Hole blocking layer with pinhole-free and excellent electron conductivity is critical in high-efficient perovskite solar cells. In this paper, we investigated thoroughly the effect of tantalum (Ta) ...or niobium (Nb) dopant in TiO2 compact layer. Both Ta and Nb dopants could enhance the electron conductivity of TiO2 compact film without declining their light transmittance property. The PSCs assembled with Ta or Nb-doped TiO2 blocking layer exhibited an evident promotion in short-circuit current density, and the best-performing PSCs had conversion efficiency enhancement from 13.66% (pure TiO2) to 14.41% (Ta-doped TiO2) and 14.29% (Nb-doped TiO2). Moreover, the reproducibility of PSCs was preferable with 3% Ta and 3% Nb-doped TiO2 blocking layer. Besides, the increased conductivity of doped TiO2 compact layer efficiently suppressed the J-V hysteresis of PSCs under different scan directions. PL and EIS results further revealed that the doped-TiO2 compact layer could accelerate electron transfer rate and decrease the recombination probability at TiO2/perovskite interface.
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•TiO2 dense layer was doped with tantalum or niobium in perovskite solar cells.•Ta or Nb-doped TiO2 blocking layer could effectively promote PSCs performance.•The doping strategy could enhance charge transfer at TiO2/perovskite interface.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Diesel engine combustion becomes very rough or even detonation under high altitude conditions, which is harmful to components durability. In this study, combustion characteristics were experimentally ...investigated on a V6 heavy-duty diesel engine using by a plateau simulation test bench to simulate altitude conditions of 1000 m, 3000 m and 4500 m. Results show that extremely high peak pressure rise rates of above 50bar/°CA exist at low speeds under the altitude of 4500 m. This indicates that not only does knocking combustion exist in spark-ignition (SI) engines, but also can be found in compression-ignition (CI) engines. Knock intensity (KI) is calculated by the pressure oscillation with high-pass filtering (HPF). Approach of cycle to cycle variation was adopted to study combustion characteristics on the comparisons of knock and non-knock states. Also, the correlation between KI and peak pressure rise rate was revealed through the linear regression method.
Organic dyes and molecular catalysts co-adsorbed on a metal oxide substrate are widely employed for water-splitting photoelectrodes. In this manuscript, we employ first-principles calculations to ...investigate interactions between a coumarin dye and a molecular catalyst on the nickel oxide substrate in an experimentally verified water-splitting photocathode. The nanoscopic interfacial structures and interfacial charge transfer properties of dye/catalyst/metal oxide hybrid systems in the water-splitting photocathode are elucidated. In particular, the intermolecular hydrogen bond and the substrate-to-catalyst electron transfer stabilize the interfacial structure. The present study helps the fundamental understanding of water-splitting photoelectrodes co-adsorbed with organic dyes and molecular catalysts.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract Over the course of his career, Fuqing Zhang drew vital new insights into the dynamics of meteorologically significant mesoscale gravity waves (MGWs), including their generation by unbalanced ...jet streaks, their interaction with fronts and organized precipitation, and their importance in midlatitude weather and predictability. Zhang was the first to deeply examine “spontaneous balance adjustment”—the process by which MGWs are continuously emitted as baroclinic growth drives the upper-level flow out of balance. Through his pioneering numerical model investigation of the large-amplitude MGW event of 4 January 1994, he additionally demonstrated the critical role of MGW–moist convection interaction in wave amplification. Zhang’s curiosity-turned-passion in atmospheric science covered a vast range of topics and led to the birth of new branches of research in mesoscale meteorology and numerical weather prediction. Yet, it was his earliest studies into midlatitude MGWs and their significant impacts on hazardous weather that first inspired him. Such MGWs serve as the focus of this review, wherein we seek to pay tribute to his groundbreaking contributions, review our current understanding, and highlight critical open science issues. Chief among such issues is the nature of MGW amplification through feedback with moist convection, which continues to elude a complete understanding. The pressing nature of this subject is underscored by the continued failure of operational numerical forecast models to adequately predict most large-amplitude MGW events. Further research into such issues therefore presents a valuable opportunity to improve the understanding and forecasting of this high-impact weather phenomenon, and in turn, to preserve the spirit of Zhang’s dedication to this subject.