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排序方式: 共有306条查询结果,搜索用时 34 毫秒
1.
Soltani Rad Mohammad Navid Behrouz Somayeh Mohammad-Javadi Mehdi Zarenezhad Elham 《Molecular diversity》2022,26(5):2503-2521
Molecular Diversity - The preparation, characterization and application of hydroxyapatite silica propyl bis aminoethoxy ethane cuprous complex (HASPBAEECC) as a novel hybrid nano-catalyst for... 相似文献
2.
Ali Pourjavadi Maryam Tavakolizadeh Seyed Hassan Hosseini Navid Rabiee Mojtaba Bagherzadeh 《Journal of polymer science. Part A, Polymer chemistry》2020,58(15):2062-2073
A number of synthetic hydrogels suffer from low mechanical strength. Despite of the recent advances in the fabrication of tough hydrogels, it is still a great challenge to simultaneously construct high stretchability, and self-adhesive and self-healing capability in a hydrogel. Herein, a new type of double network hydrogel was prepared based on irreversible cross-linking of polyacrylamide chains and Schiff-base reversible cross-linking between glycidyl methacrylate-grafted ethylenediamine and oxidized sodium alginate (OSA). The combination of both cross-linkings and their synergistic effect provided a novel hydrogel with high strength, stretchable, rapid self-healing, and self-adhesiveness to different material. Besides, the hydrogels with diverse OSA content could maintain their original shapes after loading–unloading tensile test. The resulting hydrogel has a great potential in various fields for supporting and load-bearing substance. 相似文献
3.
Ahmed F. Khanam Achiya Samylingam L. Aslfattahi Navid Saidur R. 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12669-12692
Journal of Thermal Analysis and Calorimetry - The present study numerically investigates the optimization of thermal performance in a dimpled channel using a promising genre of nanofluid which is... 相似文献
4.
Elnaz Marzi Khosrowshahi Behnaz Limuie Khosrowshahi Mir Ali Farajzadeh Abolghasem Jouyban Mustafa Tuzen Mohammad Reza Afshar Mogaddam Mahboob Nemati 《Biomedical chromatography : BMC》2022,36(7):e5371
A dispersive solid-phase extraction method based on a new sorbent has been performed on plasma and wastewater samples to determine metoprolol by high-performance liquid chromatography–tandem mass spectrometry. In this study, the analyte was adsorbed from the samples onto microcrystalline cellulose as a green and efficient sorbent and then eluted for use in the determination step. In the mass spectrometer, the analyte was detected in the positive mode and selectivity of the analysis was increased by sequential mass analysis through multiple reaction monitoring. All of the effective parameters in the extraction of metoprolol from plasma and wastewater were optimized. Under optimal conditions the method was linear in the ranges of 1–1,000 and 0.1–1,000 ng/ml in plasma and wastewater samples, respectively. The detection limits of the method were 0.30 and 0.03 ng/ml in plasma and wastewater samples, respectively. The data showed that the method provides low detection limit, wide linear range, good precision and high extraction recovery. Finally several plasma and wastewater samples were successfully analyzed using the method. The use of a small amount of a green and inexpensive sorbent and a low volume of plasma without the need for further pretreatment steps are the main advantages of the method. 相似文献
5.
Copper/Graphene/Clay Nanohybrid: A Highly Efficient Heterogeneous Nanocatalyst for the Synthesis of Novel 1,2,3‐Triazolyl Carboacyclic Nucleosides via ‘Click’ Huisgen 1,3‐Dipolar Cycloaddition 下载免费PDF全文
Mohammad Navid Soltani Rad Somayeh Behrouz S. Jafar Hoseini Hasan Nasrabadi Maryam Saberi Zare 《Helvetica chimica acta》2015,98(9):1210-1224
A very mild and highly efficient synthesis of some novel 1H‐1,2,3‐triazolyl carboacyclic nucleosides via a ‘Click’ Huisgen cycloaddition of N‐propargyl nucleobases and azido alcohols using Cu/aminoclay/reduced graphene oxide nanohybrid (Cu/AC/r‐GO nanohybrid) as nanocatalyst is described. The preparation and characterization of Cu/AC/r‐GO nanohybrid are discussed. This catalyst was characterized by X‐ray diffraction, FT‐IR, TEM, and energy‐dispersive analysis of X‐ray techniques. Cu/AC/r‐GO nanohybrid is a stable and highly efficient heterogeneous nanocatalyst that can be easily prepared, used, and restored from the reaction mixture by simple filtration, and reused for many consecutive trials without significant decrease in activity. 相似文献
6.
