نشریه کاربرد شیمی در محیط زیست
پیاپی 43 (تابستان 1399)

Hydrogels are hydrophilic polymeric network of three dimensional cross linked structures that absorb substantial amount of water. Cross linking facilitates insolubility in water because of physical or chemical bonding. It also provides required mechanical strength and physical integrity to the hydrogels. There is an emerging demand and expanding interest in synthesis of hydrogel materials such as hydrogel based membranes and hydrogel composites. They can be applied in industrial separations, agriculture, biomedical purposes and reduction in environmental toxicity because of their good sorption abilities, resistance and low cost. Environmental degradation has a great impact on human health. Preventive measures taken to protect our environment will largely help in reducing illness and adverse health conditions. Research and advanced studies to understand various environmental issues, which have been plaguing us from a long time now, are looked up to with intense interests. The understanding of the causes and possible solutions for environmental problems calls for good sensors, to identify various causalities. Hence, a significant section on hydrogels used in sensing for environmental applications is presented here. With mounting issues of water scarcity and water pollution, recent applications of hydrogels for water remediation is also an important environmental application that we have addressed.

swimming pools As a recreational center and direct relevance of different human groups as a potential source of pollution, swimming pools (swimming pools)is a potential source of pollution, which in sound of lack of attention to health issues can be a source of transmission and outbreaks of bacterial, fungal and parasitic diseases. so the present study was carried out to study the pools of pool.

in this descriptive study of the active site of the saqqez city of 34 visitors and 34 sampling cases for کلرباقیمانده assay and pH of 15 and samples of microbial sampling were done randomly and with suitable culture medium to be tested on the samples. The amount of the remaining chlorine and the amount of water on the water were measured and recorded in a standard manner. the data were investigated using central inclination indices and person correlation coefficient.

all the items of کدورت were undesirable, and about 50 percent of the cases were favorable. On average, an average of 80 % of the safety points and swimmers average 60 % of their health points.

pay attention to disinfection, water control, turbidity and pH reduce contamination microbial is effective, but disinfection is the only way of prevention of the landfill is not. Health behaviors, including showers of soap before entering the pool, are likely to be effective from the pool of Bashawy and the basic sanitation of the pool environment in Decrease pollutions.

In this research, JSA method has been used to assess the risks and safety risks in Ilam gas refinery, . The risk was studied and then the results were modeled using PHA-pro software. The results showed that out of 15 identified risks, 7 had a risk number higher than 14, which can be said that approximately 46% of the activities were in the high risk area. Most of the values related to checking the seals were in the sulfur recycling unit, which resulted in spraying sulfur in the area outside the seals and causing burns and death. The corrective action was the use of face shields, work clothes and fireproof gloves. The next activity that had a high risk number was loading LPG, which resulted in improper installation of connections, gas leaks, fire / explosion, and damage to people and equipment. Be. It is clear that after the implementation of the control proposals, the number of high-risk cases has been reduced from 7 to 1, and the modeling bar chart has been moved to a safe area. In other words, before the control measures, 46% of the activities were in the high risk zone, 26% in the medium risk zone and 28% in the low risk zone. After the control measures, only 6% of the risks were in the high risk zone and 13% in The middle zone and 81% of them were in the low or safe risk zone.

Petroleum-based plastics or composite have created serious problems for the environment, and for this reason, researchers sought to produce alternative sustainable structures. Edible and degradable films were examples of materials that were produced and used for this purpose. Edible films are thin layers of edible material that can be placed on or between foods, but an edible coating is mainly placed on food products. Many studies have been conducted in this field for several years, but there is no comprehensive review in this field. The present study was conducted with the aim of investigating the performance of biodegradable films in food packaging. Various studies have used different materials such as starch, gelatin, chitosan, alginate, cellulose and etc. to produce biofilms, which, in addition to advantages such as biodegradability, have disadvantages such as weak mechanical and barrier properties. In this study, the effectiveness of biodegradable films in food packaging is investigated.

Recently, due to the increasing resistance of microorganisms to common antibiotics, the use of phenolic and antimicrobial compounds in medicinal plants has received special attention.

Gon extract was extracted by maceration method and their phenolic compounds were identified by HPLC, the antimicrobial effect of the extract was investigated in concentrations (25, 50 and 100 µg/ml). These bacteria included common microbes and fungi, including Streptococcus mutans, Streptococcus sanguinis, Streptococcus salivaris, Streptococcus subrinus, Escherichia coli, Icnella cordens, Pseudomonas aeruginosa and Klebsiella pneumoniae. Disc diffusion and MIC methods were used to investigate the antimicrobial activity of the extracts.

In the investigation of the effect of the desired extract on bacteria, it was found that the medicinal plant Gon has the least inhibitory effect against Streptococcus sanguinis bacteria and the most inhibitory effect on Candida glabrata fungus. The results of the MIC test also confirm these effects

According to the phytochemical results obtained from the extract of this research, it can be stated that the studied medicinal plant has antibacterial phenolic compounds. Therefore, the results of the research showed that the extract of the medicinal plant Goon has a suitable anti-microbial effect against the bacteria causing oral and dental infections, and it was expressed as an alternative to the standard drugs chlorhexidine and nystatin.

Hydrogels are 3-Dimensional (3-D) polymers that are water-insoluble. The functional groups in Hydrogels lead to water absorption and swell. In the Interpenetrating polymer network (I.P.N), polyvinyl sulfonic acid P(VSA) is imprisoned in the cross-linked polyvinyl pyrrolidone (PVP) because of the higher Maxwell energy of PVP rather than P(VSA).In this work, we prepared co-hydrogels by free radical polymerization method using the two monomers PVP and PVSA. The azobisisobutyronitrile (AIBN) as an initiator and N,N-methylen-e-bisacrylamide as a cross-linker agent was used at 65ċ for five hours and 45 minutes. We prepared co-hydrogels in 1:1,1:0.5,and 1:0.25 mole ratios on feed composition. Therefore, we obtained amphiphilic hydrogels to study the complexation behavior between the two cationic and anionic monomers. Uv-Spectrometry was performed. For the first time, the structural properties were identified by FT-IR. We investigated the swelling properties of synthesized co-hydrogels (Amphiphilite hydrogels) at different temperatures. The optimum temperature for the synthesized co-hydrogels was obtained.