RESUMO
The detection of nitro compounds and removal of organic dyes remain urgent issues because they are poisonous to humans. Taking advantage of metal-organic framework (MOF) materials, we demonstrate herein an indium-organic framework (InOF) exhibiting sensitive fluorescence sensing of nitro compounds, prominent dye capture, and excellent photodegradation of dyes. By using 4,4',4â³-s-triazine-1,3,5-triyltri-p-aminobenzoate (TATAB), an amino-functionalized BTB-like linker, the 3D SNNU-110 structure ({[In3OCl(H2O)2(TATAB)2]}n) is formed. SNNU-110 shows a 3,6-connected 3,6T22 topology with TATAB and [In3O(CO2)6] tricapped trigonal-prismatic clusters as 3- and 6-connected nodes. Thanks to the fluorescence properties and amine recognition sites of TATAB, SNNU-110 exhibits excellent performance of fluorescence quenching for six electron-deficient nitroaromatics. The intercrossing 1D channels in SNNU-110 formed from the a- and b-axis directions with dimensions of about 18 Å × 11 Å can capture diverse cationic, anionic, or neutral dyes effectively. What is more, the existence of an inorganic [In3O] cluster enable SNNU-110 to be a good photocatalyst. Upon irradiation with a 300 W xenon lamp, SNNU-110 shows outstanding photocatalytic activity toward rhodamine B (RhB) and methylene blue (MB), and there was almost no degradation. The catalytic activity can retain about 94.6% (RhB) and 93.1% (MB), respectively. Overall, SNNU-110 fully demonstrates the power of multicomponent MOFs, which provide a feasible route for the design of functional materials toward to pollutant identification and removal applications.
RESUMO
The water-soluble polypyridine copper complex [Cu(F3TPA)(ClO4)2] [1; F3TPA=tris(2-fluoro-6-pyridylmethyl)amine] catalyzes water oxidation in a pH 8.5 borate buffer at a relatively low overpotential of 610 mV. Assisted by photosensitizer and an electron acceptor, 1 also exhibits activity as a homogeneous catalyst for photo-induced O2 evolution with a maximum turnover frequency (TOF) of (1.58 ± 0.03) × 10(-1) s(-1) and a maximum turnover number (TON) of 11.61 ± 0.23. In comparison, the reference [Cu(TPA)(ClO4)2] [TPA=tris(2-pyridylmethyl)amine] displayed almost no activity under either set of conditions, implying the crucial role of the ligand in determining the behavior of the catalyst. Experimental evidence indicate the molecular catalytic nature of 1, leading to a potentially practical strategy to apply the copper complex in a photoelectrochemical device for water oxidation.
RESUMO
A novel, hydrophilic and recyclable methoxypolyethylene glycol (PEG)-modulated s-triazine-based multifunctional Schiff base/N,P-ligand L9 was prepared and used in Pd-catalyzed Heck-type carbonylative coupling reactions, affording diverse chalcone derivatives and 1,4-dicarbonyl esters in good yields.
RESUMO
Organic solid fluorophores with a tunable emission color have been widely applied in multiple areas. However, rational design and efficient crafting of these fluorophores from a simple core skeleton is still a formidable challenge because of the undesirable concentration quenching emission effect. Herein, we present the development of two series of organic solid fluorophores based on a backbone of p-bis(2,2-dicyanovinyl)benzene. Notably, the introduction of either non-aromatic or aromatic substituents provides fluorophores with a tunable emission color. Moreover, the fluorophores with aromatic substituents exhibit additional unique optical phenomena, such as aggregation-induced emission, polymorphism-dependent emission, and reversible mechanochromic luminescence.
RESUMO
Nationwide surveys of food and nutrient intake in China have revealed geographical variation between urban and rural areas. This study developed a semi-quantitative food frequency questionnaire (SQFFQ) for cancer risk assessment suitable for both urban and rural populations by conducting a survey of food intake in Chongqing, China. We recruited 100 urban and 104 rural healthy residents aged from 35 to 55 years in Chongqing, and collected dietary data with 3-day weighed records to assist in the development of the SQFFQ. The intake of 35 nutrients was calculated according to Standard Food Composition Tables for China and Japan. For each nutrient estimated by percentage contribution analysis (CA) and multiple regression analysis (MRA), foods with up to a 90% contribution or a 0.90 cumulative R(2) were selected as items for SQFFQs. The food items of the combined SQFFQ were selected from all items listed in either urban or rural SQFFQs. Mean intake of energy, protein and carbohydrate did not differ between the urban and rural residents. The latter consumed more fat than their urban counterparts. We selected 119 food items for the combined SQFFQ, comprising 22 specific items for the urban SQFFQ, 6 for the rural, and 78 common and 13 additional items. The combined SQFFQ covered 33 nutrients with up to a 90% contribution in each area. We were able to develop a data-based SQFFQ that can estimate nutrient intake of both urban and rural populations, with suitable coverage rates. Further reliability and reproducibility tests are now needed to assess its applicability.