Synthesis Of Mg/Al Hydrotalsite-Magnetite As CN- Ion Adsorbent On Wastewater Tapioca Industry

Cyanide compounds contained in tapioca industrial wastewater are relatively high, so it is necessary to reduce cyanide levels. This study utilizes the hydrotalcite-magnetite ability to adsorption of CN- ions. The composite formation process is carried out by mixing the magnetite phase at the stage of hydrotalcite-magnetite synthesis. The characterization of X-Ray Diffraction (XRD) shows reflection of the magnetite peak of 2θ 21.42°; 30,28°; 33.40°;35.65° and 37°. While the peak of hydrotalocites at an angle of 11.66° ; 23,33° ; 34,80° ; 60,92° ; and 62.21°. This result is supported by ir spectra on hydrotalocytes shown by O-H group at wave number 3441 cm-1, O=C-O at wave numbers 1359 cm-1, M-O and M-OH at wave numbers 964 cm-1, 797 cm-1 and 673 cm-1. Fe-O and Fe-OH absorption from magnetites at wave numbers 892 cm-1, 798 cm-1 and 629 cm-1. 0.4 grams of hydrotalcite-magnetite at 30 minutes of stirring absorbed 0.0490 mg/L of cyanide from tapioca liquid waste solution. The value of adsorption capacity is 0.022 mg/g and the adsorption efficiency is 87.96%. The hydrotalcite-magnetite adsorption method is superior to aerob and anaerobic methods using bacteria in the tapioca industry.

Antibiotics Contaminated Irrigation Water: An Overview on Its Impact on Edible Crops and Visible Light Active Titania as Potential Photocatalysts for Irrigation Water Treatment

Sub-therapeutic levels of antibiotics (ABs) are given to animals and poultry to promote growth and reduce disease. In agricultural environments, ABs reach croplands via animal manure used as fertilizer and/or ABs-contaminated water used for irrigation. The continuous discharge of ABs into the ecosystem raises growing concerns on the ABs contamination of edible crops. Tetracyclines (TCs) are among the most widely used ABs around the world. In this review, we discuss the contamination of irrigation water with TCs, its impact on edible crops, and the potential risks of crop contamination with TCs on human health. We propose solar-mediated photocatalytic degradation using Titania (TiO2) photocatalyst as a promising method to remove TCs from irrigation water. The photocatalytic activity of TiO2 can be enhanced by chemical modification to expand its activity under visible light irradiation. Herein, we aim for providing literature-based guidance on developing a visible light–active TiO2-based system to degrade TCs and other ABs in water streams. We include a summary of recent advances on this topic based on three main modification methods of Titania: metal/non-metal/mixed doping, composite formation, and heterojunction construction. Among the investigated photocatalysts, Fe2O3-TiO2/Fe-zeolite and the N-doped TiO2/rGO immobilized composite catalysts were found to be very efficient in the degradation of TCs under visible light irradiation (i.e., 98% degradation within 60 min). Most immobilized TiO2 based composite systems exhibited improved performances and hence we highlight these as efficient, cost effective and ecofriendly photocatalysts for the degradation of TCs in irrigation water.

The Potential of Al2O3–ZrO2-Based Composites, Formed via CSC Method, in Linear Infrastructure Applications Based on Their Mechanical, Thermal and Environmental performance

Ceramic-ceramic composites have been prepared using the centrifugal slip casting method (CSC). The method has so far been mainly utilized in making ceramic-metal composites. Al2O3–ZrO2 composites have been obtained with different shares of ZrO2, i.e., 15, 50 and 75 vol pct, respectively. Prior to sintering the composite samples, the rheological properties of the casting slips were investigated and thermogravimetric tests were performed. Upon sintering, all three series of the ceramic composites showed a density close to 100 pct and no microcracks or delamination. Phase, microstructural and mechanical investigations were carried out to determine what effect the share of ceramics has on the composites produced. An increase in the share of ZrO2 in the Al2O3–ZrO2 composite leads to a reduction in the growth of Al2O3 grains and a decrease in the average hardness. Cross-sectional hardness testing of the composites showed no evident gradient in any of the samples. Life cycle analysis (LCA) results indicate that the further optimization of the composite formation process, including up-scaling, allows to obtain Al2O3–ZrO2-based pipes possessing more favorable environmental characteristics compared with materials conventionally used for linear infrastructure, which is important in light of the global transformation toward sustainable construction and the circular economy. Graphical abstract

