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Aims: A new generation of building materials is produced using computing and digital methods. Recombinant building materials have created new perspectives. The main purpose of research is to study, analyze and prioritize the computing of new materials in accordance with environment. The practical purpose of the research is to explain the concept and present strategies based on the use of appropriate materials to achieve the model of "healthy city".
Methods: It is qualitative-quantitative research in terms of methodology. Qualitative steps lead to the explanation of the conceptual framework of the research, and quantitative steps lead to prioritization of the strategies base on online questionnaire. Kappa coefficient has been used to confirm the reliability. A total of 386 questionnaires were collected and the results were analyzed using Spearman correlation.
Findings: Among the ten items extracted about the new materials used, four items with a high degree of significance were obtained: 1- Exposure to direct sunlight, 2- Material health (MSDS), 3- Ease of replacement and replacement, and 4- Degree of moisture absorption, respectively. 
Conclusion: The increasing risk of pandemics shows that the concept of the healthy city is not possible without the computing of new materials; an interdisciplinary field that requires a combined approach of green chemistry, biocomputing and materials-based computing. Computing new materials is an effective way to achieve the healthy city which is in need of "environmental education" and the "healthy city management" skill development.

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In the present work, we describe the synthesis of silver nanoparticles (Ag-NPs) using seed aqueous extract of Psidium guajava (PG) and its antibacterial activity. UV–visible spectroscopy, X-ray diffraction (XRD), Fourier transform infra red spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray energy dispersive spectrophotometer (EDAX) were performed to ascertain the formation of Ag-NPs. It was observed that the growths of Ag-NPs are stopped within 35 min of reaction time. The synthesized Ag-NPs were characterized by a peak at 446 nm in the UV–visible spectrum. XRD confirmed the crystalline nature of the nanoparticles of 10-20 nm size. The XRD peaks at 38◦, 44◦, 64◦ and 77◦ can be indexed to the (1 1 1), (2 0 0), (2 2 0) and (3 1 1) Bragg’s reflections of cubic structure of metallic silver, respectively. The FTIR result clearly showed that the extracts containing OH as a functional group act in capping the nanoparticles synthesis. Antibacterial activities of Ag-NPs were tested against the growth of Gram-positive (S. aureus) using SEM. The inhibition was observed in the Ag-NPs against S. aureus. The results suggest that the synthesized Ag-NPs act as an effective antibacterial agent. It is confirmed that Ag-NPs are capable of rendering high antibacterial efficacy and hence has a great potential in the preparation of used drugs against bacterial diseases. The results confirmed that the (PG) is a very good eco friendly and nontoxic source for the synthesis of Ag-NPs as compared to the conventional chemical/physical methods.

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Aims: In the indoor space, the temperature and relative humidity are often controlled and even without the use of heating and cooling systems, the temperature and relative humidity changes in the indoor space are less than the outdoor space. Buildings are relatively protected against pollutants of external origin. The main problem of the research is to analyze and investigate the environmental effects of exposure to particles and gases that are released or produced inside the house; And especially the effect of these pollutants on the health of residents.

Methods: The research method of this study is based on logical reasoning. The scientific foundations of the subject are analyzed with a quasi-experimental approach, and the results are presented with the combined modeling method. In terms of methodology, in this research, chemical reactions carried out in indoor spaces are investigated. In this direction, the mechanisms and kinetics of reactions, the characteristics of different surfaces and the effect of factors such as light and temperature
will be investigated.

Findings: A healthy environment is a prerequisite for a healthy life for residents; This is as important in closed spaces as in open and semi-open spaces. Research
findings emphasize the special importance of micropollutants and their impact on residents' health.

Conclusion: Clarifying the importance and role of building materials in indoor air health is one of the most important achievements of this research. An achievement that above all emphasizes the importance of environmental education in promoting healthy buildings, bio-computing and the use of environmentally friendly materials.

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Objective: Dendrimers are three-dimensional nanostructures that have numerous applications in medicine, including drug delivery and imaging. Although anionic dendrimer polyethylene glycol–citrate has a high potential to increase solubility of water-insoluble drugs and drug delivery, its multi-step synthesis procedure is time consuming. In addition, toxic substances such as dichloromethane are used in its synthesis procedure. In this study, we have developed a simple one-step synthesis method using green chemistry. Methods: We examined four different methods to improve the synthesis method of this dendrimer. Products were characterized by FTIR, LC-MS and DLS. Cytotoxicity was assessed by the XTT method. Results: We synthesized a G2 polyethylene glycol–citrate dendrimer in one-step without purifying G1. This process was chosen as a beneficial method for synthesis of the G2 dendrimer. When compared with previous methods, this procedure had higher efficiency and greatly reduced response. This procedure used nontoxic materials. XTT assay results showed that this dendrimer created by green chemistry had no cytotoxicity in Hela and Vero cells up to a concentration of 800 µM. Conclusion: One-step synthesis of anionic polyethylene glycol-citrate G2 dendrimer is a simple, beneficial production method. The dendrimer is biocompatible and can be used as a suitable carrier for drug delivery purposes.