Influence of Micro-Milled Secondary Materials Used as Binders in Low Level Stabilized Cold Recycled Asphalt Mixtures

2017 ◽  
Vol 731 ◽  
pp. 29-36 ◽  
Author(s):  
Jan Suda ◽  
Jan Valentin
Keyword(s):  
High Speed ◽  
Economic Value ◽  
Average Particle Size ◽  
Environmental Benefits ◽  
Average Particle ◽  
Recycled Asphalt ◽  
Low Level ◽  
Foamed Bitumen ◽  
Materials Used ◽  
By Products

This paper presents an experimental verification of the alternative options for using by-products or mineral waste materials applied to cold recycled mixtures with low level of stabilisation intended for low-volume road structures. To achieve the necessary refinement and a certain level of reactivity potential, the by-products were activated mechanically, i.e. pulverized in a high-speed disintegrator with respect to the lowest possible energy demands of the process and to the level of wear-and-tear of the working components in the milling machine. Such refined material, with average particle size of 10-15 μm, is applies as an active filler component allowing to partly substitute hydraulic binder in cold recycled mixtures. The application of such materials in structural pavement layers should increase the environmental benefits and result in added economic value. The experimental measurements taken focused on cold recycled mixtures with low level of stabilisation, modified by a combination of binders, or namely cement, mechanically activated concrete from reclaimed concrete pavement slabs originating from the Czech backbone D1 highway modernisation, mechanical-chemically activated fluid ashes from the Pilsen heat plant and foamed bitumen. Both basic volumetric properties and strength and deformation parameters were set for the purposes of evaluation of the characteristic measured in the experimental mixes.

scholarly journals Alternative Micro-Milled Binders in Cold Recycling Technologies

2019 ◽  
Vol 27 (2) ◽  
pp. 16-20
Author(s):  
Jakub Šedina ◽  
Jan Valentin ◽  
Petr Mondschein ◽  
Jan Suda
Keyword(s):  
High Speed ◽  
Chemical Activation ◽  
Milling Process ◽  
Reactive Material ◽  
Indirect Tensile ◽  
Foamed Bitumen ◽  
Cold Recycling ◽  
Water Susceptibility ◽  
By Products ◽  
Structural Layer

AbstractIn addition to bituminous binders (bituminous emulsion, foamed bitumen), hydraulic binders are applied in cold recycling technologies to increase the strength of a final structural layer as well as to increase its resistance to water and frost impacts. This paper deals with the use of energy by-products from fluidized bed coal combustion and mineral waste and their modification into reactive material with the potential of replacing commonly used hydraulic binders. The increase in the reactive potential takes place through a high-speed milling process where the mechanical-chemical activation of the material takes place. This process is associated with the refinement of the material, a higher proportion of micro and nanoparticles, an increased surface area, opening of particles, etc. The material treated exhibits binding properties, and it can be used as an active filler that allows for the partial or complete substitution of hydraulic binders. The experimental part is focused on the application of alternative binders to cold recycling mixtures and their assessment according to valid technical regulations, i.e., an assessment of their indirect tensile strength and water susceptibility as well as compressive strength and resistance to the effects of water and frost.

Preparation and characterization of natural quercetin-based Mongolia Medicine SenDeng-4 nanoemulsion (N-QUE-NE) and its antibacterial activity..

2020 ◽  
Vol 18 ◽  
Author(s):  
Yanfang Zhang ◽  
Rina Du ◽  
Pengwei Zhao ◽  
Sha Lu ◽  
Rina Wu ◽  
...  
Keyword(s):  
Particle Size ◽  
Antibacterial Activity ◽  
Zeta Potential ◽  
High Speed ◽  
Antibacterial Effect ◽  
Average Particle Size ◽  
Antagonistic Effect ◽  
Dilution Method ◽  
Average Particle

