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The purpose of this study is to conduct a thorough examination of the direct and indirect impacts of increasing the quantity of heavy WO3 on gamma-ray transmission, shielding and mechanical properties for some selected barium-phosphate-tungsten glasses. Accordingly, mechanical properties of barium-phosphate-tungsten oxides with chemical formula (50-x)P2O5-50BaO-xWO3 (x = 0.0(S1), 5.0(S2), 10(S3), and 15(S4)) mol% was evaluated using Makishima-Mackenzie model. Next, newly online Phy-X/PSD software and Monte Carlo code were used to examine the gamma radiation characteristics. Gamma-ray transmission factor (TF) values were calculated for S1, S2, S3 and, S4 glass samples for a range of well-known radioisotope energies such for 67Ga, 57Co-57, 111In-111, 133Ba, 201Tl, 99 mTc, 51Cr, 131I, 58Co, 137Cs, 60Co. The total packing density (Vt) was enhanced from 0.589 for S1 glass sample (free with WO3) to 0.605 for S4 glass sample (with highest WO3 =15 mol%). The total energy dissociation (Gt) of the investigated glasses was increased with increasing the WO3 content: from 51.7 (kJ/cm3) for S1 glasses to 52.45 (kJ/cm3) for S4 glasses. All mechanical moduli were improved with increasing the tungsten trioxide concentration in the studied glasses. Poisson's ratios were increased with increasing the WO3 concentration. The trend of linear (LAC) and mass attenuation (MAC) coefficients were followed as: (LAC, MAC) S1 < (LAC, MAC) S2 < (LAC, MAC) S3 < (LAC, MAC) S4. Half (HVL) and tenth (TVL) value layers have the trend as (HVL, TVL) S1 > (HVL, TVL) S2 > (HVL, TVL) S3 > (HVL, TVL) S4. The effective atomic number (Zeff) and electron density (Neff) have the same trend. The lowest transmission Factor (TF) values for all glass specimens were examined at a thickness of 3 cm. Furthermore, the S4 sample displayed the least transmission tendency across all glass thicknesses evaluated. © 2022 The Authors Princess Nourah bint Abdul Rahman University Researchers Supporting Project Number (PNURSP2022R149).

Wastewaters from the textile industry are hazardous effluents containing toxic complex components that without appropriate treatment severely impact the environment; causing harmful effects to the aquatic ecosystems, as well as to human health. The present study extensively reviews the dyes and chemicals utilized in the textile industry focusing on the traditional treatment methods -chemical, biological, physical and hybrid systems-for their removal from industrial wastewaters. In addition, a critical analysis on Internet of Things based management systems for their remote monitoring and control of the water quality is reported. It was found the absence of a common platform for the integration of the different traditional treatment methods in association with modern technologies is the main limiting factor for an effective sustainable manufacturing. Therefore, it is the aim of this research to broaden the scope of potential solutions, proposing cost-effective high-performing combined strategies with promising benefits for future industrial applications.

In recent decades, naturally growing mosses have been used successfully as biomonitors of atmospheric deposition of heavy metals and nitrogen. Since 1990, the European moss survey has been repeated at five-yearly intervals. In 2010, the lowest concentrations of metals and nitrogen in mosses were generally found in northern Europe, whereas the highest concentrations were observed in (south-)eastern Europe for metals and the central belt for nitrogen. Averaged across Europe, since 1990, the median concentration in mosses has declined the most for lead (77%), followed by vanadium (55%), cadmium (51%), chromium (43%), zinc (34%), nickel (33%), iron (27%), arsenic (21%, since 1995), mercury (14%, since 1995) and copper (11%). Between 2005 and 2010, the decline ranged from 6% for copper to 36% for lead ; for nitrogen the decline was 5%. Despite the Europe-wide decline, no changes or increases have been observed between 2005 and 2010 in some (regions of) countries.

For the Li–N system samples were obtained at pressures of nitrogen from 1 to 10 atm. Energy-dispersive X-ray (EDX) spectrum of a sample of Li–N subjected to degradation shows that lithium nitride turned into carbonate as evidenced by the predominant content of carbon and oxygen. Upon synthesis of lithium nitride at a positive pressure of nitrogen, the β-modification is formed, which can be achieved at a pressure 500 times lower than that described in literature, required to create a high-pressure phase. The increase in carbon content with increasing of synthesis pressure of lithium nitride confirms the change in stoichiometry of its structure formed with high nitrogen content.

article i nfo Instrumental neutron activation analysis (INAA) was applied to determine elemental concentrations in some fish species collected frome the Romanian sector of Danube River at km 1049, near the entrance in Romania (Carassius auratus gibelio, Ctenopharingodon idella, Rutilus rutilus and Silurus glanis) and km 630 (Acipenser ruthenus). Concentration values of 32 elements (Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Lu, Na, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Zn and Zr) in calcined fish samples were obtained based on long half-life radionuclides. Bioaccumulation factors (BAF) in fresh fish relative to Danube water (km 1049) were assessed and compared with literature data.

