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991.
This review supplied direct insight of host-guest molecule system by using COR as the guest molecule.  相似文献   
992.
Wang  Lijuan  Li  Xiaoyan  Zeng  Yanli  Meng  Lingpeng  Zhang  Xueying 《Structural chemistry》2019,30(4):1301-1313
Structural Chemistry - The bimolecular and termolecular complexes involving F2TO (T = Si, Ge, Sn) and XCN/BrY (X = H, Br, CH3, and PH2; Y = F, CN, OH, and H)...  相似文献   
993.
In this study, a novel dopamine modified graphene‐based photocatalytic membrane with Bi12O17Cl2 inserted was fabricated to modify the commercial cellulose acetate membrane via vacuum filtration method. Results showed the reduced graphene oxide (RGO)/poly(dopamine) (PDA)/Bi12O17Cl2‐CA photocatalytic composite membrane exhibited 98% removal efficiency for methylene blue (MB) within 100 minutes and 96% removal efficiency for 4‐CP within 160 minutes. Importantly, the photocatalytic composite membrane can simultaneously achieve dye degradation and oil‐water separation in only one device within a short time. And the as‐prepared membrane displayed great antifouling performance and recyclability after 10 cycles. Meanwhile, the membrane showed excellent stability in the agitated water bath or different pH conditions. In summary, the photocatalytic membrane investigated in this study opens new avenue for treatment of wastewater.  相似文献   
994.
While conventional approaches have been studied for removal of ruthenium(III) ions (Ru(III)), this work focuses on the applicability of ion‐imprinted poly(methyl methacrylate‐vinyl pyrrolidone)/poly(vinylidene fluoride) blending membranes (Ru(III)–ion‐imprinted membrane[IIM]) for selective removal of Ru(III) from acidic water solutions. In order to measure the effectiveness of these imprinted membranes, after fabrication, binding experiments were done with aqueous Ru(III) solutions. The results showed that Ru(III)‐IIMs were fabricated successfully at various blending ratios, and their chemical components, microstructures, hydrophilicity, and water fluxes were measured. In pH range 0.5 to 5.0, binding capacity (Qe) of Ru(III) onto Ru(III)‐IIM increases remarkably with pH and then reaches to a maximum value (53.52 mg/g) at pH 1.5. After that, Qe gradually decreases. Compared with a nonimprinted membrane, Ru(III)‐IIM demonstrates higher selectivity for Ru(III) at pH 1.5 in the presence of Ni(II) and Cu(II) ions, and its selectivity coefficients for Ru(III)/Ni(II) and Ru(III)/Cu(II) are 3.70 and 3.32, respectively. Also, Ru(III)‐IIM shows a good chemical stability and reusability. C─N and C═O bonds within poly(vinyl pyrrolidone) segments of poly(methyl methacrylate‐vinyl pyrrolidone) (P(MMA‐VP)) participate the uptake of Ru(III). Ru(III)‐IIM exhibited excellent hydrophilicity and Ru(III) selective adsorption ability and reusability and has potential to be used for Ru(III) removal from acidic water solutions.  相似文献   
995.
An Fe(OTf)3-catalyzed intramolecular hydroarylation of arene-alkynes with high functional group tolerance has been reported, affording a series of phenanthrene derivatives efficiently. A low catalytic amount of Fe(OTf)3 is applied in this reaction. This transformation provides a convenient and practical method for the preparation of phenanthrenes.  相似文献   
996.
Hybrid organic–inorganic materials have been considered as a new candidate in the field of thermoelectric materials since the last decade owing to their great potential to enhance the thermoelectric performance by utilizing the low thermal conductivity of organic materials and the high Seebeck coefficient, and high electrical conductivity of inorganic materials. Herein, we provide an overview of interfacial engineering in the synthesis of various organic–inorganic thermoelectric hybrid materials, along with the dimensional design for tuning their thermoelectric properties. Interfacial effects are examined in terms of nanostructures, physical properties, and chemical doping between the inorganic and organic components. Several key factors which dictate the thermoelectric efficiency and performance of various electronic devices are also discussed, such as the thermal conductivity, electric transportation, electronic band structures, and band convergence of the hybrid materials.  相似文献   
997.
998.
One new indole-type alkaloid, α-L-rhamnopyranosyl-(1→6)-β-D- glucopyranosyl 6-methoxy-3-indolecarbonate (1), together with three known alkaloids (24), one aromatic acid (5) and five known saponins (610), was isolated from the roots of Clematis florida var. plena. Their structures were established by NMR spectroscopic analysis and acid hydrolysis. In in vivo anti-inflammatory activity, n-butanol extract was found to be potent against ear edema in mice, with inhibition rate of 48.7% at a dose of 800?mg/kg. Furthermore, compounds 8 and 9 obtained from the n-butanol extract exhibited significant anti-inflammatory activities with inhibition rates of 50.9% and 54.7% at a dose of 200?mg/kg.  相似文献   
999.
Based on the anomaly cancellation method, initiated by Robinson and Wilczek, we investigate Hawking radiation from the event horizon and cosmological horizon of the higher dimensional Reissner–Nordström–de Sitter black hole via covariant gauge and gravitational anomalies. Unlike in black hole space-time, to describe the observable physics, the effective field theory here is constructed between the event horizon and cosmological horizon. Our result shows that to restore the underlying gauge covariance and diffeomorphism covariance at the quantum level, the covariant compensating fluxes of gauge and energy–momentum tensor, which are shown to equal to those of Hawking radiation, should be radiated from the event horizon and absorbed from the cosmological horizon, respectively.  相似文献   
1000.
The recent work of Robinson and Wilczek that Hawking radiation can be determined by the compensating fluxes is extended to the charged and magnetized Reissner-Nordström de Sitter black hole. We reconstruct the electromagnetic field tensor and the Lagrangian of the field corresponding to the source with electric and magnetic charges to redefine an equivalent charge and gauge potential. We construct the effect field theory between the event horizon and cosmological horizon to respectively determine the compensating fluxes from them, which are shown to exactly equal to those of Hawking radiation, by the covariant anomaly cancellation conditions.  相似文献   
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