Background: Quercetin is the main active ingredient of Xanthoceras sorbifolia Bunge. Traditional compatibility theory of traditional Chinese medicine has typically reported a synergistic interaction among multiple components, while the synergistic effects of nanoemulsion have not been fully clarified. Objective: To study preparation and characterization of quercetin-based Mongolia Medicine Sendeng-4 nanoemulsion (NQUE-NE) and its antibacterial activity and mechanisms. Methods: The morphology of the nanoemulsion was observed by transmission electron microscopy (TEM), and the zeta potential, polydispersity index (PDI), and particle size distribution were determined by the nanometer particle size analyze. The stability of nanoemulsion was investigated by light test, high speed centrifugal test and storage experiment at different temperature. The combined bacteriostatic effect of N-QUE-NE was studied in vitro by double-dilution method and checkerboard dilution method. Results: The appearance of N-QUE-NE was pale yellow, clear and transparent. The nanoemulsion particles were spherical and uniformly distributed under TEM. The PDI was 0.052, the average particle size was 19.6nm, and the Zeta potential was -0.2mV. When quercetin nanoemulsion (QUE-NE) was used in combination with tannin nanoemulsion (TAN-NE) and toosendanin nanoemulsion (TOO-NE), it exhibited a synergistic antibacterial effect. However, the combination of QUE-NE and geniposide nanoemulsion (GEN-NE) exhibited an antagonistic effect. It was revealed that the antibacterial effect was in order of quercetin-tannin-toosendanin nanoemulsion (QUE-TAN-TOO-NE) ＞ quercetin-tannin nanoemulsion (QUE-TANNE) ＞ QUE-NE ＞ quercetin-tannin-toosendanin-geniposide nanoemulsion (QUE-TAN-TOO-GEN-NE). Conclusion: This study explored the preparation and efficacy of N-QUE-NE, and the results showed that quercetin, tannin and toosendanin had satisfactory synergistic antibacterial effects. The antagonistic effect of quercetin and geniposide in nanoemulsion indicated that it is not beneficial to the antibacterial effect of Sendeng-4, and further research needs to be conducted to clarify its antibacterial effect.

Synthesis and Characterization of Graphene/Zinc Oxide Nanocomposites

2017 ◽  
Author(s):  
Nurettin Sezer ◽  
Adnan Ali ◽  
Muataz A. Atieh ◽  
Muammer Koc
Keyword(s):  
Zinc Oxide ◽  
Average Particle Size ◽  
Zinc Nitrate ◽  
Synthesis And Characterization ◽  
Average Particle ◽  
Nitrate Hexahydrate ◽  
Gravimetric Analysis ◽  
Impregnation Method ◽  
Materials Used

This study investigates the synthesis and characterization of graphene/zinc oxide nanocomposites. Wet impregnation method was employed for the synthesis. Firstly, graphene nanoplatelets and zinc nitrate hexahydrate were concurrently dispersed in ethanol and subjected to sonication for 1 h. Then, the dispersion was put in a furnace at 70 °C overnight. The paste was then collected and heated further up to 400 °C in air for a duration of 4 h. The process was proceeded to yield insoluble nanocomposites. The synthesis was followed by characterization of the nanocomposite samples by Field Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction (XRD) and Thermal Gravimetric Analysis (TGA). The XRD pattern revealed the presence of ZnO crystals and graphene. The FESEM images showed that ZnO crystals with average particle size of 30 nm are uniformly distributed on graphene surfaces. According to the TGA result, the content of nanocomposites is in good agreement with the materials used during synthesis.

Formulation of Polymeric Nanoparticles of Lercanidipine by Two Bottom Down Techniques Optimized by Design of Experiment

2020 ◽  
Vol 57 (3) ◽  
pp. 1-18
Author(s):  
Alicia Menezes ◽  
Shanthi Lysetty ◽  
Anup Naha
Keyword(s):  
High Speed ◽  
Polymeric Nanoparticles ◽  
Average Particle Size ◽  
Tween 80 ◽  
Oral Route ◽  
Average Particle ◽  
Channel Blockers ◽  
Factorial Method ◽  
Major Disadvantage ◽  
Preformulation Studies

