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21.
Dr. Guanzhao Wu Yangxue Liu Hossein Rouh Liulei Ma Yao Tang Sai Zhang Peng Zhou Jia-Ying Wang Shengzhou Jin Dr. Daniel Unruh Dr. Kazimierz Surowiec Prof. Dr. Yanzhang Ma Prof. Dr. Guigen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(30):8013-8020
The first asymmetric catalytic approach to multilayer 3D chirality has been achieved by using Suzuki-Miyaura cross-couplings. New chiral catalysts were designed and screened under various catalytic systems that proved chiral amide-phosphines to be more efficient ligands than other candidates. The multilayer 3D framework was unambiguously determined by X-ray structural analysis showing a parallel pattern of three layers consisting of top, middle and bottom aromatic rings. The X-ray structure of a catalyst complex, dichloride complex of Pd-phosphine amide, was obtained revealing an interesting asymmetric environment nearby the Pd metal center. Three rings of multilayer 3D products can be readily changed by varying aromatic ring-anchored starting materials. The resulting multilayer products displayed strong luminescence under UV irradiation and strong aggregation-induced emission (AIE). In the future, this work would benefit not only the field of asymmetric synthesis but also materials science, in particular polarized organic electronics, optoelectronics and photovoltaics. 相似文献
22.
Cellulose - The electrical conductivity of cotton fabrics was enhanced using an in situ synthesis of graphene or polymerization of conductive polymer. The impact of conductive materials... 相似文献
23.
In this paper, a decentralized adaptive control scheme for multi-robot coverage is proposed. This control method is designed based on centroidal Voronoi configuration integrated with robust adaptive fuzzy control techniques. We consider simple single integrator mobile robots used for covering dynamical environments, where an adaptive fuzzy logic system is used to approximate the unknown parts of control law. A robust coverage criterion is used to attenuate the adaptive fuzzy approximation error and measurement noises to a prescribed level. Therefore, the robots motion is forced to obey solutions of a coverage optimization problem. The advantages of the proposed controller can be listed as robustness to external disturbances, computation uncertainties, and measurement noises, while applicability on dynamical environments. A Lyapunov-function based proof is given of robust stability, i.e. convergence to the optimal positions with bounded error. Finally, simulation results are demonstrated for a swarm coverage problem simultaneous with tracking mobile intruders. 相似文献
24.
Seyedeh Hoda Jazayeri Amir Amiri-Yekta Salahadin Bahrami Hamid Gourabi Mohammad Hossein Sanati Mohammad Reza Khorramizadeh 《Applied biochemistry and biotechnology》2018,185(4):986-1003
The rapid growth of global biopharmaceutical market in the recent years has been a good indication of its significance in biotechnology industry. During a long period of time in recombinant protein production from 1980s, optimizations in both upstream and downstream processes were launched. In this regard, one of the most promising strategies is expression vector engineering technology based on incorporation of DNA opening elements found in the chromatin border regions of vectors as well as targeting gene integration. Along with these approaches, cell line engineering has revealed convenient outcomes in isolating high-producing clones. According to the fact that more than 50% of the approved therapeutic proteins is being manufactured in mammalian cell lines, in this review, we focus on several approaches and developments in vector and cell line engineering technologies in mammalian cell culture. 相似文献
25.
Soap-free emulsion polymerization (SFEP) of methyl methacrylate, butyl acrylate was conducted in water/methanol media with sodium salts of four different acidic comonomers, namely styrene sulfonic acid (NaSS), 2-acrylamide-2-methyl-1-propane sulfonic acid (NaAmps), acrylic acid (NaAA), and itaconic acid (Na2ita). It was found that the introduction of methanol as co-solvent (35 wt%) to the medium greatly decreases the amount of water-soluble polyelectrolyte in the cases NaAA and Na2ita while it does not make difference for NaSS and NaAmps. Having employed the concept of conductance dependency to the ion mobility, the onset concentration in which soluble chains were formed was detected. The addition of sulfonic-based comonomers (NaSS and NaAmps), first decreased particle size and then led to predomination of solution polymerization over SFEP. On the contrary, the incorporation of carboxylic-based comonomers (NaAA and Na2ita) led to increase in particle size. Moreover, the particle size results were in good qualitative agreement with the classical Smith–Ewart theory. 相似文献
26.
Majid M. Heravi Hossein A. Oskooie Ladan Sangsefidi Mitra Ghassemzadeh Koroush Tabar-Hydar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2843-2846
Oxidative deprotection of tetrahydropyranyl ethers (THP ethers) using chromium trioxide supported onto zeolite under microwave irradiation in solvent free condition is described. 相似文献
27.
A facile, one-pot synthesis of new phenanthridine derivatives by a three-component reaction between phenantridine, dialkyl acetylenedicarboxylates(DAADs), and aromatic aldehydes is described. The reaction is characterized by mild conditions, high selectivity, and tolerance to various functional groups. 相似文献
28.
Green and one‐pot surface coating of iron oxide magnetic nanoparticles with natural amino acids and biocompatibility investigation 下载免费PDF全文
Hamed Nosrati Marziyeh Salehiabar Elahe Attari Soodabeh Davaran Hossein Danafar Hamidreza Kheiri Manjili 《应用有机金属化学》2018,32(2)
We report the synthesis of iron oxide magnetic nanoparticles (IONPs) coated with various natural amino acids (AAs) using a one‐pot reaction in an aqueous medium. Several AAs, which contained hydrophilic and hydrophobic groups, were selected to study their effects on size, morphology and toxicity of IONPs. Functionalized IONPs were characterized using X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning and transmission electron microscopies. Furthermore, vibrating sample magnetometry analysis shows these nanoparticles have excellent magnetic properties. Cellular toxicity of IONPs was also investigated on HFF2 cell lines. The AA‐coated IONPs are non‐toxic and biocompatible. Natural AA‐coated IONPs show a potential for their development in in vitro and in vivo biomedical fields due to their non‐toxicity, good ζ‐potential and related small size and narrow size distribution. 相似文献
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