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INTRODUCTION: Although increasing attention is paid to HIV/AIDS, patients with HIV still experience several barriers to self-care. These barriers have been previously identified in small quantitative studies on women with HIV, but qualitative studies are required to clarify barriers to self-care. METHODS: we conducted our study using the grounded theory methodological approach. A total of 28 women with HIV and their family members, were interviewed. The data were analyzed with the Corbin and Strauss method (1998). RESULTS: the key barriers to self-care in women with HIV/AIDS included social stigma, addiction, psychological problems, medication side-effects and financial problems. CONCLUSION: women with HIV/AIDS face several barriers to self-care. Therefore, when designing self-care models for these women, social and financial barriers should be identified. Mental health treatment should also be incorporated into such models and patients' access to health care services should be facilitated.

In the present work, a polyvinyl chloride (PVC)/magnetite nanocomposite membrane (NCM) was fabricated by a casting technique for the removal of Cd2+ and Pb2+ ions from aqueous solutions. Magnetite (Fe3O4) nanoparticles (NPs) were synthesized from the Ramalina sinensis plant extract. The synthesized materials were characterized by UV–visible, X-ray diffraction, Fourier-transform infrared, field emission scanning electron microscopy, energy-dispersive X-Ray spectrometry, Brunauer–Emmett–Teller (BET) surface area analysis, vibrating sample magnetometry, and thermal gravimetric analysis techniques. The fabricated NCM enhanced the adsorption capability of PVC without the use of any catalyst. The size of the magnetite NPs distributed in the NCM structure varied in the range of 25–70 nm. The specific surface area of the fabricated NCM was found to be $5.670~\mathrm{m}^{2}{\cdot }\mathrm{g}^{-1}$, which is approximately thrice greater than the reported value for pure PVC. The removal process of both Cd2+ and Pb2+ ions from aqueous solution showed the best fit to the Langmuir isotherm model. The maximum adsorption capacities of cadmium and lead ions were estimated to be 11.55 and $11.40~\mathrm{mg}{\cdot }\mathrm{g}^{-1}$, respectively. A kinetic investigation showed that the removal process of both metal ions can be well described by the pseudo-second-order kinetic model. The results obtained from adsorption investigations revealed that the synthesized NCM can be used for the removal of Cd2+ and Pb2+ ions from aqueous media.

Zeolite beta nanoparticles were used as a new asphaltene adsorbent for reducing asphaltene deposition during fluid injection into a silica sand pack. At first, the asphaltene adsorption efficiency and capacity of zeolite beta nanoparticles were determined by UV-Vis spectrophotometer. It was found that the proper concentration of nanoparticles for asphaltene adsorption was 10 g/L and the maximum asphaltene adsorption onto zeolite beta was 1.98 mg/m2. Second, two dynamic experiments including co-injection of crude oil and n-heptane (as an asphaltene precipitant) with and without use of zeolite beta nanoparticles in the sand pack was carried out. The results showed that the use of zeolite beta nanoparticles increased the permeability ratio and outlet fluid's asphaltene content about 22% and 40% compared to without use of nanoparticles, respectively. Moreover, a model based on monolayer asphaltene adsorption onto nanoparticles and asphaltene deposition mechanisms including surface deposition, entrainment and pore throat plugging was developed to determine formation damage during co-injection of crude oil and n-heptane into the sand pack. The proposed model presented good prediction of permeability and porosity ratios with AAD% of 1.07 and 0.07, respectively.