface of the strand are composed of FeO and FeOOH, both being oxide products of iron. This shows that exposure of the material to air is an important condition to initiate corrosion. By following the ASTM International G1-03 test procedure, the average corrosion rate is found to be between 3 × 10−4 and 6 × 10−4 mm/year. This investigation generally supports the use of unprotected steel strands in rock anchor.

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Performance Study of Grass-Derived Nano-Cellulose and Polycaprolactone Composites for 3D Printing

Applied Sciences ◽

10.3390/app11031273 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1273

Author(s):

Chen Feng ◽

Jiping Zhou ◽

Xiaodong Xu ◽

Yani Jiang ◽

Hongcan Shi ◽

...

Keyword(s):

3D Printing ◽

Mechanical Test ◽

Chemical Properties ◽

Test Results ◽

Performance Study ◽

Compression Process ◽

Ansys Fluent ◽

Nano Cellulose ◽

Physical And Chemical ◽

And Chemical Properties

In recent years, 3D printing has received increasing attention from researchers. This technology overcomes the limitations of traditional technologies by printing precise and personalized scaffold with arbitrary shapes, pore structures, and porosities for the applications in various tissues. The cellulose nanocrystal (CNC) is extracted from Humulus Japonicus (HJS) and mixed with poly(ε-caprolactone) (PCL) to prepare a series of CNC/PCL composites for printing. Based on the analysis of the physical and chemical properties of the series of the CNC/PCL composites, an optimal mass ratio of CNC to PCL was obtained. The Solidworks was used to simulate the stretching and compression process of the scaffolds with three different patterns under an external force. The flow of nutrient solution in the scaffolds with different patterns was simulated by ANSYS FLUENT, and then a new optimization scaffold pattern with a concave hexagon shape was advised based on the simulation results. Collectively, the mechanical test results of the material and scaffold confirmed that the optimal filling amount of the CNC was 5%, and the scaffold pattern with concave hexagon shape exhibited better mechanical properties and suitable for the transport of cells and nutrients, which is expected to be more widely used in 3D printing.

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