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81.
Microchimica Acta - Graphene oxide nanosheets were modified with magnetite nanoparticles, and a hyperbranched polyamidoamine dendrimer was then covalently attached to their surface. The resulting... 相似文献
82.
Soleyman Hosseinzadeh Shahryar Pashaei Younes Saadat Zahra Khodaparast Roshan Javanifar Masoud Mohamadpour Alireza Hosseinzadeh 《Polymer Science Series B》2017,59(5):544-550
Cross-linked polystyrene (PS) particles having red blood corpuscle (RBC)-like shape were synthesized by one-pot dispersion polymerization of styrene with ethanol/water mixture and ethylene glycol dimethacrylate (EGDMA) as the reaction medium and cross-linker, respectively. Monitoring of the reaction showed that RBC-like shape forms due to asymmetric shrinkage of a cross-linked network during the phase separation. In addition, three dimensional phase diagram was generated based on the yielded data that showed that the formation of such unique shape extremely depends on the polarity of the medium and injection time of the cross-linker. In situ synthesis of RBC-like particles, as promising biomaterials in targeted drug delivery and a model for the understanding of the cell behavior, via such fast and high solid content approach makes it to be conducive to subsequent scale up, i.e. potential commercial adoption. 相似文献
83.
84.
Rahim Hosseinzadeh‐Khanmiri Yaser Kamel Zahra Keshvari Ahmad Mobaraki Gholam Hossein Shahverdizadeh Esmail Vessally Mirzaagha Babazadeh 《应用有机金属化学》2018,32(9)
In this research, preparation of the magnetic nanoparticle, coating by a silica shell using (3‐aminopropyl) triethoxysilane and synthesis of a novel sulfonic acid‐substituted imidazolium‐based ionic liquid onto the surface of these particles via a multi‐component reaction, is described. The functionalized nanoparticles was loaded by Ni nanoparticles and characterized by means of techniques such as XRD, FTIR, SEM, EDX, TEM, TGA and ICP‐OES. The nanostructures have spherical shapes that ranged in size from 80 to 100 nm. The catalytic activity of these nanoparticles was tested in aerobic oxidation of primary alcohols that showed good performance in the wide range of primary alcohols in water at mild reaction conditions. As a second step of this work, the tandem oxidative synthesis of alkylacrylonitriles and bisindolylmethanes were investigated using primary alcohols under oxidation conditions. This catalyst system can be recovered using external magnet and reused for five consecutive cycles without significantly less of its activity. 相似文献
85.
Mahmoud Roushani Zahra Saedi Fatemeh Hamdi Hamid Reza Rajabi 《Journal of the Iranian Chemical Society》2018,15(10):2241-2249
In this study, a new Cr(III)-imprinted polymer (Cr(III)-IIP) is prepared from CrCl3·6H2O, methacrylic acid functional monomer, ethyleneglycoldimethacrylate cross-linking agent, 2,2?-azobisisobutyronitrile radical initiator and 2,2-(azanediylbis (ethane-2,1-diyl))bis(isoindoline-1,3-dione) ligand. To obtain the maximum adsorption capacity, the optimum condition was studied through pH, type and concentration of eluent, IIP weight, sample volume as well as the adsorption and desorption times. The Cr(III) ion content was determined via flame atomic absorption spectrometer. In optimum conditions, the adsorption capacity of the IIP for Cr(III) was obtained to be 74.65 mg g?1, using 50 mg of IIP and the initial pH solution of 3.0. Both the adsorption and desorption times for quantitative analyses of Cr(III) ions were 15 and 5 min; respectively. After elution of the adsorbed ions by 3 mL of 4 mol L?1 HNO3 aqueous solution, the established IIP-based SPE procedure provides a reasonable pre-concentration factor of 100. The IIP-based pre-concentration method provides a low detection limit of 1.7 µg L?1 with good repeatability (RSD?=?3.22%). Reusability studies confirmed that synthesis IIP is reusable and recoverable up to six cycles. According to the selectivity experiments, it was concluded that the prepared sorbent possesses more affinity toward Cr(III) ions than other ions such as Al3+, Pb2+, Cu2+, Mn2+, Fe2+, Zn2+, and Ni2+ ions. To evaluate the potential applicability of the proposed separation method, the pre-concentration and determination of trace amounts of Cr(III) were performed successfully in food samples with complex matrices, a bestial sample (i.e. cow liver) and an herbal product (i.e., broccoli) as real samples. 相似文献
86.
