A sensitive and simple method using magnetic multi-walled carbon nanotube (MWCNTs-FeO MNP), as the adsorbent, has been successfully developed for extraction and pre-concentration of arsenic, lead and cadmium with detection by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The nanosorbent was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction pattern (XRD), vibrating sample magnetometer (VSM) and transmission electron microscopy (TEM). The key factors affecting the signal intensity such as pH, adsorbent amount, etc. were investigated. Under optimal conditions, the limits of detection (three-time of signal to noise ratio, S/N 3) were 0.3, 0.6, 0.3 ng/mL for arsenic, lead and cadmium, respectively. Application of the adsorbent was investigated by the analysis of water, milk, Indian rice and red tea. The experimental data was analyzed and obeyed Langmuir and Freundlich adsorption models. The kinetic data was fitted to the pseudo-second-order model. Thermodynamic studies revealed the feasibility and exothermic nature of the system.

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The inclusion of a polyamidoamine dendrimer in a silica sol-gel yielded a solid nanosorbent that was used for the preconcentration, extraction, and determination of citalopram in hospital waste water, hemodialysis solution, and some drinking water. The method was developed by applying a novel nanosorbent for the solid-phase microextraction of citalopram, containing a silica sol-gel reinforced by polyamidoamine second-generation dendrimer, which was protected by a polypropylene hollow fiber. Plackett-Burman design and central composite design were utilized to evaluate the significance of several factors on the extraction efficiency. The adsorption mechanism and thermodynamic and kinetic aspects were studied. The adsorption process was exothermic and well fitted to the Bangham equation kinetic model. Under optimal conditions, the presented method was liner in the range of 0.05-100 μg/mL. The limits of detection of quantification of citalopram were 0.0095 and 0.031 μg m/L, respectively.

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The study presents the synthesis of nano-thiamine hydrochloride structure (NTH) using sol-gel method by hydrolysis of tetraethyl orthosilicate with ethanol and water mixture as silica source and nitric acid as catalyst support in which thiamine hydrochloride nanocrystals were dispersed in the silica glassy matrix. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The morphological observation of the SEM results reveals that the nano-thiamine hydrochloride composites are in the range of 5–15 nm in size.

In this age of transition from decades of turmoil and instability in urban areas, urban centers validate their prestige and importance as a commercial, cultural and recreational center. Urban centers as the housing and shelter for millions of people and visitors will facilitate and improve human interaction. Since the city is very complex, existence and attendance of cycles of declining and wane, reform and reconstruction are obvious. At the best form, appearance of a city will be realized from its center & heart. Recently, in western countries, having vibrant and dynamic urban centers has caught the attention of many scholars. Actually creating an environment where social interaction is high and gives people a sense of vitality. On the other hand, to include such dynamism in context of an urban center, it needs adequate respondents. Therefore, in this paper, at firs the criteria for responsive environments, characters of a vibrant city center and the main & common features between them is introduced, using the analytic hierarchy process (AHP), criteria are weighted and prioritized. The results show that, sustaining the above criteria and codifying proposed policies and strategies, helps to recreate the historic core of Qazvin city.

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Lost urban spaces are unique spaces inside the city which have not been used at all or significantly. In other words, they are unpleasant urban areas which have no positive relationship with surrounding environment and users in redesigning process of spaces. Hence, organization and reclamation of lost and left spaces through performance injection from resources and wealth which give identity is a part of technologies which can be experienced and tested by experts in order to provide places for presence, spending time, observing and be seen from these excluded urban spaces. With this description and the importance of the subject, the present paper sought to introduce urban lost spaces and consider criteria in order to revive identity in these spaces using Analytical Hierarchical Process (AHP) model and also to consider the succeeded level of the recovery plan of identity in Akhoond district in Qazvin using a descriptive-analytical method. The results of the present study indicated that the recovery plan of identity in Akhoond district was not successful due to the lack of attention to main criteria of giving identity to spaces and it has not transferred identity, mobility and fixation to its residents.