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Rezultatele pentru microstructureRezultate gasite: 21
Comparative corrosion study of non-precious Ni/Cr- based soft alloys in view of dental applications
Environmental Engineering and Management Journal › Vol. 7 › Nr. 1 AbstractBased on the polarization curves and electrochemical impedance spectroscopy (EIS) in the case of three commercial alloys (Wirolloy, NicromalSoft and VeraSoft) maintained in artificial saliva, it was established the type and the intensity of the corrosion process by means of the corrosion currents value. The passivation of all the samples occurred spontaneously at the open circuit potential. The corrosion currents value decrease after the alloys maintenance in the corrosive medium due the... Autori: Daniel Mareci, Gina Ungureanu, Julia Claudia Mirza Rosca, Neculai Aelenei ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25235
Nanocomposite materials based on polymers and alumina nanoparticles
Environmental Engineering and Management Journal › Vol. 8 › Nr. 4 Abstract
The synergistic combination of polymers and inorganic compounds via sol-gel process has attracted great attention, by manipulating structure at molecular level, for developing new materials with desired properties. These new hybrid materials could have a controllable combination of the benefits of polymers (flexibility, toughness, ease of processing) and those of ceramics or glasses (hardness, durability, thermal stability).
The microstructures and the properties of hybrid materials... Autori: Lucia Dumitrescu, Ileana Manciulea ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25446
Studies on titanium oxide catalyst doped with heavy metals (cadmium, copper and nickel)
Environmental Engineering and Management Journal › Vol. 8 › Nr. 4 Abstract
In order to improve the photo-efficiency of the electronic process as well as the response into the visible part of the spectrum, TiO2 doping with heavy metal (cadmium, cooper and nickel) have been employed. The objectives of this work are: (a) to prepare doped Me(Cd, Cu, Ni) TiO2 by doctor blade (DB) and spray pyrolysis deposition (SPD) techniques, (b) to characterize the catalysts, (c) to study and compare the activity of the Cd-TiO2, Cu-TiO2 and Ni-TiO2 catalysts on methyl orange ... Autori: Luminita Andronic, Bianca Hristache, Alexandru Enesca, Anca Duta, Maria Visa ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25480
Wastes used in obtaining polymer composite
Environmental Engineering and Management Journal › Vol. 8 › Nr. 5 Abstract
In the paper is analyzed the possibility of using some industrial wastes for obtaining new building materials. From the industry or from the power station a lot of by-products or wastes have resulted and their storage is a big problem for the environment. In the building material industry a part of these wastes can be used in different ways: for replacing the cement, as addition in concrete, as component of cements, in the mixture of polymer concrete, etc.
In the present investigati... Autori: Marinela Bărbuţă, Nicolae Taranu, Maria Harja ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25525
Study of morphology for geopolymer materials obtained from fly ash
Environmental Engineering and Management Journal › Vol. 8 › Nr. 5 Abstract
Geopolymerization is a continuous developing field of research for utilizing solid waste and by-products. It provides a solution to many problems where hazardous residue has to be treated and stored under critical environmental conditions. Consumption of fly ash in the manufacture of geopolymer is an important strategy in making materials more environmentally friendly. Fly ash has been chosen as a base material in order to utilize this industrial waste.
Previous researches have show... Autori: Maria Harja, Marinela Bărbuţă, Maria Gavrilescu ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25542
NUMERICAL SIMULATION OF HEAT TRANSFER IN DIRECTIONAL SOLIDIFICATION PROCESS FOR POLYCRYSTALLINE SILICON
Environmental Engineering and Management Journal › Vol. 10 › Nr. 6 Temperature distribution in the vacuum directional solidification system influenced seriously on the impurities concentration andmicrostructure in Polycrystalline Silicon. In this study, a numerical model for the transient global heat transfer for directionsolidification process has been developed by the finite element method (FEM). A two-dimension numerical simulation fortemperature distribution of directional solidification process was carried out using software Multi-physics Comsol 3.5a. Ther... Autori: Guoqiang Lv, Wenhui Ma, Hua Wang, Xiangyang Mei, Kuixian Weihttp://www.ecozone.ro/reviste.php?RID=25671
IMPROVING SOIL QUALITY BY ADDING MODIFIED ASH
Environmental Engineering and Management Journal › Vol. 11 › Nr. 2 Fly ash and fly ash based zeolites are inorganics used for improving soil quality. In the current paper, the hydrothermal modification of fly ash was studied. Three methods have been employed for this purpose. The first method involved the use of an autoclave, where synthesis has been performed at a temperature of 120 0C and a treatment time of 4 to 8 hours. Within the second method, the modification of the ash at a temperature of 600 0C by fusion was carried-out. In this method, a mixture of as... Autori: Corneliu Munteanu, Daniel Bucur, Lacramioara Rusu, Maria Harja, Marinela Barbuta, Ramona Carla Ciocinta ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=25885