Cu(II) immobilized on mesoporous organosilica nanoparticles (Cu2+@MSNs‐(CO2?)2) has been synthesized, as a inorganic–organic nanohybrid catalyst, through a post‐grafting approach. Its characterization is carried out by Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy dispersive X‐ray (EDX), Thermogravimetric/differential thermal analyses (TGA‐DTA), and Nitrogen adsorption–desorption analysis. Cu2+@MSNs‐(CO2?)2 exhibits high catalytic activity in the Biginelli reaction for the synthesis of a diverse range of 3, 4‐dihydropyrimidin‐2(1H)‐ones, under mild conditions. The anchored Cu(II) could not leach out from the surface of the mesoporous catalyst during the reaction and it has been reused several times without appreciable loss in its catalytic activity. 相似文献
87.
Zahra Moulana Mousa Ghaemi Soudabeh Qasemi Khadijeh Ghassemi Mohammad R. Hasanjani Roushan 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(1):30-39
There are many different strategies to decrease the incidence of infection of medical device and food related containers. One way to prevent infection is by modifying the polymers used in making the devices and containers. Incorporation of antimicrobial agents in the bulk material or in formulations of medical devices production has been considered a viable alternative for systemic application of antibiotics. In this article, preparation of a series of triazole containing polymers, poly(triazole-amide-imide)s (PTAI)s and poly(triazole-amide) (PTA)s, and their monomers are reported. These polymers were readily soluble in a variety of organic solvents, showed significant thermal properties and also viscosities in the range of 0.55–0.66 dL/g. They have been tested against a range of Gram-positive and Gram-negative pathogens. The results indicated that these novel polymers containing triazole moiety in their repeating units can effectively control Gram-positive and negative pathogens and their physic-chemical properties besides their antibacterial characteristics make them unique candidate for using in the manufacturing of the medical devices. 相似文献
88.
Hosseini Seyed Ghorban Khodadadipoor Zahra Mahyari Mojtaba Zinab Javad Mohebbi 《Journal of Thermal Analysis and Calorimetry》2019,135(2):963-979
Journal of Thermal Analysis and Calorimetry - The present study reports numerical simulations of water-based Al2O3 nanofluid flowing in a 2D channel with a heated wall-mounted obstacle. The... 相似文献
89.
A novel heterogeneous magnetic palladium nano‐biocatalyst was designed by utilizing Irish moss, a family of sulfated polysaccharides extracted from algae, as a natural biopolymer. This magnetic Irish moss decorated with palladium (Pd–Fe3O4@IM) to form a biomagnetic catalytic system was synthesized and well characterized by FT–IR analysis, X‐ray powder diffraction, field emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, atomic absorption spectroscopy and transmission electron microscopy. The catalyst was stable to air and moisture and displayed high catalytic activity in ligand‐free Suzuki–Miyaura cross‐coupling reactions conducted under green chemistry reaction conditions. The aromatic ketones are produced by the cross‐coupling reaction between acid chlorides and aryl boronic acid derivatives in high yields. 相似文献
90.
Emulsion‐based coatings and adhesives are in growing demand due to an increased awareness of health and safety issues arising from solvent‐based polymer manufacturing processes. However, emulsion‐based techniques often require additional development to achieve equal or better application performance compared to solvent‐based processes. The inclusion of nanoparticles in emulsion‐based coatings and adhesives can be considered as a promising means to enhance performance. This paper reviews the current progress on the synthesis of emulsion‐based nanocomposites for coating and adhesive applications and addresses the principles and techniques for nanoparticle dispersions and their inclusion into polymer latexes. The effects of nanoparticle shape and size on the enhancement of nanocomposite properties are also highlighted. Among the reinforcing nanoparticles such as nanoclays, carbon nanotubes, and cellulose nanocrystals (CNCs), CNCs are promising due to their abundance, nontoxicity, and accessible surface hydroxyl groups, which facilitate their compatibility with polymer latexes via physical and chemical treatments. 相似文献