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A detailed study was carried out to compare the removal of Reactive Blue 221 and Red X-5GN dyes using raw Helianthus Annuus L. seed shell as a natural adsorbent. There is no study in the literature for comparing the treatment of these anionic and cationic dyes using the current seed shell in raw form. Bringing a natural waste to the economy that can compete with adsorbents such as activated carbon commercially used in dye removal, will offer important advantages. The variation of initial pH value, shell dosage, contact time and, initial dye concentration was investigated. Reactive Blue 221 was successfully removed at pH 2 with a treatment efficiency of above 90%, while Red X-5GN was treated at pH 4 with a removal efficiency of 97%. Appropriate adsorbent dosages were 4 and 10 g/L for Reactive Blue 221 and Red X-5GN, respectively. Adsorption data of two dyes fitted very well to the pseudo-second-order reaction model with R-2 values of 0.979-0.999. The data were best repreŞented by the Langmuir model for Reactive Blue 221 with an R-2 of 0.986. Freundlich isotherm was the most suited model for adsorption of Red X-5GN dye with an R-2 of 0.996. The maximum uptake capacities were found to be 27.40 mg/g for Red X-5GN and 30.58 mg/g for Reactive Blue 221. The results showed that the conditions of adsorption for each dye can be significantly different. Besides, the potential of this seed shell as an eco-friendly and low-cost adsorbent was exhibited with perfect treatment results. [GRAPHICS]

Context Community college students, representing more than one-third of U.S. undergraduates, are a diverse population of young people motivated to seek higher education who are at elevated risk of unintended pregnancy. However, it is unknown how well prepared they are to prevent pregnancy and what they think about it in terms of their educational aspirations. Methods In-depth interviews were conducted with 57 students aged 18-25, inclusive of all genders, in three community colleges in California in 2015. Content analysis was used to code data and identify themes. Results All participants reported strong desires to prevent pregnancy in the next year and perceived their pregnancy risk as low, but many reported unprotected sex with opposite-sex partners. Participants had specific timelines for completing their degrees and believed pregnancy would make that far more challenging, but would not ultimately prevent them from achieving their goals. Female students expressed concern about the risks of exacerbated poverty, housing instability and unachieved career goals. Participants had little knowledge of their pregnancy risks and of the health benefits, side effects or effectiveness of contraceptives. They held negative beliefs about hormonal contraception (including emergency contraception, IUDs and the implant), fearing long-lasting effects and infertility. Gay or bisexual students shared concerns about contraceptives, although several were using methods for noncontraceptive reasons. Conclusion Many community college students not desiring pregnancy have limited awareness of pregnancy risk and prevention.

This study presents 5-hydroxymethylfurfural removal from waste hand paper hydrolysate using activated carbon adsorption. In this context, the effects of adsorbent dosage, initial 5-hydroxymethylfurfural concentration, temperature, and agitation speed on 5-hydroxymethylfurfural adsorption were investigated. Moreover, isotherm and kinetic evaluations were performed using Langmuir, Freundlich, and Temkin models. The experimental data were correlated with zero, first, pseudo-first, and Weber–Morris intraparticle diffusion models. The toxicity of 5-hydroxymethylfurfural was determined using the resazurin reduction assay, and the EC50 of 5-hydroxymethylfurfural in the hydrolysate was found as 192 mg/L. Most convenient 5-hydroxymethylfurfural adsorption was obtained at 5 g/L AC dosage, 40 °C and 150 rpm agitation speed. The highest 5-hydroxymethylfurfural removal efficiency was 92% at 7 g/L AC dosage. The adsorption data fitted best with the Langmuir isotherm model with a maximum uptake capacity of 70.92 mg/g (R2: 0.96). The zero-order reaction kinetic model was the most suitable one among the others inspected. It was determined that intraparticle diffusion was not the rate-limiting step. This study showed that waste hand paper hydrolysate can effectively be detoxified by activated carbon adsorption. © 2019, Islamic Azad University (IAU).