Lercanidipine has found to be effective in lowering blood pressure among the potent calcium channel blockers, through its action on L- type calcium channels. However, the major disadvantage associated with Lercanidipine is, it is a BCS class II drug having low solubility bioavailability is around 10% through oral route due of extensive first pass metabolism. The present study is aimed to prepare and evaluate polymeric nanoparticles of Lercanidipine using a combination of two bottom down techniques, High speed homogenizer and Probe sonication. Preformulation studies like, DSC, FTIR using surfactants such as Tween 80, Sodium Lauryl sulphate, Polyvinyl Alcohol, singely and in combination were used. A full factorial method was utilized to study the effect of various factors such as surfactant concentration, homogenization speed, sonication amplitude and sonication time on Lercanidipine nanoparticles in two levels. Optimized nanoparticles (with PVA as surfactant) showed an average particle size of 141 nm, PDI 0.248 and zeta potential +6.46. Formulation was further optimized using Design Expert 10 software. Optimized formulation was found to be stable during 3 months stability studies as per ICH guidelines.

Nucleate Boiling Heat Transfer on Plain and Microporous Surfaces in Subcooled Water

2017 ◽  
Vol 139 (8) ◽  
Author(s):  
Seongchul Juna ◽  
Jinsub Kima ◽  
Hwan Yeol Kimb ◽  
Seung M. Youa
Keyword(s):  
Heat Transfer ◽  
High Speed ◽  
Average Particle Size ◽  
Nucleate Boiling ◽  
Average Particle ◽  
Transfer Coefficients ◽  
Sem Image ◽  
Subcooled Water ◽  
Plain Surface ◽  
Bubble Sizes

The growth of hovering bubbles on Copper, High-Temperature Thermally-Conductive Microporous Coating (Cu-HTCMC) and plain surface were compared at 1,000 kW/m2 in nucleate boiling with different subcoolings. Images obtained by a high speed camera operating at 2,000 frames per second were used. The Cu-HTCMC was created by sintering copper powders with the average particle size of 67 μm and ∼300 μm thickness, which showed the optimized nucleate boiling and critical heat flux enhancement. The hovering bubble size became smaller as subcooling increased for both Cu-HTCMC and plain surface due to condensation by surrounding subcooled water. At 30 K subcooling, big hovering bubbles disappeared on both surfaces. Small bubbles were shown on plain surface and mists were shown on Cu-HTCMC surface. The hovering bubble sizes were close and the growth times were comparable for both surfaces in saturated and 10 K subcooling cases. However, the bubbles on Cu-HTCMC surface were smaller than those of plain surface at 20 K and 30 K subcoolings. This is believed to be due to the microporous structures shown in the SEM image (top left figure). The heat transfer coefficients of Cu-HTCMC were ∼300 kW/m2K for various subcoolings, about 6 times higher than those of plain surface (top right figure). The figure indicates slightly increasing trend of the heat transfer coefficient with subcooling. This is believed to be the result of the disappearance of relatively big size bubbles in Cu-HTCMC case.

Corrosion Properties of Magnetron Sputtered Al-Mg Alloy Coatings on High-Speed Electro-Galvanizing Steel

2009 ◽  
Vol 79-82 ◽  
pp. 1987-1990
Author(s):  
Xun Lei Gu ◽  
Yu Qiao Shan ◽  
Chang Sheng Liu
Keyword(s):  
Corrosion Resistance ◽  
Substrate Temperature ◽  
High Speed ◽  
Average Particle Size ◽  
Electrochemical Measurement ◽  
Corrosion Current ◽  
Average Particle ◽  
Corrosion Properties ◽  
Corrosion Resistance Property ◽  
Target Power