EFFECTS OF ACIDIC AND ALKALINE POLLUTANTS ON THERMAL BEHAVIOUR, MICROSTRUCTURE AND MECHANICAL PROPERTIES OF CLAYS
Environmental Engineering and Management Journal › Vol. 12 › Nr.10 AbstractThermal behaviour, microstructure and mechanical properties of the clay polluted by acidic and alkaline pollutants wereinvestigated by thermogravimetric/differential thermal analysis (TG-DTA), scanning electronic microscope (SEM), mercuryintrusion experiments, permeability coefficient and unconfined compressive strength tests. The clay polluted by alkaline solutionpresented distinct exothermic peaks at 304-310oC, while it’s not observed for the one polluted by acidic solution due to thed... Autori: Zhao Ying ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26182
INVESTIGATION OF THE EFFECT OF MOISTURE IN THE TIME LAG OF BUILDING WALLS WITH DIFFERENT INSULATING MATERIALS
Environmental Engineering and Management Journal › Vol. 13 › Nr. 11 AbstractThe thermal and water insulation of buildings is extremely important. Currently, the most applied insulation materials in thebuilding sector are plastic foams and fibrous materials. Different types of polystyrene materials are used as water and thermalinsulators, e.g., expanded polystyrene (EPS) and extruded polystyrene (XPS). The differences between the different polystyrenematerials is found in their manufacturing processes and thus in their microstructure. Our research focuses on the ... Autori: Ákos Lakatos ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26546
ELUCIDATING CHARACTERISTICS OF GEOPOLYMER WITH SOLAR PANEL WASTE GLASS
Environmental Engineering and Management Journal › Vol. 14 › Nr. 1 Abstract
This study examined the characteristics of geopolymer with solar panel waste glass. After 28 days of curing, the compressive
strengths of the geopolymer samples containing 10 mass % and 20 mass % solar panel waste glass were 63.3± 1.8 and 49.1 ± 2.2
MPa, respectively. The geopolymer sample with 10% solar panel waste glass exhibited a stronger reaction than that with 20%
solar panel waste glass, and the strength decreased as the amount of solar panel waste glass increas... Autori: HuiCong Hao ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26621
THERMAL CONDUCTIVITY INVESTIGATION OF COMPOSITE FROM HEMP AND PEAT FIBRES
Environmental Engineering and Management Journal › Vol. 14 › Nr. 9 Abstract
A large number of energy inefficient buildings were constructed without taking into account the principles of green building,
which requires efficient utilization of local resources. In this work hemp and peat fibres were used in order to produce effective
ecological thermal insulating material. Tests were carried out using short dishevelled hemp and chopped peat fibres. Effective
composites from local renewable resources were produced. Macro- and microstructures of composites as we... Autori: Rūta Stapulionienė ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=26844
PREPARATION AND SEM-EDX-XRD CHARACTERIZATION OF MAGNETIC ZEOLITIC MATERIALS OBTAINED FROM COAL FLY ASH
Environmental Engineering and Management Journal › Vol. 16 › Nr. 11 A low-cost magnetic zeolitic material was synthesized from coal fly ash by means of a new, simple method involving alkaline
hydrothermal zeolitization of fly ash (FA) followed by low-intensity wet magnetic separation. Scanning electron microscopy
with energy-dispersive X-ray analysis was applied to characterize the composition, microstructure, and morphology of the
material. The mineral and synthetic zeolite phases were identified by powder X-ray diffraction. The obtained magnetic zeolitic
m... Autori: Annie Shoumkova ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27486
ELUCIDATING THE EFFECTS OF NANOSILICA ON THE CHARACTERISTICS OF ALKALI-ACTIVATED THIN-FILM TRANSISTOR LIQUID-CRYSTAL DISPLAY WASTE GLASS
Environmental Engineering and Management Journal › Vol. 17 › Nr. 2 Thin-film transistor liquid-crystal display (TFT-LCD) waste glass can be used as a raw material for producing geopolymers, because it contains large amounts of silicon and aluminum in its amorphous structure. The setting time and compressive strength were evaluated to determine the quality of the geopolymer product with various amounts of nano-SiO2 (0%–3%) and TFT-LCD waste glass replacement (0% - 40%). The microstructures of the samples were characterized using mercury intrusion porosimet... Autori: Kang Gao ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27634
VARIETY BEHAVIORS OF DEPTH AND SURFACE FILTER MEDIA WITH THE AGES FOR PLEATED FILTER CARTRIDGES
Environmental Engineering and Management Journal › Vol. 17 › Nr. 11 The aim of this study is to investigate a variety behaviors of two kinds of media (multiple-layer structures and multiple-layer structures combined with surface treatment, such as finer fibers) with ages using a scanning electron microscope (SEM) and to determine the effect of fabric microstructures on cake formation and pulse cleaning. The results show that fine particles are readily deposited on the surface and inside depth filter medium. The fine fibers with diameters (~0.08 microns, this val... Autori: Yan Cuiping ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27842
