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941.
Nanocellulose (NC) materials have some unique properties, which make them attractive as organic or inorganic supports for catalytic applications. Nanocatalysts with diameters of less than 100 nm are difficult to separate from the reaction mixture, therefore, magnetic nanoparticles (MNPs) were used as catalysts to overcome this problem. Fe3O4@NCs/BF0.2 as a green, bio‐based, eco‐friendly, and recyclable catalyst was synthesized and characterized using fourier‐transform infrared spectroscopy (FT‐IR), vibrating sample magnetometer (VSM), X‐ray diffraction (XRD), X‐ray fluorescence (XRF), Brunauer–Emmett–Teller (BET), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and thermal gravimetric analysis (TGA) techniques. Fe3O4@NCs/BF0.2 was employed for the synthesis of 2,3‐dihydro‐1H‐perimidine derivatives via a reaction of 1,8‐diaminonaphthalene with various aldehydes at room temperature under solvent‐free conditions. The present procedure offers several advantages including a short reaction time, excellent yields, easy separation of catalyst, and environmental friendliness. 相似文献
942.
Structural Chemistry - Kinesin Eg5 plays an essential role in the early stages of mitosis, and it is an interesting drug target for the design of potent inhibitors. In this work, combined molecular... 相似文献
943.
ABSTRACTLipids and DNAs are two major building blocks of life. Interestingly, by chemically linking these two natural compounds together, synthetic lipid-DNA conjugates exhibit several attractive features for cell membrane studies. These lipid-DNA conjugates are amphiphilic macromolecules combining the cell membrane insertion capability of lipids with the properties of DNAs in precise hybridization and programmability. These supramolecular conjugates have demonstrated exciting applications from generating cell membrane nanopores to transmembrane cargo deliveries, and from analyzing cell membrane events to tissue engineering. In this review, we will discuss the design, structures, and biological applications of lipid-DNA conjugates, with an emphasis on their functions on live cell membranes. We expect, in the near future, significant advancement in our ability to understand, control, and apply these cell membrane-modified lipid-DNA conjugates. 相似文献
944.
Diabetes mellitus (DM) is the most prevalent non‐contagious disease, which has affected a large number of people all over the world. Among all treatments known to have a positive influence in the control of DM, insulin therapy is the most common and effective one. Nowadays, various methods of insulin delivery are under investigation, which are able to reach a plausible bioavailability with ignorable side effects instead of insulin injection. This article presents a comprehensive review of the insulin therapy approach with a focus on modified methods in insulin delivery strategies and current advances in engineered insulin delivery systems. 相似文献
945.
BiBi Fatemeh Mirjalili Abdolhamid Bamoniri Leila Rahmati 《Arabian Journal of Chemistry》2019,12(8):2216-2223
1-Amidoalkyl-2-naphthols were prepared via one-pot multi-component reaction of 2-naphthol, aldehydes, and amides in the presence of nano-silica supported boron trifluoride (nano-BF3·SiO2) in ethyl acetate at 80 °C. Short reaction times, high yields, scaleup and easy work-up are the advantages of this protocol. 相似文献
946.
Fatemeh Taghipour Masoud Mirzaei 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(3):231-247
The important role of pyrazine (pz) and its derivatives in fields such as biochemistry and pharmacology, as well as in the study of magnetic properties, is surveyed. Recognition of these properties without extensive investigations into their structural properties is not possible. This review summarizes interactions that exist between these organic compounds by themselves in the solid state, as well as those in coordination polymers with metal ions and in polyoxometalate‐based hybrids. Complexes based on pyrazine ligands can generate metal–organic framework (MOF) structures that bind polyoxometalates (POMs) through covalent and noncovalent interactions. Some biological and magnetic properties involving these compounds are considered and the effect of hydrogen bonding on their supramolecular architectures is highlighted. 相似文献
947.
Vahideh Mahdavi Fatemeh Ghorbani-Paji Mohammad Kazem Ramezani 《International journal of environmental analytical chemistry》2019,99(10):968-976
Currently, there is growing interest in the degradation pathways of organic contaminants such as pesticides. In the case of pesticides, the determination of metabolites in agricultural products and environment is necessary as some of them could present similar toxicity to or even higher toxicity than the parent compound. The development of analytical methodology for the identification and quantification of carbendazim fungicide and its metabolites in cucumber was studied. Cucumber (cucumis sativus) is a global food in terms of economic importance and nutritional quality. Careful optimisation of the liquid chromatography–mass spectrometry (LC-MS)/MS parameters was achieved in order to attain a fast separation with the best sensitivity. The detection was carried out on an Ion-Trap tandem mass spectrometer (MS/MS) by electrospray ionisation in positive ion mode (ESI+) with multiple reaction monitoring (MRM). 相似文献
948.
Research on Chemical Intermediates - Improvement of H-ZSM-5 catalyst to convert methanol to light olefins was studied in this research. High-silica H-ZSM-5 zeolite (Si/Al = 200)... 相似文献
949.
Research on Chemical Intermediates - Fe3O4@Cu-β-CD is a hybrid composite with high catalytic activity. Easy separation with an external magnet and recyclability are the advantages of this... 相似文献
950.
By considering the Kane-Mele-Hubbard approximation on the honeycomb lattice, we investigate the spin-spin correlation for two magnetic impurities in zigzag edge silicene-like nanoflake (ZSiLF). The dependence of the spatial behaviors of RKKY interaction on the electron-electron (e-e), intrinsic spin-orbit interactions (ISOI) and, electric field are systematically investigated. Generally, the spatial behaviors of the RKKY interaction sensitively change by changing e-e interaction and electric field strengths in the presence of ISOI. The ISOI in a ZSiLF result in long-range in-plane and Ising interactions. Moreover, e-e interaction induces non-zero Dzyaloshinsky-Moriya (DM) term and nearly distance-independent Ising interaction (similar to graphene nanoflake) in the presence of ISOI. Furthermore, with considering e-e interaction, the in-plane DM interaction increases by increasing the strengths of the electric field and ISOI. 相似文献