The Al-Mg coatings were deposited on high-speed electro-galvanizing steel by using double-target DC magnetron sputtering. Numerous Al-Mg coatings were prepared with a range of different Mg-target power at different substrate temperatures. The morphologies and compositions were analyzed by SEM, EDS and XRD, the corrosion-resistance properties with different sputtering parameters were discussed by electrochemical measurement. It was found that with the substrate temperature increasing, the porosity decreased, meanwhile, higher substrate temperature resulted in more granular particles and an increased average particle size, but that did not affect corrosion properties obviously. The corrosion-resistance properties were found to be significantly affected by the targets power. As the power of Al-target and Mg-target were 900W and 200W respectively, the film acted the best corrosion-resistance property. Corrosion current density was approximately 4μA/cm2, decreased significantly compared with galvanized sheet. After analysis, the coating was mainly composed of Al12Mg17 which afforded sacrificial anode protection. As the Mg-target power over high relative to Al-target, the coating was composed of Al12Mg17 and MgZn2, the latter can cause micro-galvanic acceleration of corrosion.

Green Chemistry Preparation of thiochromeno[4,3-b]pyran and benzo[h]thiazolo[2,3-b]quinazoline Derivatives using HSBM Technique over ZnAl2O4 Nano-Powders

2019 ◽  
Vol 22 (6) ◽  
pp. 421-427
Author(s):  
Seyyed Jalal Roudbaraki ◽  
Sadaf Janghorban ◽  
Majid Ghashang
Keyword(s):  
High Speed ◽  
Average Particle Size ◽  
Reaction Times ◽  
Environmentally Friendly ◽  
Average Crystallite Size ◽  
Precipitation Method ◽  
Average Particle ◽  
Efficient Catalyst ◽  
Quinazoline Derivatives ◽  
Co Precipitation

Aim and Objective: The aim of this paper is to introduce HSBM as a green and environmentally friendly technique for the synthesis of thiochromeno[4,3-b]pyran and benzo[h]thiazolo[2,3-b]quinazoline derivatives over ZnAl2O4 nanopowders as an efficient catalyst. Materials and Methods: ZnAl2O4 nanopowders were synthesized via a co-precipitation of Zn(NO3)2 and Al(NO3)3 salts and were characterized by XRD, FE-SEM, TEM and DLS techniques. The as-prepared ZnAl2O4 nano-powders have been used as a catalyst on the synthesis of pyran nucleus using high-speed ball milling (HSBM) technique. The structure of products was confirmed with NMR analysis. Results: ZnAl2O4 exhibits a cubic crystal structure (Space group: Fd-3m) with the average crystallite size of 41 nm. The average particle size of ZnAl2O4 nano-powders determined by DLS technique is 55 nm. The catalytic activity of nano-powders was examined on the synthesis of 2- amino-4,5-dihydro-4-arylthiochromeno[4,3-b]pyran-3-carbonitriles, (8Z)-2-amino-8-arylidene-4,5, 7,8-tetrahydro-4-arylthiopyrano[4,3-b]pyran-3-carbonitriles, 4-aryl-3,4,5,6-tetrahydrobenzo[h]quinazoline- 2(1H)-thiones and 4-aryl-1,3,4,5-tetrahydro-2H-thiochromeno[4,3-d]pyrimidine-2-thione derivatives. All products were obtained in high yields with short reaction times. Conclusion: ZnAl2O4 nanopowders were prepared via a cost-effective co-precipitation method and showed good potential for the synthesis of 4H-pyran analogous in good yields. The salient advantages of HSBM technique include environmentally friendly with reduced solvents, is a simple technique and has low energy costs.

scholarly journals Synthesis and Characterization of CeO2/CuO Nanocomposites for Photocatalytic Degradation of Methylene Blue in Visible Light

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 305
Author(s):  
Alia Raees ◽  
Muhammad Asghar Jamal ◽  
Ikram Ahmed ◽  
Mika Silanpaa ◽  
Tahani Saad Algarni
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Organic Pollutant ◽  
Average Particle Size ◽  
Environmental Benefits ◽  
Precipitation Method ◽  
Polluted Water ◽  
Average Particle ◽  
Industrial Wastewaters ◽  
Vis Spectroscopy

