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To evaluate the effect of flux, activator and co‐activator on solid state synthesis of SrAl₂O₄: Eu^2 +, Dy^3 + phosphor, where boric oxide, europium oxide and dispersium oxide were used, respectively.

To optimise synthesis condition of long lasting phosphorescence SrAl₂O₄ phosphor, boric oxide was used as a flux. To improve relative intensity of SrAl₂O₄: Eu^2 + phosphor, the critical concentration of Eu^2 + was determined. The effect of various concentration of co‐activator on afterglow properties, the effect of Dy^3 + ion on the emission and excitation spectra were examined.

The SrAl₂O₄: Eu^2 +, Dy^3 + phosphor powders have been synthesised by solid state reaction method. The result of XRD patterns indicated that, addition of 5 mol% B₂O₃ enhanced the formation of SrAl₂O₄ at 1,200°C. Investigation on the variation of emission intensity of different phosphors containing different amounts of Eu^2 + revealed that after 6 mol% of Eu^2 + concentration, quenching process occurred. Dy^3 + formed trap levels and results demonstrated that increasing concentration of Dy^3 + up to 5 mol% reduced the relative intensity and increased the decay time.

Using B₂O₃ as a flux and solid state reaction method for preparation of this phosphor is in good agreement with industrial production and make it economic, because of reduced sintering temperature.

The purpose of this paper is to evaluate the effect of copolymer and starting material concentrations in homogeneous precipitation synthesis of Yttria nanoparticles and red‐emitting nanophosphors Y₂O₃:Eu³⁺. N‐isopropylacrylamide and acrylic acid (NIPAM/AAc) and urea are used.

To optimise synthesis condition of Y₂O₃:Eu³⁺ nanophosphor NIPAM/AAc copolymer was used as a modifier and the effect of various concentration of yttrium ions, urea and precipitation time on size, morphology and emission spectra were investigated.

Using NIPAM/AAc copolymer shows significant improvement on size and dispersion of nanoparticles. It is found that yttrium concentration, varying between 0.006 and 0.03 M, has a profound impact on the average size of particles, which systematically increases from 65 to over 165 nm. The rate of precipitation reaction, however, is shown to be independent of yttrium concentration. In contrast, as urea concentration increases from 0.2 to 5 M, the average particle size exhibits a gradual decrease from 183 to 70 nm. At extremely high urea concentration such as 5 M, a significant level of inter‐particle agglomeration is observed.

Based on this paper, the authors have successfully prepared some promising nanophosphors. The nanoparticles are studied by X‐ray diffraction, transmission electronic microscopy, zeta sizer, Infra red and photoluminescence spectroscopy.

Concrete, the second most used material in the world, surpassed only by water, relies on a vast amount of cement. The process of cement production emits substantial amounts of carbon dioxide (CO₂). Consequently, it is crucial to search for cement alternatives. Geopolymer concrete (GC) uses industrial by-product material instead of traditional cement, which not only reduces CO₂ emissions but also enhances concrete durability. On the other hand, the disposal of concrete waste in the landfills represents a significant environmental challenge, emphasising the urgent need for sustainable solutions. This study aimed to investigate waste concrete's best form and rate as the alternative aggregates in self-compacting and ambient-cured GC to preserve natural resources, reduce construction and demolition waste and decrease pertinent CO₂ emissions. The binding material employed in this research encompasses fly ash, slag, micro fly ash and anhydrous sodium metasilicate as an alkali activator. It also introduces the best treatment method to improve the recycled concrete aggregate (RCA) quality.

A total of25%, 50% and 100% of coarse aggregates are replaced with RCAs to cast self-compacting geopolymer concrete (SCGC) and assess the impact of RCA on the fresh, hardened and water absorption properties of the ambient-cured GC. Geopolymer slurry was used for coating RCAs and the authors examined the effect of one-day and seven-day cured coated RCA. The mechanical properties (compressive strength, splitting tensile strength and modulus of elasticity), rheological properties (slump flow, T500 and J-ring) and total water absorption of RCA-based SCGC were studied. The microstructural and chemical compositions of the concrete mixes were studied by the methods of energy dispersive X-Ray and scanning electron microscopy.

It is evident from the test observations that 100% replacement of natural aggregate with coated RCA using geopolymer slurry containing fly ash, slag, micro fly ash and anhydrous sodium metasilicate cured for one day before mixing enhances the concrete's quality and complies with the flowability requirements. Assessment is based on the fresh and hardened properties of the SCGC with various RCA contents and coating periods. The fresh properties of the mix with a seven-day curing time for coated RCA did not meet the requirements for self-compacting concrete, while this mix demonstrated better compressive strength (31.61 MPa) and modulus of elasticity (15.39 GPa) compared to 29.36 MPa and 9.8 GPa, respectively, for the mix with one-day cured coated RCA. However, incorporating one-day-cured coated RCA in SCGC demonstrated better splitting tensile strength (2.32 MPa) and water absorption (15.16%).

A potential limitation of this study on SCGC with coated RCAs is the focus on the short-term behaviour of this concrete. This limited time frame may not meet the long-term requirements for ensuring the sustained durability of the structures throughout their service life.

This paper highlights the treatment technique of coating RCA with geopolymer slurry for casting SCGC.

Food insecurity exists when access to nutritionally sufficient and secure foods or the ability to obtain admissible foods in socially acceptable ways is limited or uncertain. Food insecurity is most likely associated with chronic disease. However, research into the possible relationship between food insecurity and cancer, the world’s second leading cause of death, is limited. The purpose of this study was to determine the level of food insecurity as well as the associated socioeconomic characteristics among cancer patients.

A cross-sectional study was conducted on 240 cancer patients in Iran. The socioeconomic and 18-item U.S. Department of Agriculture (USDA) Food Security Questionnaires were used to measure general and socioeconomic characteristics, as well as food security status.

The prevalence of food insecurity was 25.4% in the form of hunger and 52.5% in the form of hidden hunger. Only 22.1% of the patients were food secure. The results of the logistic regression analysis revealed that having children under 18 years old (P = 0.035), economic status (P < 0.001), age of the patient (P = 0.001), educational level of household’s head and his spouse (P = 0.044 and P = 0.045, respectively, had statistically significant relationships with food insecurity.

Cancer patients have a high rate of food insecurity. Considering the importance of food security for effective cancer treatment, the health system’s attention to this issue, particularly by policymakers, appears to be required.

Examining the impact of socioeconomic status (SES) and expenses spent on food preparation on nutritional intake has always been one of the critical concerns for policymakers. This study aims to investigate the association between household food expenditure as well as SES and dietary nutrient intake in Kermanshah, Iran.

In this cross-sectional study, households were randomly selected from different strict in Kermanshah, Iran. Data were collected with an SES questionnaire, a demographic data collection form, a weekly food purchase checklist and a food record. The authors performed the analysis of covariance to determine the relationship of dietary nutrient intake of study participants across quintile categories of SES and total food expenses per day.

Out of 125 households, 119 households including 401 people finished the study. A significant association was observed between higher SES and higher intake of vitamin B2 (p-value = 0.03). Moreover, the household members at the top level of total food expenses per day had significantly greater dietary nutrient intake of energy (p < 0.001), potassium (p < 0.001), magnesium (p < 0.001), calcium (p < 0.001), zinc (p < 0.001), vitamin B2 (p < 0.001), B6 (p < 0.001), B12 (p = 0.002) and vitamin C (p = 0.04).

In our study, higher dietary nutrient intake was observed in the household members at the highest level of total food expenses daily as well as SES. Therefore, governments and policymakers should pay basic attention to optimizing food costs and improving the economic status of people.