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Kaolinite is able to assure the high binding affinity of the filler particles of raw ceramic bodies. It acts as a matrix that strongly holds the other constituents' particles in a compact structure. The slurry samples were characterized by XRD, mineralogical microscopy and SEM coupled with an EDX elemental analysis. The slurry collected from the ceramic tile production wastewaters had a significant amount of kaolinite (36%), mostly fine particles of 3 µm, less surrounding quartz (37%) and mullite (19%) particles of 5–100 µm in diameter and traces of lepidocrocite (8%). It is a dense paste with a relative moisture of 25%. The square bar of the slurry as received, pressed at a load of 350 N, had a flexural strength of 0.61 MPa. Increasing the moisture to 33% using regular water, followed by mechanical attrition at 2000 rpm for 5 min, resulted in a porous bar with a flexural strength of 0.09 MPa; by increasing the attrition speed to 6000 rpm, the microstructural homogenization was improved and the flexural strength was about 0.68 MPa. It seems that regular water does not assure an optimal moisture for the kaolinite matrix conditioning. Therefore, we used technological water at pH = 10, a moisture of 33% and attrition at 6000 rpm for 5 min, and the bar pressed at a load of 350 N had a flexural strength of 1.17 MPa. The results demonstrate that the bar moistened with technological water and an attrition regime assured a proper conditioning for the kaolinite matrix, achieving the optimal binding of the quartz and mullite particles under the pressing load. Bars with the optimal mixture were pressed at several loads, including 70, 140, 210 and 350 N, and the flexural strength was progressively increased from 0.56 MPa to 1.17 MPa. SEM fractography coupled with atomic force microscopy (AFM) revealed that the optimal moisture facilitated a proper kaolinite particle disposal regarding the quartz and mullite filler particles, and the progressive load assured the strong binding of the finest kaolinite platelets onto their surface. [ABSTRACT FROM AUTHOR]

Ceramic slurry wastes have a significant hazardous potential when dumped. Their recycling as raw material is a sustainable approach for the development of nature-friendly applications. The microstructure and mechanical properties play a key role in the success of this sustainable recycling. Ceramic slurry samples resulting from the wall and floor tiles production facility were analyzed. The mineral composition was investigated by XRD combined with mineralogical microscopy and the microstructure was investigated by SEM microscopy coupled with EDX spectroscopy and elemental mapping. The ceramic slurry contains: quartz, kaolinite, mullite and small amounts of lepidocrocite. Quartz and mullite particles have sizes in the range of 5–100 μm and kaolinite has small particles of around 1 to 30 μm. Iron hydroxide crystallized as lepidocrocite is finely distributed among kaolinite aggregates. It makes the slurry unable to be reused in the technological process because of the glaze staining risk, but it does not affect the material cohesion. Thus, the cylindrical samples were prepared at progressive compactions rates as follows: 1808.55; 1853.46; 1930.79 and 2181.24 kg/m3 and dried. Thereafter, were subjected to a compression test with a lower compression strength of 0.75 MPa for lower density and a higher strength of 1.36 MPa for the higher density. Thus, slurry compaction enhances the kaolinite binding ability. The Young's Modulus slightly decreases with the compaction increasing due to local microstructure rigidizing. This proves the binding ability of kaolinite, which properly embeds quartz and mullite particles into a coherent and resistant structure. The fractography analysis reveals that fracture starts on the internal pores at low compaction rates and throughout the kaolinite layer in the samples with high compactness. The observed properties indicate that the investigated ceramic slurry is proper as a clay-based binder for sustainable ecological buildings, avoiding the exploitation of new clay quarries. Also, it might be utilized for ecological brick production. [ABSTRACT FROM AUTHOR]

Ferrous particles are usually found in atmospheric particulate matters due to the cars chassis oxidation. These particles are able forming conglomerates with the other mineral particles. Thus, the investigated carwash slurry (CS) reveals a high mineralized composition dominated by Quartz, Calcite and clay minerals with significant amount of iron hydroxides. We found some unusual bigger particles of ferrous conglomerate (FC) into the CS sample. XRD and mineralogical microscopy (MOM) reveal that FC sample is formed by a nanostructured mixture of 56 wt.% Calcite and 44 wt.% Goethite. SEM images and EDS spectra reveal submicron particles within the FC structure with a dense mixture of Ca and Fe. FTIR investigation reveal strong absorption bands for goethite and very weak ones for Lepidocrocite within the FC sample. The results indicates that the conglomerate weas formed on the car chassis rust by wet partial dissolution of calcite that locally forms Ca(OH)2 which further is re-crystallized as calcite due to the CO2 from the combustion gases. Fine crystallites of iron hydroxides are embedded into the re-crystallized calcite. In conclusion, the magnetic selection is recommended for the ferrous conglomerate particles removal from CS to be used as natural coverage for of urban dump sites rehabilitation. [ABSTRACT FROM AUTHOR]