Application of Nanosilicon to the Sintering of Mg-Mg2Si Interpenetrating Phases Composite

The new in situ fabrication process for Mg-Mg2Si composites composed of interpenetrating metal/intermetallic phases via powder metallurgy was characterized. To obtain the designed composite microstructure, variable nanosilicon ((n)Si) (i.e., 2, 4, and 6 vol.% (n)Si) concentrations were mixed with magnesium powders. The mixture was ordered using a sonic method. The powder mixture morphologies were characterized using scanning electron microscopy (SEM), and heating and cooling-induced thermal effects were characterized using differential scanning calorimetry (DSC). Composite sinters were fabricated by hot-pressing the powders under a vacuum of 2.8 Pa. Shifts in the sintering temperature resulted in two observable microstructures: (1) the presence of Mg2Si and MgO intermetallic phases in α-Mg (580 °C); and (2) Mg2Si intermetallic phases in the α-Mg matrix enriched with bands of refined MgO (640 °C). Materials were characterized by light microscopy (LM) with quantitative metallography, X-ray diffraction (XRD), open porosity measurements, hardness testing, microhardness testing, and nanoindentation. The results revealed that (n)Si in applied sintering conditions ensured the formation of globular and very fine Mg2Si particles. The particles bonded with each other to form an intermetallic network. The volume fraction of this network increased with (n)Si concentration but was dependent on sintering temperature. Increasing sintering temperature intensified magnesium vaporization, affecting the composite formation mechanism and increasing the volume fraction of silicide.

Verbal compression as the implementation of universal tendency of compensative processes in the lingual world

The objective of the research is to describe mental and verbal primary and secondary (modern) compressive transformations. Main research methods are represented by the descriptive and structural ones making it possible to demonstrate characteristic aspects of univerb- and composite-formation (including abbreviation) as the processes corresponding to the essence of verbal compression. A tendency to compensative processes in speech and language is represented by the formations capable of complete substituting of the analytical primary names of objects, signs, and actions of the reality. In other words, a compensative process implies, apart from its main task, – balancing of the number of verbal units, – contraction of sounding duration and writing form of those units, i.e., substitution of analytical, multicomponent, nominative formations for the synthetic, monocomponent ones; that means saving time and space as the means of information conveyance. That tendency originates in the Common Slavic period. Univerbs and abbreviations, including telescopisms, are real forms of nominative units of analytical representation (word combinations) and potential alternative forms of synthetic (verbal) nominative units as the same time.

Preparation, Characterization and Evaluations of Carbon-Doped Ag/Fe/TiO2 Mesoporous Nanocomposite Photocatalyst for Degradation of Methylene Blue and Congo Red

Carbon doped silver/iron/TiO2 nanocomposite is synthesized via the solvothermal technique. Titanium tetraisopropoxide is used as a TiO2 source. The composite samples are characterized by different physicochemical methods, including nitrogen adsorption–desorption analysis, transmission electron microscope, scanning electron microscope, X-ray diffraction, photoluminescence, UV-vis, Fourier-transform infrared, and Energy dispersive X-ray spectroscopy. The nanocrystalline structure of the samples with anatase phase having a tetragonal shape is shown by the XRD and TEM analysis. The photo-absorption boundary of pure TiO2 expands into the visible light region due to composite formation, shown by analysis of UV-vis data. An increase in the degree of electron–hole couple segregation is shown via photoluminescence analysis. N2 adsorption–desorption analysis manifests the higher surface area of samples along with mesoporous nature. The high photodegradation action is shown by the composite samples as compared to pure mesoporous TiO2.