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991.
Nguyen Thi Dieu Thuy Guo Zhao Xiaochan Wang Emmanuel Awuah Litao Zhang 《Electroanalysis》2023,35(3):e202200194
In this study, an ion-selective electrode with a sensitive ion-to-electron transducer composed of porous laser-induced graphene (LIG) and MoS2 (LIG-MoS2/ISE) was fabricated to measure the potassium ion concentration in a greenhouse nutrient solution for soilless culture. Additionally, a more effective and low-cost method was proposed for the large-batch production and manufacture of potassium ion-selective electrodes (K+-ISEs) using the direct laser writing technique, which differs considerably from existing methods. Moreover, the sensing mechanism of the proposed LIG-MoS2/ISE for potassium ion detection was investigated. The morphology and physical properties of the LIG-MoS2/SC-K+-ISEs were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and energy-dispersive spectroscopy. Potentiometric measurements, chronopotentiometry, potentiometric water layer tests, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to evaluate the analytical performance of the newly developed K+-ISEs. A Nernstian slope of 30.1 mV/decade for the activity of potassium ions in a concentration range from 10−7 to 10−2 M was determined. The EIS and chronopotentiometry results revealed that the LIG-MoS2/SC-K+-ISE had a larger resistance and double-layer capacitance than the LIG/SC-K+-ISE. The ion-selective membrane (ISM) and solid-contact layer did not have any water film between them, according to the potentiometric water layer test. The results proved that the LIG-MoS2 nanocomposite could possibly be used as a sensitive ion-to-electron transducer to fabricate K+-ISEs. The K+-ISE fabrication method using the direct laser writing technique had a higher efficiency, enabling its broad application prospects in agriculture. 相似文献
992.
Nockemann P Thijs B Parac-Vogt TN Van Hecke K Van Meervelt L Tinant B Hartenbach I Schleid T Ngan VT Nguyen MT Binnemans K 《Inorganic chemistry》2008,47(21):9987-9999
Imidazolium, pyridinium, pyrrolidinium, piperidinium, morpholinium, and quaternary ammonium bis(trifluoromethylsulfonyl)imide salts were functionalized with a carboxyl group. These ionic liquids are useful for the selective dissolution of metal oxides and hydroxides. Although these hydrophobic ionic liquids are immiscible with water at room temperature, several of them form a single phase with water at elevated temperatures. Phase separation occurs upon cooling. This thermomorphic behavior has been investigated by (1)H NMR, and it was found that it can be attributed to the temperature-dependent hydration and hydrogen-bond formation of the ionic liquid components. The crystal structures of four ionic liquids and five metal complexes have been determined. 相似文献
993.
In the presence of indium metal, 3-iodo-2-[(trimethylsilyl)methyl]propene (1) reacts with sequentially added aldehydes to provide cis-2,6-disubstituted tetrahydropyrans in good yields. Evidence suggests that InI, formed upon aldehyde (R1CHO) allylation in aqueous media, acts as a promoter for the silyl-Prins reaction with the second equivalent of added aldehyde (R2CHO). The preparation of cyclohexenyl-fused pyrans via this one-pot, three-component coupling process is presented, as is a short formal synthesis of (+/-)-centrolobine. 相似文献
994.
Georghiou PE Dawe LN Tran HA Strübe J Neumann B Stammler HG Kuck D 《The Journal of organic chemistry》2008,73(22):9040-9047
Various tribenzotriquinacenes (TBTQs), most of which incorporate six functional groups at the periphery of their C3v-symmetrical, rigid and convex-concave molecular framework, have been studied with respect to their ability to form supramolecular complexes with the C60 and C70 fullerenes, either in the solid state or in solution. The hexabromo derivative Br6-TBTQ was cocrystallized with C60 as [Br6-TBTQ相似文献
995.
The manganese(III) complex (2) with a diamide ligand has been synthesized. This complex was found to catalyze both the epoxidation of (Z)- and (E)-stilbene with high conversion and the oxidation of benzyl alcohol to benzaldehyde. 相似文献
996.
997.
998.
Tran Duc Thiep Truong Thi An Phan Viet Cuong Nguyen The Vinh G. V. Mishinski V. I. Zhemenik 《Physics of Particles and Nuclei Letters》2016,13(4):471-479
In this work we present the isomeric ratio of fission product 135Xe in the photo-fission of actinide elements 232Th, 233U and 237Np induced by end-point bremsstrahlung energies of 13.5, 23.5 and 25.0 MeV which were determined by the method of inert gaseous flow. The data were analyzed, discussed and compared with the similar data from literature to examine the role of energy separated in fission process, excitation energy and reaction channels effects. 相似文献
999.
We use normal directions of the outcome set to develop a method of outer approximation for solving generalized convex multiobjective programming problems. We prove the convergence of the method and report some computational experiments. As an application, we obtain an algorithm to solve an associated multiplicative problem over a convex constraint set. 相似文献
1000.
In this paper, we propose a new simple explicit iterative algorithm to find a solution for variational inequalities over the set of common fixed points of an infinite family of nonexpansive mappings on real reflexive and strictly convex Banach spaces with a uniformly Gâteaux differentiable norm. Two numerical examples also are given for illustration. 相似文献