NANO WORLD
Year:2024 | Volume:20 | Issue:76|Papers Count:7

Carbon is one of the very special and key elements with unique and miraculous properties in Mendeleev's periodic table. This particular element has different and attractive allotropes due to its high reactivity. Among all the different allotropes of carbon, diamond and diamond-like carbon, there are two special allotropes, the first one is found naturally and the second one is produced in a laboratory. These two allotropes are very similar in terms of characteristics and in some cases they have different points, each of which is used in different industries in its own way. There are key parameters for the production of each of these allotropes. Choosing the type of substrate, the type and percentage of reactive gases, the way of preparation before, after and also during the growth in the sample has a direct effect on the production and purity of diamond and diamond like carbon. In this article, the introduction of these two allotropes and the effective parameters in growth, and its advantages and disadvantages have been discussed.

In this study, a review of the performance of cation exchange membranes based on the nano-material additive graphene oxide (GO) used in desalination processes was carried out. Understanding the physicochemical properties of GO has a significant impact on understanding the physicochemical and electrochemical characteristics of the prepared membranes, as well as the mechanism governing the desalination process through the cation exchange groups. GO, due to the high-level number of oxygen-containing functional groups on its edges and sheets, can be easily functionalized with cation exchange groups such as (SO3H, -COOH, -PO3H2). GO has numerous applications in various fields such as gas separation, water purification, ionic dialysis, food processing, drug manufacturing, energy storage, and water desalination processes. While sulfonated GO has been widely synthesized and used for cation exchange applications in membranes, a limited number of studies have reported the use of phosphorus-containing cation exchange groups in the GO structure. Recent studies have shown that ion exchange membranes based on GO containing -PO3H2 groups can provide higher hydrophilicity. higher ion permeability (>98%) and permselectivity (>97%)، and better chemical and mechanical stability compared to those with sulfonic groups. Additionally, functionalizing GO with phosphorus-containing groups can provide better pH stability of the membranes compared to -SO3H and -COOH groups. This review article discusses the importance, role, and performance of GO structures functionalized with sulfonic and phosphorus groups for application in cation exchange membranes for desalination.

abstractLaser wear shows the exciting phenomenon of laser interaction with matter. The production of nanoparticles in the laser abrasion process is highly dependent on the properties of the material and laser parameters. One of the methods of producing nanoparticles is using a pulsed laser to separate the mass from the sample. Nanoparticles have special properties compared to the mass of matter and even micron dimensions. For this reason, the use of nanoparticles has been used in most technologies. In this article, we will first discuss how the laser interacts with the material, and then we will examine the effective parameters for better laser wear. After that, the main mechanisms of nanoparticle production and their dependence on different laser parameters, as well as the mechanisms of particle separation from the target, have been discussed. At the end, the effect of different laser parameters on the size and distribution of several samples of nanoparticles has been discussed, along with its corresponding graphs.

Pure hydroxyapatite nanocomposites with different amount of magnesium additive were synthesized using a simple sol-gel method. For this purpose, the initial gel was obtained by the chemical reaction of calcium, magnesium, and phosphorus-related precursors, and after remaining for 48 h at room temperature, it was dried for 24 h at 120˚C in an electric furnace. Finally, to remove the organic materials and volatiles, this product was placed at 600˚C for 3 h. This way, six samples with molar percentages of 0, 2, 4, 6, 8, and 10 of magnesium were prepared. To investigate the effect of magnesium amount on the nanocomposite properties, X-ray diffraction pattern (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) images were used, and also, compressive strength testing was performed. The results confirmed the successful synthesis of hydroxyapatite nanocomposites and showed that with increasing magnesium content, the crystal size decreases. Moreover, pure hydroxyapatite has a needle-like and plate-like microstructure, while in hydroxyapatite substituted with 4% magnesium, only needle-like structure is observable. In addition, in hydroxyapatite substituted with 10% magnesium, only plate-like structure is visible. Finally, the sample substituted with 4% magnesium showed the highest compressive strength, and the sample substituted with 10% magnesium ranked as the second one.

AbstractNanoparticles can be used for cancer diagnosis and treatment, however, their delivery to tumors is challenging. One of the main problems is the lack of understanding of the storage mechanisms of nanoparticles in solid tumors. To solve this problem, two mechanisms of producing nanoparticles to solid tumors and their effect on nanoparticles for cancer applications have been investigated. One of these proposed mechanisms is the effect of permeation and retention (EPR), which states that nanoparticles are inefficient to tumors through endothelial tissue gaps. To solve this problem, an alternative mechanism called the active transport and maintenance effect (ATR) has also been proposed; which suggests the entry, retention and active exit of nanoparticles as the basic mechanisms of nanoparticle production in solid tumors. This mechanism can improve the production of nanoparticles to tumors and increase the efficiency of cancer treatment. This article provides an overview that the mechanisms of delivery of nanoparticles to solid tumors are critical for the advancement of nanomedicine in determining ways to cure cancer.

The threat of antibiotic drugs to humans and the environment has been noticed more than ever. Ciprofloxacin (Cip), as a strong quinolone antibiotic, is widely used in various treatments. This drug is among the fluoroquinolone drugs detected in surface water more often, which will bring health risks to animals and humans. In this study, a bimetallic metal-organic framework fluorescence nanosensor with d-f orbitals of intermediate metal and lanthanide with the molecular formula {[EuZn(pzdc)2(H2O)3]·H2O}n (MOF-I) (H2pzdc = 2,3-pyrazine dicarboxylic acid) was synthesized using the biocompatible method of ultrasonic waves to identify Cip antibiotic. Structure and characteristics of MOF-I nanosensor by powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR), thermal analysis (TGA), photoluminescence (PL) spectra, ultraviolet-visible (UV) spectrophotometry -Vis) and scanning electron microscope (SEM). According to the red emission of MOF-I caused by 4f-5d transitions of central metal Eu3+ corresponding to energy levels 5D0→7FJ (J=0→4), it was investigated to identify Cip. The experimental results show that the red fluorescence emission of the MOF-I nanosensor is turned off in the presence of the Cip molecule and the gradual increase in its concentration, using the internal filter effect (IFE) mechanism. The MOF-I nanosensor is associated with fast, stable, selectable response and high sensitivity in determining Cip. Considering the good linear correlation of the fluorescence response of MOF-I nanosensor to Cip concentration in the range of 1 to 40 μM and the lowest LOD equal to 0.32 μM, it indicates the reliability and applicability of the synthetic nanosensor in the detection of Cip antibiotic. .

Zinc oxide nanomaterials are non-toxic, environmentally friendly, biodegradable, low-cost and easily available. This nanomaterial has special physical, chemical, optical and electrical properties. It also has various synthesis methods that can modify the produced nanoparticles with organic, polymeric and metallic materials according to the required application and purpose and improve their properties and compatibility and use them for various applications including medicine and engineering. In addition, it has different structures or shapes on the nano scale and they can be produced in one, two or three dimensions in nano form. All these features have made these nanomaterials to be used in improving the properties of various materials and applications such as plastic and rubber materials, food and health, pharmaceutical and medical, paint, construction and many other applications. Therefore, this article briefly talks about the engineering or non-engineering applications of zinc oxide nanoparticles, such as applications in polymer industries, paper, sensors, making catalysts, absorbing heavy metals and oil industry.