Light‐Driven Reversible Alignment Switching of Liquid Crystals Enabled by Azo Thiol Grafted Gold Nanoparticles 下载免费PDF全文
Dr. Chenming Xue Jie Xiang Hossein Nemati Dr. Hari Krishna Bisoyi Karla Gutierrez‐Cuevas Dr. Ling Wang Dr. Min Gao Shuang Zhou Prof. Deng‐ke Yang Prof. Oleg D. Lavrentovich Dr. Augustine Urbas Prof. Quan Li 《Chemphyschem》2015,16(9):1852-1856
Stimuli‐directed alignment control of liquid crystals (LCs) with desired molecular orientation is currently in the limelight for the development of smart functional materials and devices. Here, photoresponsive azo thiol (AzoSH) was grafted onto gold nanoparticles (GNPs). The resulting hybrid GNPs were able to homogeneously mix with a commercially available nematic LC host, as evidenced by Cryo‐TEM. Interestingly, the LC nanocomposites were found to undergo reversible alignment transition upon light irradiation as a consequence of the trans–cis photoisomerization of the azo groups on the GNP surface. LC molecules in either planar or bare glass cells were able to change their alignment to vertical upon UV irradiation, while the vertically aligned LC molecules returned to the planar or random orientation under visible irradiation. Neither the azo thiol molecules nor the unfunctionalized GNPs alone promoted the alignment of the LC molecules in the system upon light irradiation. The photoinduced vertical alignment without applied electric or magnetic field was very stable over time and with respect to temperature. Furthermore, an optically switchable device based on the photostimulated reversible alignment control of LCs was demonstrated. 相似文献
7.
Dan Yuan Sharda Yadav Hang T. Ta Hedieh Fallahi Hongjie An Navid Kashaninejad Chin Hong Ooi Nam-Trung Nguyen Jun Zhang 《Electrophoresis》2021,42(21-22):2230-2237
Microfluidic particle focusing has been a vital prerequisite step in sample preparation for downstream particle separation, counting, detection, or analysis, and has attracted broad applications in biomedical and chemical areas. Besides all the active and passive focusing methods in Newtonian fluids, particle focusing in viscoelastic fluids has been attracting increasing interest because of its advantages induced by intrinsic fluid property. However, to achieve a well-defined focusing position, there is a need to extend channel lengths when focusing micrometer-sized or sub-microsized particles, which would result in the size increase of the microfluidic devices. This work investigated the sheathless viscoelastic focusing of particles and cells in a zigzag microfluidic channel. Benefit from the zigzag structure of the channel, the channel length and the footprint of the device can be reduced without sacrificing the focusing performance. In this work, the viscoelastic focusing, including the focusing of 10 μm polystyrene particles, 5 μm polystyrene particles, 5 μm magnetic particles, white blood cells (WBCs), red blood cells (RBCs), and cancer cells, were all demonstrated. Moreover, magnetophoretic separation of magnetic and nonmagnetic particles after viscoelastic pre-focusing was shown. This focusing technique has the potential to be used in a range of biomedical applications. 相似文献
8.
A facile and efficient method for dehydration of aldoximes into nitriles using N-(p-toluenesulfonyl) imidazole (TsIm) is described. In this method, aldoximes were refluxed with TsIm in the presence of 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU) in dimethylformamide (DMF) to afford the corresponding nitriles in good yields. This methodology is highly efficient for various structurally diverse aldoximes including aromatic, heteroaromatic, and aliphatic oximes. A plausible mechanism for the conversion of aldoxime into nitriles using TsIm/DBU is explained. 相似文献
9.
Mohammad Navid Soltani Rad Ali Khalafi-Nezhad Somayeh Behrouz Zohreh Amini Marzieh Behrouz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1658-1671
A facile and highly efficient method for one-pot Beckmann rearrangement of ketoximes into N-substituted amides using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, ketoximes are refluxed with TsIm and Cs2CO3 in the presence of SiO2 as a recyclable catalyst in DMF affording the corresponding amides in high yields. This methodology is highly efficient and regioselective for various structurally diverse ketoximes including symmetrical and unsymmetrical as well as cyclic oximes. The results of quantum mechanical studies used to rationalize the experimental outcomes are discussed. 相似文献
10.
Mohammad Navid Soltani Rad Somayeh Behrouz Abdollah Movahedian Mohammad Mahdi Doroodmand Younes Ghasemi Sara Rasoul‐Amini Abdol‐Rasoul Ahmadi Gandomani Ramin Rezaie 《Helvetica chimica acta》2013,96(4):688-701
A facile and simple protocol for the 1,3‐dipolar cycloaddition of organic azides with terminal alkynes catalyzed by doped nano‐sized Cu2O on melamine? formaldehyde resin (nano‐Cu2O? MFR) as a new and convenient heterogeneous catalyst is described. In this method, ‘click’ cycloaddition of various structurally diverse β‐azido alcohols and alkynes in the presence of nano‐Cu2O? MFR in H2O/THF 1 : 2 furnished the corresponding 1,4‐disubstituted 1H‐1,2,3‐triazole adducts 1a – 1o in good to excellent yields at room temperature (Scheme and Table 3). The nano‐Cu2O? MFR was characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), inductively coupled plasma (ICP) analysis, and FT‐IR. The nano‐Cu2O? MFR could be easily recovered and recycled from the reaction mixture and reused for many consecutive trials without significant decrease in activity (Table 4). The in vitro antibacterial activities of all synthesized compounds were tested on several Gram‐positive and/or Gram‐negative bacteria (Table 5). The results demonstrate the promising antibacterial activity for some of the synthesized compounds. 相似文献