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Comprehensive Summary: We report herein an unprecedented N‐heterocyclic carbene‐catalyzed formal [3 + 3] annulation of ynals with N‐Ts indolin‐3‐ones under the oxidation condition affording the functionalized pyrano[3,2‐b]indol‐2‐ones. The alkynyl acylazoliums via the combination of a carbene with ynals in the presence of oxidate proved to be the important intermediates for the success of this transformation. This method features a broad substrate scope and mild conditions, including axially chiral skeletons with suitable substitutions. [ABSTRACT FROM AUTHOR]

In this paper, a new type of structured electron beam is introduced, which is the electron Airy tornado wave (eATW) with the characteristics of abrupt auto‐focusing and rotation property in free space. It is also found that the eATWs propagate periodically in a magnetic field, and their patterns of intensity distributions show the time‐like axial symmetry about a half‐period point in a period of time. Furthermore, the influence of the magnetic field's magnitude and direction on eATWs with different parameters has also been discussed. [ABSTRACT FROM AUTHOR]

This paper analytically and numerically proposes the propagation dynamics of the symmetric Pearcey Gaussian vortex beam (SPGVB) in the uniformly moving parabolic potential. The optical vortex located in the initial plane produces a vortex channel in the presence of the uniformly moving parabolic potential, called the vortex trajectory. The vortex trajectory can be manipulated dynamically by configuring different combinations of the parameters, and the optical intensity and the focal position can also be affected. Moreover, the spatial dynamic vortex trajectory is derived analytically, and the 2D on‐axis and off‐axis vortex scenarios are also presented. Our work expands the methods of the vortex trajectory manipulation and may broaden more practical potential applications in the particle manipulation. [ABSTRACT FROM AUTHOR]

A new sorbent S-benzyldithiocarbazate (SBDTC) modified activated carbon (AC-SBDTC) was prepared and studied for preconcentration for trace mercury(II) prior to inductively coupled plasma atom emission spectrometry (ICP-AES). The experimental conditions were optimised with respect to different experimental parameters using both batch and column procedures in detail. The optimum pH value for the separation of Hg(II) on the new sorbent was 3, while the adsorption equilibrium was achieved in less than 5 min. Complete elution of the adsorbed metal ions from the sorbent surface was carried out using 5 mL of 0.25 mol L-1 of HCl and 2% CS(NH2)2. Common coexisting ions did not interfere with the determination. The maximum static adsorption capacity of the sorbent under optimum conditions was found to be 0.55 mmol g-1. The detection limit of the present method was found to be 0.09 ng mL-1, and the relative standard deviation (RSD) was lower than 2.0%. The procedure was validated by analysing the certified reference river sediment material (GBW 08301, China), the results obtained were in good agreement with standard values. This sorbent was successfully employed in the separation and preconcentration of trace Hg(II) from the natural water samples yielding 80-fold concentration factor. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: We report herein an unprecedented N‐heterocyclic carbene‐catalyzed formal [3 + 3] annulation of ynals with N‐Ts indolin‐3‐ones under the oxidation condition affording the functionalized pyrano[3,2‐b]indol‐2‐ones. The alkynyl acylazoliums via the combination of a carbene with ynals in the presence of oxidate proved to be the important intermediates for the success of this transformation. This method features a broad substrate scope and mild conditions, including axially chiral skeletons with suitable substitutions. [ABSTRACT FROM AUTHOR]

Abstract: A procedure for separation and preconcentration trace amount of Cu(II), Fe(III) and Pb(II) by 2-((2-aminoethylamino)methyl)phenol-functionalized activated carbon (AC-AMP) packed column has been proposed. Under the optimized conditions (pH 4, flow rate 2.0mLmin−1), Cu(II), Fe(III) and Pb(II) were retained on the column, then quantitatively eluted by 2mL 1molL−1 nitric acid solution and determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). The tolerance limits of electrolytes were very high. The adsorption capacity of AC-AMP was found to be 12.1, 67.1, and 16.2mgg−1 for Cu(II), Fe(III), and Pb(II), respectively. According to the definition of International Union of Pure and Applied Chemistry, the detection limits (3σ) of this method for Cu(II), Fe(III) and Pb(II) were 0.27, 0.41 and 0.16μgL−1, respectively. The relative standard deviation under optimum conditions is less than 3.0% (n =11). The proposed method has been validated by analyzing a certified reference material and successfully applied to the preconcentration and determination of Cu(II), Fe(III), and Pb(II) in actual samples with satisfactory results. [Copyright &y& Elsevier]

In this Letter, we introduce a new, to the best of our knowledge, class of accelerating surface plasmonic wave: the Olver plasmon. Our research reveals that such a surface wave propagates along self-bending trajectories at the silver-air interface with various orders, among which Airy plasmon is regarded as the zeroth-order one. We demonstrate a plasmonic autofocusing hot-spot by the interference of Olver plasmons and the focusing properties can be controlled. Also, a scheme for the generation of this new surface plasmon is proposed with the verification of finite difference time-domain numerical simulations.

The Talbot-like effect of symmetric Pearcey beams (SPBs) is presented numerically and experimentally in the free space. Owing to the Talbot-like effect, the SPBs have the property of periodic, multiple autofocusing and self-healing. Meanwhile, the focusing positions and focusing times of SPBs are controlled by the beam shift factor and the distribution factors. Furthermore, the beam shift factor can also affect the Talbot-like effect and the Talbot period. It is believed that the results can diversify the application of the Talbot effect.

In this Letter, a new class of an accelerating self-imaging surface plasmonic wave, the Airy-Talbot plasmon, is introduced for the first time, to the best of our knowledge. Our research shows that such a surface wave propagates at the interface between metal (silver) and a dielectric material (air) and causes a strong interference along curved trajectories, which generates the Talbot effect in the surface. The propagation properties have potential value in nanoscale plasmonic devices. A scheme for generating this novel plasmon theoretically is proposed, and we prove it by finite difference time-domain numerical simulations.

A one-pot synthesis of azaheterocyclo[1,2,3-lm]-fused benzo[c]carbazoles (2 and 3) has been developed by photocyclization of 3-acyl-2-halo-1-[(ω-phenylethynyl)alkyl] indoles (1) in good to excellent yields. All products are formed from 1 via two sequential photocyclization reactions. Two products, 9-chloro-7,8-dihydro-6H-benzo[c]pyrido[1,2,3-lm]carbazole (2a-h) and 7,8-dihydro-6H-benzo[c]pyrido[1,2,3-lm]carbazole (3a-h), are produced in the photocyclization of 2-halo-1-[(ω-phenylethynyl)alkyl]indole-3-carbaldehydes (1a-h). In contrast, only products 2a-h are produced in the photocyclization of 3-acetyl-2-chloro-1-[(ω-phenylethynyl)alkyl]indole-3-carbaldehydes (1o-t). The 9-H in 3a-h (n = 2) does originate from the formyl group in 1a-h via 1,5-hydrogen shift. The structures of three new products, 9-bromo-7,8-dihydro-6H-benzo[c]pyrido[1,2,3-lm]carbazole (2b), 9-chloro-10-methyl-7,8-dihydro-6H-benzo[c]pyrido[1,2,3-lm]carbazole (3h) and 12-chloro-7,8-dihydro-6H-benzo[c]pyrido[1,2,3-lm]carbazole (2w), have been corroborated by single-crystal X-ray structural analyses.