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Near-field thermophotovoltaic (NTPV) devices comprising a SiC-hBN-graphene emitter and a graphene-InSb cell with gratings are designed to enhance the performance of the NTPV systems. Fluctuational electrodynamics and rigorous coupled-wave analysis are employed to calculate radiative heat transfer fluxes. It is found that the NTPV systems with two graphene ribbons perform better due to the graphene strong coupling effects. The effects of graphene chemical potential are discussed. It is demonstrated that near-field radiative heat transfer of thermophotovoltaic devices is enhanced by the coupling of surface plasmon polaritons, surface phonon polaritons, hyperbolic phonon polaritons, and magnetic polaritons caused by the graphene strong coupling effects. Rabi splitting frequency of different polaritons is calculated to quantify the mutual interaction of graphene strong coupling effects. Finally, the effects of cell grating filling ratio are investigated. The excitation of magnetic polaritons is affected by the graphene ribbon and the cell filling ratio. This investigation provides a new explanation of the enhancement mechanism of graphene-assisted thermophotovoltaic systems and a novel approach for improving the output power of the near-field thermophotovoltaic system.

The near-field effect can be used to improve the output power of the near-field thermophotovoltaic device (NTPV). The near-field radiative heat transfer in the near-field thermophotovoltaic device can be enhanced by the excitation of hyperbolic modes and the coupling of surface plasmon polaritons. In this study, we design a two-body near-field thermophotovoltaic system based on hyperbolic metamaterial. The multilayer structure on the emitter is composed of Ga-doped ZnO (GZO) and hafnium dioxide (HfO2). The gratings are on the InAs photovoltaic cell. Fluctuational electrodynamics and rigorous coupled-wave method are employed to calculate radiative heat transfer. It is found that the NTPV system with multiple microstructures performs better than the NTPV system just with single micro-structures. This NTPV system performs better in a wider vacuum gap. The output power and efficiency are enhanced by the GZO-HfO2surface plasmon polaritons in multilayer structure. The gratings can monitor the spectral heat flux to match the cell band gap to enhance the performance of the near-field thermophotovoltaic system. This investigation provides a novel approach for improving the output power of a two-body near-field thermophotovoltaic system.

Yin (Newsletters on Stratigraphy, 2022, 55, 1–19) has suggested that there is no evidence of the Toarcian Oceanic Anoxic Event (T-OAE) in terms of organic-rich shales in the Qiangtang region, northern Tibet based on a revision data on the Jurassic ammonites from the Biluoco area. However, He used some unbelievable ammonites to determine the depositional age of the Biluoco section, and failed to constrain the age of T-OAE interval. Our data suggest that the T-OAE was extensive in the Qiangtang Basin supporting a global event. We also revised wrong information of strata in the Biluoco area in Yin (Newsletters on Stratigraphy, 2022, 55, 1–19).

Radial jet drilling (RJD) technology has been applied to enhance the recovery of difficult-to-produce reserves by multiple horizontal micro-holes. The micro-hole length drilled by high-pressure water jets is of vital importance for the oil and gas recovery effect and is usually tens of meters long for applications in maturing oil fields in China. The water jets are generated by multiple orifices nozzle generally. Many studies focused on improving the self-propelled force generated by water jets to increase the micro-hole length. However, there are few researches on improving the micro-hole extension capacity in terms of optimizing the flexible hose that acts as the drill pipe in conventional drilling technology. This paper firstly studied the relationship between the flexible hose length and the micro-hole extension limit according to the analytical model to calculate the micro-hole extension limit. Then, the method to optimize the flexible hose length and the flow rate was developed aiming to obtain maximum micro-hole extension limit. The results show that the micro-hole extension limit decreases logarithmically with the increase in the flexible hose length under the condition that the takes the maximum value. The optimization model is applied by a field case and is proved to be effective to increase the micro-hole extension limit. This study is significant to improve the micro-hole extension capacity. Moreover, it provides a reference for the design of the hydraulics and selection of flexible hose for the RJD.

Background: The sulfonyl groups are general structural moieties present in agrochemicals, pharmaceuticals, and natural products. Recently, many efforts have been focused on developing efficient procedures for preparation of organic sulfones. Materials and Methods: Water, a proton source, is considered one of the most ideal and promising solvents in organic synthesis for its easy availability, low cost, nontoxic and nonflammable characteristics. From the green and sustainable point of view, more and more reactions are designed proceeding in water. Objective: The review focuses on recent advances of sulfonylation reactions proceeding in water. Sulfonylation reactions using sodium sulfinates, sulfonyl hydrazides, sulfinic acids, and sulfonyl chlorides as sulfonating agents were introduced in detail. Results and Discussion: In this review, sulfonylation reactions proceeding in water developed in recent four yields were presented. Sulfonylation reactions using water as solvent have attracted more and more attention because water is one of the most ideal and promising solvents in organic synthesis for its facile availability, low cost, nontoxic and nonflammable properties. Conclusion: Numerous sulfonating agents such as sodium sulfinates, sulfonyl hydrazides, sulfinic acid, sulfonyl chlorides and disulfides are efficient for sulfonylation reactions which proceed in water.

The recent development about using DESs as green solvents in transition metal catalyzed organic reactions was highlighted, and Au, Metal impregnated on magnetite, Pd, Ru catalyzed organic reactions proceeded smoothly in DESs and gave corresponding products in reasonable yields. And in some cases, the catalytic systems could be recycled up to several times.

•Sr and Nd isotope analysis of Chinese standard reference materials.•First reports of Sr and Nd isotopic compositions of marine sediment standard.•GSR-1, GSR-2, GSR-3 and GBW07315 yield homogeneous Sr and Nd isotope results.

The recent development in transition metal catalyzed cross coupling of nitroarenes was highlighted. And nitroarenes were efficient electrophilic coupling partners for constructing C–O, C–S, CC and C–N bonds.

We demonstrate a general approach to splicing microfibers via polymer nanowires. Chloroform dissolved polystyrene nanowires are used to splice silica, tellurite glass, and semiconductor microfibers or nanowires, with splicing loss down to 0.51 dB. Using spliced microfiber structures, we also demonstrate microfiber ring resonators and Mach–Zehnder interferometers with high robustness. The splicing technique demonstrated here promises high potentials for robust optical integration of microfibers or nanowires for functional circuits or devices.