Removal of hazardous organic dyes from polluted water bodies requires the introduction of strong adsorbents and photocatalysts to industrial wastewaters. Herein, photocatalytic CeO2 nanoparticles and CeO2/CuO nanocomposite were synthesized following a co-precipitation method for low cost elution of methylene blue (MB) from water. The crystallinity and surface structure of the as-prepared materials have been analyzed using characterization techniques including X-ray powder diffraction (XRPD), field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), ultra-violet visible spectroscopy (UV–Vis), and Fourier-transform infrared spectroscopy (FTIR). The average particle size of both the nano scaled samples were approximately 20–30 nm. The photocatalytic properties of CeO2/CuO were investigated under visible light against methylene blue (MB). The results showed 91% photodegradation of MB organic pollutant in 3 h as monitored by UV–Vis spectroscopy. Absorbance peaks appeared at around 670 nm corresponding to degradation of MB. Such output displayed the effectiveness of Ce nanocomposites for environmental benefits. Hence, CeO2/CuO nanocomposite could be useful for treatment of industrial wastewaters by removing hazardous MB dye.

Erosive Wear Study of HVOF Spray Cr3C2–NiCr Coated CA6NM Turbine Steel

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Deepak Kumar Goyal ◽  
Harpreet Singh ◽  
Harmesh Kumar ◽  
Varinder Sahni
Keyword(s):  
High Speed ◽  
Protective Coatings ◽  
Average Particle Size ◽  
Erosive Wear ◽  
Average Particle ◽  
Slurry Erosion ◽  
Spray Process ◽  
Hvof Spray ◽  
Turbine Steel ◽  
Ca6nm Steel

Degradation of surfaces of hydroturbine components caused by impact of abrasive particles carried by flowing water is a serious issue. To counteract the same, surface modification of turbine materials by the application of protective coatings is gaining popularity these days. In this work, Cr3C2–NiCr coating was deposited on CA6NM turbine steel by the HVOF spray process and studied with regard to its performance under different slurry erosion conditions. The effect of three parameters, namely average particle size of slurry particles, speed (rpm), and slurry concentration on slurry erosion of this coating material, was studied by using a high speed erosion test rig. The analysis of the surfaces of the samples before and after slurry erosion tests was done by using SEM. The HVOF sprayed Cr3C2–NiCr coating showed very good performance under slurry erosion in comparison with uncoated CA6NM steel.

Technical and Economic Impacts of Pre-Shredding the MSW Feed to Moving Grate WTE Boilers

2009 ◽  
Author(s):  
Garrett C. Fitzgerald ◽  
Nickolas J. Themelis
Keyword(s):  
High Speed ◽  
Average Particle Size ◽  
Waste To Energy ◽  
Average Particle ◽  
Heat Transfer Theory ◽  
Final Design ◽  
Waste Transfer ◽  
Transfer Stations ◽  
New Generation ◽  
Chemical Rate

Chemical rate and heat transfer theory indicates that the combustion performance and productivity of a moving grate waste-to-energy boiler should be enhanced by means of pre-shredding of the MSW, thus reducing the average particle size, homogenizing the feed, and increasing its bulk density by an estimated 30%. However, the capital, operating and maintenance costs of the shredding equipment should be low enough so that existing or new WTE facilities consider pre-shredding of the MSW. In cases where MSW is transported to a central WTE from a number of Waste Transfer Stations (WTS), pre-shredding may take place at the WTS, thus increasing density and decreasing transportation costs. This is a mechanical engineering study that examined the evolution and present state of shredding equipment since 1994 when the last WTE shredder in the U.S. was installed at the SEMASS facility. The quantitative benefits realized through the pre-processing of MSW by means of modern shredding equipment are evaluated both for the traditional high speed hammermills and the new generation of low-rpm, high-torque shredders. The combustion characteristics of shredded MSW were analyzed and compared to those of the “as-received” material that is presently combusted in mass burn WTEs. The emphasis of the project has been on equipment that can be integrated in the traditional flowsheet of a WTE and serviced readily. The most important criterion in the final design will be that the economic and energy benefits of pre-shredding be clearly greater than the conventional operation of combusting as received MSW.

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