查看更多>>摘要：Considering the phosphorus pollution in the water and the shortage of phosphate rock resources, the TiO2*/Fe3O4 composite is prepared by sol-gel method to adsorb and recover phosphate from wastewater. The physiochemical properties combined with adsorption experiment results show that the phosphate adsorption of TiO2*/Fe(3)O(4 )is mono-layer chemical adsorption with electrostatic attraction and ligand exchange. The adsorption capacity reaches 64.6 mg/g at 25 degrees C in pH 6 and the phosphate recovery rate is over 85% after 5 recycling times. The TiO2*/Fe3O4, which is easily separated magnetically from water with excellent phosphate removal performance of municipal sewage, is a promising specific phosphate adsorbent.
查看更多>>摘要：Density functional theory calculations are used to explore the Li storage capacity of Ng(m) endohedral C-60 fullerenes (Ng = He, Ne, Ar, Kr, Xe; m = 1, 2). Formation energies of Ng endohedral fullerenes are negative, ranging from -2.65 to -13.11 kcal/mol (at the PBE/DNP level). The incorporation of Ng and Ng(2) moieties into C-60 enhances the adsorption energy of Li. The maximum adsorption energy of the Li atom on Xe-2 encapsulated C-60 is about -45 kcal/mol, which is 7% larger than that of on pure C-60. The presence of Ng atoms lowers the energy barrier for Li migration to neighboring pentagon or hexagon rings.
查看更多>>摘要：New emitters with deeply red emission and slow efficiency roll-off in non-doped organic light-emitting diodes (OLEDs) are highly expected. In this work, we used our recently developed 2-phenylbenzo[g]furo[2,3-b]-quinoxaline as the acceptor (A) and triphenylamine (TPA) as the donor (D), synthesized a D-A type red emitter, TPA-PFQ. The TPA-PFQ presented a high quantum yields of 88.03% in toluene solution. Using it as emitter, the non-doped OLEDs showed a saturated red emission with a peak of 620 nm and a maximum luminance of 11190 cd m(-2). Moreover, the non-doped OLEDs presented a maximum EQE of 2.09% (2.47 cd A(-1)) at 100 cd m(-2), and remained 2.0% (2.40 cd A(-1)) at 1000 cd m(-2), 2.03% (2.49 cd A(-1)) at 5000 cd m(-2), only 2.9% efficiency roll-off with the luminance changed from 100 cd m(-2) to 5000 cd m(-2). Our experiments demonstrated benzo[g]furo[2,3-b]quinoxaline skeleton could serve as a promising acceptor unit for constructing deep red emitters.
Prasad, M. B. SaiGhosh, A.Dwivedi, T.Chakraborty, G....
4页
查看更多>>摘要：The importance of Mo-98/100 in producing Tc-99m, a radio tracer that is in ever increasing demand, is very well-known. We present here our results of experiments carried out to enrich Mo-98/100 by the process of multi-photon dissociation of MoF6 under cooled conditions (58 degrees C). Selective excitation of the combination mode (v(3) + v(5)) lying in the 1050 cm(-1) region was possible by the 9 mu m band emission lines of a CO2 laser. A maximum enrichment factor of similar to 1.12 for the case of Mo-100 was achieved upon irradiation with the 9P(10) line that is near-resonant to (MoF6)-Mo-92.
查看更多>>摘要：The light harvesting and separation of charge carriers are two decisive factors in the photocatalytic process. In order to reveal the synergic effects of light absorption and separation of charge carriers, and put forward the optimal band gaps of specific photocatalytic systems, Bi8V2O17, Bi4V2O11, BiVO4 and Bi4V6O21 series samples with the V/Bi = 0.25, 0.5, 1 and 1.5 were successfully designed and synthesized. UV-Vis diffuse reflectance spectra (DRS) indicated that the visible light harvesting was tremendously enhanced with the increase of V/Bi ratio. Due to the narrow down of band gaps, photoluminescence (PL) illustrated that the separation of electron-hole pairs was gradually restrained. Although Bi(8)V(2)O(17 )showed the best separation of electron-hole pairs, and Bi4V6O21 had the best light harvesting range, but the photocatalytic experiments showed that the optimal sample is Bismuth vanadate (BiVO4). Density functional theory (DFT) calculation has been utilized to explain the above inconsistency, and a promising formula has been put forward to calculate the regularity of light harvesting and separation of electron-hole pairs in the photocatalytic systems. This work constructed the relation between light absorption and separation of electron-hole pairs, and creatively proposed a reliable band gap calculation method to forecast and design of efficient photocatalysts.
查看更多>>摘要：In this work, ZnB2O4:Mn2+ with a centrosymmetric structure was synthesized, which was further composited into the polydimethylsiloxane elastomer. The results suggest that the ZnB2O4:Mn2+/polydimethylsiloxane elastomer exhibits intense green mechanoluminescence, which is trap-independent and self-recoverable. The repeatable stretching tests along the horizontal and vertical directions further suggest that the interfacial rubbing should be crucial to the mechanoluminescence, and therefore the underlying mechanisms are proposed. This work not only reports a mechanoluminescent material with the centrosymmetric structure, but also reveals the underlying mechanisms from the viewpoint of interfacial interactions, which should be valuable for the future development of various mechanoluminescent materials.
Maia da Costa, M. E. H.Barrozo, P.Silva Jr, R. S.Ferreira, N. S....
7页
查看更多>>摘要：We investigate the Sr2+-doping influence on the structural, chemical, and magnetic properties of LaCrO3 prepared by a modified combustion method. X-ray diffraction (XRD) results indicate that samples crystallized in an orthorhombic structure, which were stable in heat treatments lower 1073 K. X-ray photoelectron spectroscopy (XPS) results showed a tendency to favor the oxidize of Cr3+ forming more Cr4+ and Cr6+ ions for the La0.9Sr0.1CrO3. The magnetic measurements reveal that the Sr2+-doping does not change the antiferromagnetic order of LaCrO3 but induces a slight decrease in the magnetic transition temperature, multiple magnetic transitions, and an increase in the hysteresis opening, which are associated with a decrease of the spin canted that favors the Cr3+-O-Cr4+ double exchange interactions.
Santos-Jr, Carlos V.Kraka, ElfiMoura Jr, Renaldo T.de Souza, MigueL A. F....
7页
查看更多>>摘要：In this work, Cl- +AR(3)Cl reactions (with A = C and Si, and R = H, Me, Et, Cl, and F) were investigated to evaluate the A-R spectator bond properties at the omega-B97X-D/SPK-TZP level of theory, applying the Quantum Theory of Atoms in Molecules, the Overlap Model, and Local Vibrational Mode theory. The different chemical bond ana -lyses converge to the conclusion (in line with current literature) that the steric hindrance experienced by Cl- in SN2@C reactions can be viewed as a consequence of the greater covalent nature of C-R bonds that concentrate density in bond region more efficiently than Si-R.
查看更多>>摘要：Herein, we presented the preparation of N-doped porous carbon from lab used filter paper. Filter paper was first carbonized at 500 degrees C. The obtained carbon was then pyrolyzed with KHCO3 and urea. Effects of KHCO3 activation on the carbons' physicochemical properties were thoroughly investigated. The derived carbon materials were also tested for CO2 adsorption with pressure up to 20 bar. The carbons exhibited very high CO2 uptake of 19.65 mmol/g at 0 degrees C and 20 bar. The correlations between adsorption performances and the carbons' physicochemical properties at 1/20 bar were analyzed and discussed.
NSTL
Elsevier