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111.
Ahmad Reza Bagheri Mehrorang Ghaedi Kheibar Dashtian Shaaker Hajati Ali Akbar Bazrafshan 《应用有机金属化学》2018,32(1)
TiO2 nanoparticles deposited on activated carbon (TiO2–NP–AC) was prepared and characterized by XRD and SEM analysis. Subsequently, simultaneous ultrasound‐assisted adsorption of Cu2+ and Cr3+ ions onto TiO2‐NPs‐AC after complexation via eriochrome cyanine R (ECR) has been investigated with UV–Vis and FAA spectrophotometer. Spectra overlapping of the ECR‐Cu and ECR‐Cr complex was resolve by derivative spectrophotometric technique. The effects of various parameters such as initial Cu2+ (A) and Cr3+ (B) ions concentrations, TiO2‐NPs‐AC mass (C), sonication time (D) and pH (E) on the removal percentage were investigated and optimized by central composite design (CCD). The optimize conditions were set as: 4.21 min, 0.019 mg, 20.02 and 13.22 mg L?1 and 6.63 for sonication time, TiO2–NP–AC mass, initial Cr3+ and Cu2+ ions concentration and pH, respectively. The experimental equilibrium data fitting to Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models show that the Langmuir model is a good and suitable model for evaluation and the actual behavior of adsorption process and maximum adsorption capacity of 105.26 and 93.46 mg g?1 were obtained for Cu2+ and Cr3+ ions, respectively. Kinetic evaluation of experimental data showed that the adsorption processes followed well pseudo second order and intraparticle diffusion models. 相似文献
112.
Abasabadi Reza Khaleghi Khodadadi Abbas Ali Mortazavi Yadollah 《Research on Chemical Intermediates》2021,47(4):1429-1446
Research on Chemical Intermediates - The importance of electronic and chemical properties of nitrogen-doped reduced graphene oxide (NRGO) has attracted more attention in recent years. Various... 相似文献
113.
Maryam S. Sadeghi Mohammad Reza Moghbeli William A. Goddard III 《Journal of polymer science. Part A, Polymer chemistry》2021,59(7):614-626
We followed the self-assembly of high-molecular weight MePEG- b -PCL (poly(methyl ethylene glycol)-block-poly(ε-caprolactone)) diblock and MePEG- b -PBO- b -PCL (poly(methyl ethylene glycol)-block-poly(1,2-butylene oxide)-block-poly(ε-caprolactone)) into micelles using molecular dynamics simulation with a coarse grain (CG) force field based on quantum mechanics (CGq FF). The triblock polymer included a short poly(1,2-butylene oxide) (PBO) at the hydrophilic-hydrophobic interface of these systems. Keeping the hydrophilic length fixed (MePEG45), we considered 250 chains in which the hydrophobic length changed from PCL44 or PBO6- b -PCL43 to PCL62 or PBO9- b -PCL61. The polymers were solvated in explicit water for 2 μs of simulations at 310.15 K. We found that the longer diblock system undergoes a morphological transition from an intermediate rod-like micelle to a prolate-sphere, while the micelle formed from the longer triblock system is a stable rod-like micelle. The two shorter diblock and triblock systems show similar self-assembly processes, both resulting in slightly prolate-spheres. The dynamics of the self-assembly is quantified in terms of chain radius of gyration, shape anisotropy, and hydration of the micelle cores. The final micelle structures are analyzed in terms of the local density components. We conclude that the CG model accurately describes the molecular mechanisms of self-assembly and the equilibrium micellar structures of hydrophilic and hydrophobic chains, including the quantity of solvent trapped inside the micellar core. 相似文献
114.
Hashemi Karouei Seyed Hossein Ajarostaghi Seyed Soheil Mousavi Gorji-Bandpy Mofid Hosseini Fard Seyed Reza 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1455-1466
Journal of Thermal Analysis and Calorimetry - In the present study, the effect of inserting an innovative curved turbulator and utilizing two types of hybrid nanofluids on thermal performance in a... 相似文献
115.
This article aims to provide a survey of biological applications of Schiff base macrocycles and their metal complexes, with emphasis given to the synthesis of the compounds and to their uses as antibacterial and antifungal agents. The literature on the subject, published during the 2005–2019 period, is shortly reviewed. This is an informed report collecting information on the addressed topic in a concise systematic way, and can be expected to be useful as a fast literature catalogue for researchers working on this and related domains. 相似文献
116.
