نشریه کاربرد شیمی در محیط زیست
پیاپی 55 (پاییز 1402)

One of the most common problems is water quality management of seas and reservoirs around the world. About 30-40% of lakes and reservoirs worldwide are affected by abnormally high nutrients. Eutrophic phenomena are caused by an excess of nutrients in an aquatic system, especially by nitrogen and phosphorus, especially in lakes, estuaries and slow streams. Due to the excessive consumption of fertilizers and the discharge of untreated urban and industrial wastewater into water sources, the extent of eutrophication processes has increased significantly since the middle of the last century. One of the obvious signs of eutrophication is dense algal blooms, which cause high turbidity in water systems, decrease of oxygen and increase of hypoxia conditions in the inner parts of water bodies due to the sediments. In addition, extensive development of blue-green cyanobacteria, reduction of biodiversity, formation of hydrogen sulfide, increase in fish mortality, unpleasant odor, and increased phytoplankton and other aquatic plants, are other effects of eutrophication on the ecosystem. The main nutrients of interest are nitrogen and phosphorus, both of which are essential for algal growth, but the role of phosphorus is more critical because many cyanobacteria can obtain the nitrogen, they need from atmospheric nitrogen through nitrogen fixation. Therefore, most of the eutrophication control measures are directed towards reducing phosphorus. The purpose of this study is to investigate the types, causes, stages and factors, and finally solutions to control, modify and prevent the process of eutrophication.

Nature is full of examples of smart or stimuli-responsive materials. Leaves of the Dionaea muscipula (venus flytrap) can capture insects, leaflets of Codariocalyx motorius and Helianthus annuus can rotate under exposure to sunlight, leaves of Mimosa pudica can collapse when shaken or touched and Chamaeleonidae or Octopoda change their color depending on the environmental condition or situation. These natural phenomena have attracted the attention of researchers for a long time, and various attempts have been made to imitate this behavior using synthetic materials. In this sense, the synthesis, properties, and application of stimuli-responsive polymers have become one of the most important research lines of polymer science. Smart polymers or stimuli-responsive polymers undergo large reversible changes, either physical or chemical, in their properties as a consequence of small environmental variations. They can respond to a single stimulus or multiple stimuli such as temperature, pH, electric or magnetic field, light intensity, biological molecules, etc., that induce macroscopic responses in the material, such as swelling/collapse or solution-to-gel transitions, depending on the physical state of the chains. The addition of nanofillers can enhance the performance of stimuli-responsive polymers (e.g., shape stabilization, shape recovery, self-healing ability) due to high specific surface area, nucleation effects, reinforcement effects, and intrinsic functions (e.g., thermal conductivity, electrical conductivity). This research work tries to provide a wide review of physical methods of nanomaterial and smart polymer nanocomposite preparation.

In this study, 3-Picrylamino-1,2,4-triazole interaction with carbon nanocone dots was evaluated by infrared (IR), natural bond orbital (NBO) and frontier molecular orbital (FMO) computations. The negative values of adsorption energy, enthalpy changes, Gibbs free energy variations showed 3-Picrylamino-1,2,4-triazole adsorption on the surface of carbon nanocone is exothermic, spontaneous and experimentally feasible. Structural parameters including the energy of HOMO and LUMO orbitals, bandgap, electrophilicity, chemical potential, chemical hardness, density and zero-point energy were also calculated and discussed. The remarkable decrease in bandgap after the 3-Picrylamino-1,2,4-triazole adsorption on the surface of carbon nanocone demonstrated that the electrochemical conductivity and electrocatalytic properties increased after adsorbate interaction with the adsorbent and carbon nanocone can be used for construction of new electrochemical sensor in order to 3-Picrylamino-1,2,4-triazole detection and quantitation. In addition, this phenomenon showed 3-Picrylamino-1,2,4-triazole complexes with carbon nanocone can be a more powerful energetic substance than the pure 3-Picrylamino-1,2,4-triazole molecule without the nanostructure.

The thyroid gland is one of the most important glands in the body that regulates the body's energy metabolism. This gland has a butterfly-like shape and is located in front of the trachea. Due to the increasing prevalence of thyroid diseases and the lack of appropriate treatment for this disease, the present study aimed to investigate the effect of food powder (Made from grains) on changes in the concentration of T3, T4, TSH hormones in male rats. Lead acetate was performed. Materials.and

For this study, 30 Wistar rats were used. To induce the disease, lead acetate was used in combination with diet in mice and mice in treatment groups with concentrations of 125, 250 and 500 mg. They received food powder (Made from grains) per kilogram of body weight.

According to the results of T3, T4, TSH tests in the blood of the studied mice, it can be concluded that food powder (Made from grains) causes a relative return of T3, T4, TSH levels to normal. In the study of the interaction of the concentrations used in food powder (Made from grains), it was found that the concentration of 500 ml / kg has the most effective therapeutic effect and the concentration of 125 ml / kg has the least effect against hypothyroidism.

According to the results of this study, it can be stated that food powder (Made from grains) is a suitable therapeutic effect for the treatment of thyroid parameters abnormalities.

One of the major problems of today's mankind is the pollution of water sources, among the sources of water pollution are dyes, which are among the most dangerous groups of chemical compounds found. Green malachite produces toxic by products due to various reactions, and due to its high toxicity, environment are very important. One of the best ways to remove these materials is to use surface absorption process using nano technology. Iron nanoparticles have such characteristics due to their abundance, cheapness, non-toxicity, fast reaction and ability and high efficiency in the decomposition of pollutants and removal of Green malachite from polluted waters. In this research, the synthesis of nanomagnet coated with dithiocarbamate and its performance evaluation in removing Green malachite from aqueous solutions was carried out. The characteristics and structure of nanomagnet with dithiocarbamate coating were investigated by FTIR, XRD, SEM. The experimental factors including amount of adsorbent, amount of pollutant, contact time and pH were studied in discontinuous system. Taguchi method was used to determine the optimal conditions for each of these parameters. The results showed that the most effect is the amount of adsorbent and the least effect is related to contact time.

Carbon nanotubes (CNTs) represent one of the most unique inventions in the field of nanotechnology. They have unique properties and characteristics. They have unique properties and characteristics. Carbon nanotubes have strong bonds between their atoms, and for this reason, they show great resistance and strength against tensile forces. But interatomic bonds in nanotubes, in addition to creating high strength, enable easy plasticity and even twisting in them. While steel only has resistance against tensile forces and does not have the necessary flexibility for twisting. The methods used to produce carbon nanotubes include laser ablation, electric arc discharge, chemical vapor deposition, plasma enhanced chemical vapor deposition, pulsed laser deposition, use of low-frequency ultrasound, bulk polymer heating, and bulk sputtering. CNTs have very good mechanical and thermal properties that strongly depend on their structure. Functionalized magnetic CNTs are involved in magnetic force microscopy used in biomedicine. The liquid and plastic limit of kaolinite can be increased by adding CNT to it. In the field of medicine, CNTs have many applications, including gene transfer to cells, cancer therapy, drug delivery, and tissue regeneration. Their antioxidant nature also allows them to be used in cosmetic and dermatological products. The most important property of nanotubes is their electrical conductivity, which varies depending on the arrangement of atoms. applications and their properties can be improved by making their composites with metals. Such metals may be introduced into the core of carbon nanotubes by various methods including solid state reaction, arc discharge method and electrochemical techniques. The amount of hydrogen gas absorbed in CNTs varies between 0.4 and 67% by mass.