Prima descriere a mieroporticulelor datează din 1967, când Wolf a comunicat prezenţa fragmentelor membranare trombocitare în plasma umană, numindu-le “praf placlietar”. Aceste vezicule au fost ulterior denumite microparticule, iar cunoştinţele despre caracterizarea şi funcţia lor au avansat de atunci. Generarea de microparticule reprezintă un mecanism de comunicare intercelulară, având diferite roluri, atât în statusul fiziologic, cât şi în diverse afecţiuni. în afară de participarea lor în patogenia unor procese precum inflamaţia, aterogeneza sau metastazarea neoplaziilor, microparticulele trombocitare sunt implicate în trombogeneză. Factorul tisular şi fosfatidilserina sunt ambele expuse pe membrana externă a microparticulelor trombocitare, oferind suprafeţe catalitice procoagulante. Evaluarea microparticulelor constituie un potenţial instrument de investigare şi diagnostic. Enumerarea şi caracterizarea lor reprezintă o provocare, iar metoda de analiză cea mai utilizată este citometria în flux. Având în vedere tendinţa actuală de a considera microparticulele ca fiind un adevărat rnarker de diagnostic, autorii îşi propun să prezinte o imagine de ansamblu asupra celor mai relevante informaţii cu privire la proprietăţile principale, mecanismele de producţie şi importanţa clinică a microparticulelor trombocitare

It was carried out the monitoring of the qualitative parameters for the "Ocnei" and "Rotund" lakes located in the protected area "Salina Turda", Romania, and as well it was made a comparative analysis of the results with previous determinations. It was determined the evolution of the physico-chemical parameters on 5 segments of depth. The monitoring was carried out within 2 measurement campaigns. It has been determined that the lakes tend to lose basicity and it was found that the heliotherm phenomenon represents a stable index in comparison with previous determinations. [ABSTRACT FROM AUTHOR]

The research described in this paper performs a centralization of the dates for the open lakes for recreation and treatment, after 7 years from opening. In the context of the work, it has been achieved environmental analyses for „Ocnei" and „Rotund" lakes, located in the Salina Turda area. It has pursued the evolution of the quality parameters on depth of the lakes, intended for the tourist activity as well spa. The monitoring process was achieved through the deployment of one measurement campaign developed in April 2016. From this research results that the lakes have a tendency to lose basicity and the temperature increases with the increasing of the depth, which determines the presence of heliotherm phenomenon. [ABSTRACT FROM AUTHOR]

In this paper are presented preliminary studies regarding the utilization of microorganisms for the decontamination of soils polluted with heavy metals. The concentration of heavy metals was determined by inductive coupled plasma atomic emission spectroscopy (ICP-AES). It has been confirmed that the studied area is polluted with Zn, Pb, Cr, Fe, Cu, Cd, Mn, the concentrations exceeding in most cases the alert threshold and the intervention threshold. The experiments led to the conclusion that this area needs reclaiming which can be done by bioleaching. This is a biologic treatment method, which uses microorganisms to encourage the solubility and the extraction of heavy metals from polluted soils. [ABSTRACT FROM AUTHOR]

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The mining industry represented for numerous consecutive centuries an important branch of the Romanian economy. The specific activity of exploration and exploitation of mineral resources and ore processing in plants in order to obtain metals induced a further environmental pollution. The purpose of this paper is to identify pollutants in the mining perimeter Larga de Sus, Zlatna (Alba County) to determine the impact on environmental factors through geomorphological alteration of soil and continual pollution of surface waters. [ABSTRACT FROM AUTHOR]

This paper analyzes the quality index of baking values regarding some domestic and foreign varieties of wheat, grown in a comparative crop from two counties of Romania Satu Mare and Bihor. The agriculture in the western area and overall in Romania, doesn't have the characteristics of sustainable agriculture, since the obtained production is far from the performance criteria of European agriculture, poor management of risk factors is one of the causes of this situation. The research objectives were: • the establishing the productive potential of varieties of winter wheat • the unlocking the potential of productive varieties of wheat; • the correlation of productive characteristics regarding varieties of bread wheat quality [ABSTRACT FROM AUTHOR]

Activated Protein C resistance (APCR) is the most frequency trombophilia that induces thrombotic complications of pregnancy that itself is a hypercoagulable state. Abnormal placental vasculature is the most important mechanism that causes various complications. The screening diagnosis of APCR is influenced by physiological changes of hemostasis in pregnancy and may be difficult. We propose to evaluate the risk for thrombosis complications associated with the factor V Leiden mutation in pregnancy, using a lot of women with complications of pregnancy selected from our casuistic. We concluded that factor V Leiden mutation and resistance to activated protein C are important risk factors for pregnancy complications. The screening for resistance to activated protein C with FV deficiency plasma is recommended in all pregnant women with vascular placental complications or history of pregnancy complications. [ABSTRACT FROM AUTHOR]