Bahareh Heidari Majid M. Heravi Mohammad Reza Nabid Roya Sedghi Seyyed Emad Hooshmand 《应用有机金属化学》2019,33(1)
A novel nanocatalyst was designed and prepared. Initially, the surface of magnetic graphene oxide (M‐GO) was modified using thionyl chloride, tris(hydroxymethyl)aminomethane and acryloyl chloride as linkers which provide reactive C═C bonds for the polymerization of vinylic monomers. Separately, β‐cyclodextrin (β‐CD) was treated with acryloyl chloride to provide a modified β‐CD. Then, in the presence methylenebisacrylamide as a cross‐linker, monomers of modified β‐CD and acrylamide were polymerized on the surface of the pre‐prepared M‐GO. Finally, palladium acetate and sodium borohydride were added to this composite to afford supported palladium nanoparticles. This fabricated nanocomposite was fully characterized using various techniques. The efficiency of this easily separable and reusable heterogeneous catalyst was successfully examined in Suzuki–Miyaura cross‐coupling reactions of aryl halides and boronic acid as well as in modified Suzuki–Miyaura cross‐coupling reactions of N‐acylsuccinimides and boronic acid in green media. The results showed that the nanocatalyst was efficient in coupling reactions for direct formation of the corresponding biphenyl as well as benzophenone derivatives in green media based on bio‐based solvents. In addition, the nanocatalyst was easily separable, using an external magnet, and could be reused several times without significant loss of activity under the optimum reaction conditions. 相似文献
117.
Amir Shakouri Reza Parvan Nasim Adljouy Jalal Abdolalizadeh 《Biomedical chromatography : BMC》2020,34(1):e4709
Hyaluronidase (Hyal) can be employed to accomplish a diversity of complications related to hyaluronic acid (HA). Hyal contains some classes of catalysts that cleave HA. This enzyme is detected in several human tissues as well as in animal venoms, pathogenic organisms and cancers. Destructive cancer cells regularly increase the CD44 receptor existing in a cell membrane. This receptor acts as an exact receptor for HA, and HA is recognized to motivate the migration, spread, attack and metastasis of cancer cells. Nearly all of the methods used to purify Hyal are highly costly and not proper for industrial applications. This survey aims to review different methods of Hyal purification, which acts as an anticancer agent by degrading HA in tissues and thus inhibiting the CD44–HA interaction. Hyal can be successfully employed in the management of cancer, which is associated with HA–CD44. This review has described different methods for Hyal purification to prepare an origin to develop a novel purification technique for this highly appreciated protein. Using multiple columns is not applicable for the purification of Hyal and thus cannot be used at the industrial level. It is better to use affinity chromatography of anti-Hyal for Hyal with one-step purification. 相似文献
118.
Structural Chemistry - Density functional theory (DFT) calculations at B3LYP/6-31+G(d) level were employed to investigate the influence of the non-metal encapsulation of the second row of the... 相似文献
119.
In this research, the main emphasis has been focused on the preparation of a novel Fe3O4-supported propane-1-sulfonic acid-grafted graphene oxide quantum dots (Fe3O4@GOQD-O-(propane-1-sulfonic acid)) that it was readily synthesized via a five-step procedure as a hitherto unreported magnetic nanocatalyst. This newly prepared Fe3O4@GOQD-O-(propane-1-sulfonic acid) nanocomposite was structurally well-established by different analytical techniques including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray (EDX), thermal gravimetric analysis (TGA), field emission gun-scanning electron microscope (FESEM), high-resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer (VSM) analyses. The high catalytic performance of this nanocomposite was exhibited in one-pot synthesis of dihydropyrano[2,3-c]pyrazole and 4H-chromene derivatives under mild conditions. Low reaction times, excellent yields of the products, benignity of the catalyst, easy reaction work-up and magnetic recyclability of the catalyst are the main advantages of the present protocol. Also, our research indicated that the Fe3O4@GOQD-O-(propane-1-sulfonic acid) could be reused up to five times without considerable loss of catalytic activity. 相似文献
120.
In this study, a novel Cu-immobilized ionic liquid (IL)was designed, characterized, and employed as both promoter and solvent in the synthesis of some dihydropyrano[2,3-c]pyrazoles. The synthesized ionic liquid was characterized by 1H NMR, 13C NMR, FTIR, ICP and EDX analysis and showed high catalytic activity to proceed the synthesis of bioactive dihydropyrano[2,3-c]pyrazole derivatives. This method has the advantage of using the IL as a green medium for the synthesize of the products in high to excellent yields within short reaction times. 相似文献