CACTUS JUICE PREPARATIONS AS BIOFLOCCULANT: PROPERTIES, CHARACTERISTICS AND APPLICATION
Environmental Engineering and Management Journal › Vol. 18 › Nr. 1 In this study, the flocculating properties of different cactus juice preparations were assessed using synthetic and real industrial and
leachate wastewaters. It was found that the crude CJ had a flocculating activity (FA) of 89 ± 2.2% which is significantly higher
than that of a powdery sample derived from a 60°C oven-dried CJ sample and which was about 37.8 ± 2.5%. Interestingly, both
crude and dried samples showed the ability to flocculate kaolin suspensions within a wide ... Autori: Moncef Khadhraoui ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=27887
STUDY ON SOLID/LIQUID RATIO AND MICROSTRUCTURE PROPERTIES OF ALKALI-ACTIVATED METAKAOLIN-BASED GEOPOLYMER CONTAINED IN LCD WASTE GLASS
Environmental Engineering and Management Journal › Vol. 19 › Nr. 1 There are considerable environmental and health and safety concerns regarding liquid crystal display (LCD) waste glass because of the waste electrical and electronic equipment (e-waste) that is deposited in landfills. In current study, the effect of variation in LCD waste glass on the deconvoluted fractions of silicon centers of metakaolin geopolymers has been comprehensively investigated to discover the underlying mechanisms governing the performance. Solid/liquid ratio affects the kinetics of ... Autori: Kang-Wei Lo ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28146
PREPARATION OF NEW INORGANIC POLYMER FLOCCULANT AND ITS APPLICATION IN OILY SLUDGE
Environmental Engineering and Management Journal › Vol. 19 › Nr. 3 Sodium silicate, iron sulfate, magnesium sulfate, and zinc sulfate were used as the raw materials to prepare a new inorganic polymer flocculant, polysilicate ferric magnesium zinc (PSFMZ), using direct recombination. The effects of molar ratio of zinc to silicon, ratio of iron to magnesium, reaction temperature, and reaction time on deoiling rate were explored. The optimal synthesis conditions for the flocculant for the thermal-washing treatment of oily sludge were determined. Results showed tha... Autori: Lanlan Yu ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28165
MICROSTRUCTURAL AND PHYSICAL CHARACTERIZATION OF SOLID WASTES FROM CLAY BRICKS FOR REUSE WITH CEMENT
Environmental Engineering and Management Journal › Vol. 19 › Nr. 4 This study aims to evaluate the properties of different wastes obtained from four red ceramic brick industries in the northern region
of Santa Catarina, Brazil. The characterization of the clay brick waste (CBW) was performed using the XRD techniques, XRF,
FTIR, DTA and SEM. Techniques to determine the pozzolanic activity, particle size, B.E.T. surface area and specific mass were
used. The consumption of calcium hydroxide (CH) in the cementitious pastes with the CBWs was also measured. An app... Autori: Adilson Schackow ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28184
CLAY COMPOSITE WATER FILTERS: THE CASE OF FLUORIDE, NITRITE AND Escherichia coli REMOVAL
Environmental Engineering and Management Journal › Vol. 19 › Nr. 4 Inorganic ceramic materials is receiving more attention in recent times due to their unique characteristics which include
different pore structures, hydrophilic surfaces, high chemical, thermal and mechanical stabilities that offer avenues for application
in water treatment. In the present work, cost-effective clay ceramic water filters of different designs were developed from clay (50,
60, and 70) %, sawdust (15, 20, 25, and 35) %, grog (5, 10 and 15)% ratios plus 5% bone char by volume and ... Autori: Enyew Amare Zereffa ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28196
RECYCLING OF LIGHT-EMITTING DIODE WASTE QUARTZ SAND ACTING AS A POZZOLANIC MATERIAL FOR PORTLAND CEMENT
Environmental Engineering and Management Journal › Vol. 19 › Nr. 5 LED waste quartz sand (LEDWS), which is a prominent by product of the LED manufacturing process, may contaminate the environment because it comprises specific heavy metals (e.g., As and Cu), which are hazardous ingredients to the environment when disposed of improperly. Therefore, this study investigated the use of light-emitting diode (LED) waste quartz sand to partially replace Portland Type I cement (OPC) to evaluate the feasibility of reusing it as a pozzolanic material. The SiO2, Na2O, and ... Autori: Kae-Long Lin ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28207
USE OF TANNERY SLUDGE IN CLAY BRICK MANUFACTURING
Environmental Engineering and Management Journal › Vol. 19 › Nr. 5 The paper analyses the possibilities of recycling tannery sludge (TS) in clay brick manufacture. The physico-mechanical properties and microstructure of clay brick and cement mortars vary depending on TS content in the mix. 2.5 %–15.0  TS (by weight) was added to clay bricks fired at 1000 ï‚°C temperature and maintained at maximum heat for 1 hour. The tests revealed that 2.5  TS
addition had a positive effect on physical and mechanical properties of clay brick: reduce drying and mfi... Autori: Olga Kizinievič ISSN: 1843 - 3707 http://www.ecozone.ro/reviste.php?RID=28209 |