Gas chromatography–mass spectrometry was used for the determination of 16 priority polycyclic aromatic hydrocarbons (PAHs) in surface soils from seventeen areas in Southeast Romania, including sites placed in the vicinity of Galati iron and steel plant and Lower Prut Meadow natural reserve in Galati County. The total concentration of PAHs (TPAHs) in the investigated soils ranges from 0.003 mg/kg to 38.524 mg/kg dry weight. According to Romanian legislation for trace organic compounds in soils of different uses, the amounts of PAHs in soils from the industrial zone exceed the normal values for the majority of individual PAHs. The lowest concentrations were found in soils sampled from the protected area of Lower Prut Meadow natural reserve and the highest near a zootechnique farm in the Prut River basin, where the alert levels exceeded for the less sensitive area in the case of TPAHs and benzo[b]fluoranthene and for the sensitive area in the case of chrysene, benz[a]anthracene, benzo[k]fluoranthene and benzo[g,h,i]perylene. The sources of PAH contaminating soils are complex, being of both pyrogenic and petrogenic origins.

In this work the sensitivities of minor elements in a standard steel sample EURONORM-CRM No. 085-1 irradiated with beams of 5.5 MeV protons and 5 MeV deuterons have been determined both by regular proton- (p-PIGE) and deuteron-induced prompt gamma-ray emission (d-PIGE) methods and with the selection of the (p, n) and (d, n) reaction channels, measuring the neutron–gamma coincidences. A check on the elemental composition of the steel standard has also been carried out using combined INAA and PIXE and quantitative determinations have been done for some elements whose concentrations were not specified by the manufacturer, such as Al, As, Cr, Mo, Na, Ni, W. This complex study has resulted in a significant improvement of the sensitivities for some minor elements in steel by reducing the background and increasing the peak-to-background ratio in the coincident prompt gamma-rays spectra as a result of the elimination of the competing nuclear reactions originating from isotopes of the adjacent elements in the periodic table, present in the steel target. This extension of the PIGE method could be adapted by any analyst with the necessary equipment for the analysis of a wide variety of matrices that are refractory enough to withstand the heating effect of the bombarding beam, taking into account that this type of experiment requires longer irradiation times.

In this work a complex study of the nuclear and spectral interferences which appear in gold determination by 14 MeV neutron activation analysis of Romanian auriferous alluvial sands and rocks has been accomplished. The contribution of the nuclear interfering elements – Hg and Pt – to the concentration of gold in the samples is minimum in the case of the nuclear reactions 197Au(n, 2n)196Au, 197Au (n,2n)196mAu and 197Au(n, n′)197mAu. As regards the spectral interferences, these are minimum in the case of using the reactions 197Au(n, n′)197mAu and 197Au (n, 2n)196Au and are due to Rb, Ti and V for the short irradiation and to Se for the long irradiation. We propose two methods of gold determination in auriferous alluvial sands and rocks in the range 20–2500 ppm – the minimum value of 20 ppm being at the level of an economic extraction – in the optima conditions established by us so that the systematic errors of analysis due to the gold accompanying elements should be considerably diminished: a method using short irradiation (25 s) and NaI(Tl) spectrometry for the measuring of the induced gamma radioactivity in the samples and a method using long irradiation (3000 s) and Ge(Li) spectrometry. The data presented in this paper can be adapted by other analysts to the rapid determination of gold in a variety of alluvial sands and rocks.

The sensitivities of minor elements analysis in a standard steel sample irradiated with 5 MeV deuterons have been determined by the regular deuteron-induced γ-ray emission (d-PIGE) method and with the selection of the (d, n) reaction channel by measuring γ–n coincidences. This approach has resulted in a significant improvement of the sensitivity of the analysis. A comparative study with the published results using protons as projectiles was also made.

The concentration of minor elements in a standard steel sample has been determined by irradiation with protons of 5.5 MeV. The steel sample has been analyzed with the regular PIGE method and with the selection of the (p, n) reaction channel by measuring γ-n coincidences. This approach has resulted in a significant improvement of the sensitivity of the analysis.