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51.
Novel polyimides obtained from a new aromatic diamine (BAPO) containing pyridine and 1,3,4‐oxadiazole moieties for removal of Co(II) and Ni(II) ions 下载免费PDF全文
Novel, thermally stable polyimides (PIs) containing a 1,3,4‐oxadiazole and pyridine moieties based on a new aromatic diamine 2,5‐bis‐(aminopyridine‐2‐yl)‐1,3,4‐oxadiazole, BAPO, were synthesized. The prepared polymers were soluble in dimethysulfoxide (DMSO) and concentrated sulfuric acid at room temperature as well as in polar and aprotic solvents, such as, N‐methylpyrrolidone (NMP) and N,N‐dimethylacetamide (DMAc) at elevated temperature. Thermal behaviors of the PIs were studied by thermogravimetric analysis/dynamic thermal analysis (TGA‐DTA) and differential scanning calorimetry (DSC). The inherent viscosities of the PI solutions were in the range of 0.38–0.61 dl/g (in DMSO with a concentration of 0.125 g/dl at 25 ± 0.5°C). The removal of Co(II) and Ni(II) ions from aqueous solutions was performed using polymer 6, which was obtained from BAPO and 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA). The maximum adsorption capacity was observed for Co(II) ion at pH = 7.0 (110.4 mg g?1, 1.87 mmol g?1). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
52.
Revealing the Preferred Interlayer Orientations and Stackings of Two‐Dimensional Bilayer Gallium Selenide Crystals 下载免费PDF全文
Dr. Xufan Li Dr. Leonardo Basile Dr. Mina Yoon Dr. Cheng Ma Dr. Alexander A. Puretzky Dr. Jaekwang Lee Dr. Juan C. Idrobo Dr. Miaofang Chi Dr. Christopher M. Rouleau Dr. David B. Geohegan Dr. Kai Xiao 《Angewandte Chemie (International ed. in English)》2015,54(9):2712-2717
Characterizing and controlling the interlayer orientations and stacking orders of two‐dimensional (2D) bilayer crystals and van der Waals (vdW) heterostructures is crucial to optimize their electrical and optoelectronic properties. The four polymorphs of layered gallium selenide (GaSe) crystals that result from different layer stackings provide an ideal platform to study the stacking configurations in 2D bilayer crystals. Through a controllable vapor‐phase deposition method, bilayer GaSe crystals were selectively grown and their two preferred 0° or 60° interlayer rotations were investigated. The commensurate stacking configurations (AA′ and AB stacking) in as‐grown bilayer GaSe crystals are clearly observed at the atomic scale, and the Ga‐terminated edge structure was identified using scanning transmission electron microscopy. Theoretical analysis reveals that the energies of the interlayer coupling are responsible for the preferred orientations among the bilayer GaSe crystals. 相似文献
53.
54.
Zahra Najafi Mohammad Mahdavi Maliheh Safavi Mina Saeedi Heshmatollah Alinezhad Mahboobeh Pordeli Sussan Kabudanian Ardestani Abbas Shafiee Alireza Foroumadi Tahmineh Akbarzadeh 《Journal of heterocyclic chemistry》2015,52(6):1743-1747
New derivatives of triazole‐isoxazole were synthesized through a four‐step reaction starting from various ethyl 4‐aryl‐2,4‐dioxobutanoate derivatives. Finally, all compounds were examined by MTT assays for cytotoxic activity in two human breast cancer cell lines (MCF‐7 and T‐47D). 相似文献
55.
Novel 1,2,3,4‐Tetrahydroquinazolinones via Reaction of 2‐Amino‐N‐substituted Benzamides and Dimethyl Acetylenedicarboxylate 下载免费PDF全文
Semiramis Nahavandian Sadegh Allameh Mina Saeedi Shirin Ansari Mohammad Mahdavi Alireza Foroumadi Abbas Shafiee 《Helvetica chimica acta》2015,98(7):1028-1033
Reaction of 2‐amino‐N‐substituted benzamides and dimethyl acetylenedicarboxylate (DMAD) in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in H2O at room temperature led to the formation of novel 1,2,3,4‐tetrahydroquinazolinones. 相似文献
56.
Chemical looping combustion (CLC) is a novel method of carbon capture and sequestration. It facilitates CO2 capture by lower energy penalties compared with other methods in this category. The major challenges encountered in CLC are oxygen carrier, reactor and fuel-type selection. A proper combination of these factors is required for an efficient CLC. There have been several studies with regard to oxygen carriers applicable to these processes: novel oxygen carriers, single perovskites and potential oxygen carriers, double perovskites, have been investigated for their oxygen capture and release properties in a number of studies. Different kinds of reactors have also been proposed for use in CLC processes. This paper presents information on the materials capable of oxygen storage and release and the different kinds of reactors investigated for CLC in different studies. It has been shown that, although there are several oxygen carriers and reactors with the desired function and efficiency for CLC, there remains the need for further improvement and optimisation in both areas. © 2014 Institute of Chemistry, Slovak Academy of Sciences 相似文献
57.
Molecular dynamics simulations and umbrella sampling have been used to investigate the sliding of distamycin anticancer drug along the DNA minor groove. The potential energy surface calculated for the sliding of drug shows three minima. The global minimum corresponds to the binding of drug to the AT-rich region, which is the origin of sequence selectivity of distamycin. This selectivity originates from both structural factors and energy contributions. The analysis of energy contributions of binding was performed by the MM–PBSA method. The analysis of hydrogen bonds and van der Waals, electrostatic, and solvation interactions show that structural or steric factors are more important in the selectivity of distamycin than energetic factors. The results of this study can be applied in the design of new derivatives of distamycin anticancer drug with improved properties. 相似文献
58.
A novel synthesis of thioxo-quinazolino[3,4-a]quinazolinone framework was developed through a four-step reaction starting from isatoic anhydride. The resulting 2-aminobenzamides from the reaction of isatoic anhydride and different amines underwent coupling–cyclization reaction with 2-nitrobenzaldehydes, reduction of nitro group, and then cyclization reaction with carbon disulfide (CS2). All steps were carried out under easy and user-friendly conditions in a short time without using expensive catalysts or reagents.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
59.
Soghra Farzipour Mina Saeedi Mohammad Mahdavi Hossein Yavari Mohammadreza Mirzahekmati Nasser Ghaemi 《合成通讯》2014,44(4):481-487
Clean and easy preparation of quinazolin-4(3H)-one derivatives using 2-aminobenzamides and Vilsmeier reagent is described. 2-Aminobenzamides were converted into the corresponding quinazolinones under mild and efficient conditions, in good yields without undesirable by-products.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
60.
Paradise CL Sarkar PR Razzak M De Brabander JK 《Organic & biomolecular chemistry》2011,9(11):4017-4020
Amino acid-derived propargylic amides are cyclised in a one-pot, Au(III)-catalysed operation to yield 5-bromomethyl oxazoles. These compounds are further elaborated to bis-heterocycles, dipeptide mimics and more. 相似文献