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Since the doubly clamped beam-type N/MEMS subjected to the van der Waals attraction is transformed into a mathematical model through Galerkin method, which is a nonlinear differential equation, the ...spreading residue harmonic balance method is introduced to solve the approximate solution of the nonlinear problem in this paper. The spreading residue harmonic balance method is developed on the basis of the residue harmonic balance method. The disadvantage of the approach is small parameter assumption is needed. In order to improve the accuracy of the approximate solution, the residual of the former order harmonic approximation is introduced. Besides, we compare the second-order spreading residue harmonic balance method solution with the numerical one by the Runge–Kutta method. This proves the availability and validity of spreading residue harmonic balance method.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
A two-degree-of-freedom coupled Duffing system with time delay is studied by a modified homotopy analysis method. First, a detailed calculation is given for the system. Second, single periodic and ...period-doubling solutions are obtained by solving the constructed nonlinear algebraic equation. Third, upon comparison of the periodic solution obtained by the multi-frequency homotopy analysis method with the numerical solutions obtained by the numerical method, it is found that the approximate solution agrees well with the numerical solution for the system. Finally, we discuss the convergence control parameters and convergence control function.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Uplift and exhumation are important factors affecting the preservation of deposits. The anatomy of uplift‐cooling evolution and exhumation in the East Longshou Mountain is of significant research ...value in understanding changes in the Jinchuan Ni‐Cu‐PGE deposit since its formation. This study uses apatite fission track (AFT) thermochronology to reconstruct the thermal history of the East Longshou Mountain, including the Jinchuan mine, revealing the uplift and exhumation history of the East Longshou Mountain and elucidating the preservation status of the Jinchuan deposit. The AFT ages in the East Longshou Mountain are distributed from 62.3 ± 3.0 Ma to 214.7 ± 14 Ma, with significant differences in ages in distinct areas, the central and pooled ages being consistent within the margin of error. Inverse thermal history models reveal two rapid cooling events associated with exhumation from the Early Jurassic to the Early Cretaceous (200–100 Ma) and since the Miocene (15–0 Ma), the former attributable to the far‐afield response to the closure of the Paleo‐Tethys Ocean and plate assembly at the southern margin of Eurasia, the latter associated with the initial India‐Eurasia plate collision. A slow cooling event from the Early Cretaceous to the Miocene (100–15 Ma) is thought to be related to the arid environment in northwest China since the Cretaceous. These cooling events have diverse responses and cooling rates in different blocks of the East Longshou Mountain: the southwest and centre of which are mainly cooled over 200–120 Ma and 120–0 Ma, with cooling rates of ~0.25 and ~0.33 °C/Ma (~1.25 and ~0.33 °C/Ma in the centre); the Jinchuan mine primarily cooled over 160–100 Ma, 100–15 Ma and 15–0 Ma, with cooling rates of ~1.33, ~0.25 and ~2.00 °C/Ma. These differentiated coolings imply that the uplift of the East Longshou Mountain before the Miocene (~15 Ma) was integral. Strong uplift then occurred in the vicinity of the mining area, which is a critical period for the uplift of the Jinchuan deposit to the surface, meaning that the Jinchuan deposit was exposed no earlier than the Miocene (~15 Ma). Based on mineralization depth information obtained by previous researchers, in conjunction with the calculation and simulation results of this study, it can be seen that the bulk of the Jinchuan intrusion may still be preserved at depth.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The heterostructure consisting of lead chalcogenide and halide perovskite materials are recently identified as excellent candidates for optoelectronic devices such as solar cells. Several theoretical ...works are carried out to understand the nanoscopic structures and properties of halide perovskite/lead chalcogenide heterostructures. However, the detailed features of the heterosystems, including the effects of the solute concentration, types of lead chalcogenide, and polaronic states are not investigated. In this manuscript, we employ first-principles calculations to provide an alternative view of the halide perovskite/lead chalcogenide heterostructure, focusing on CsPbI
3
and the molecular size of PbS/PbSe lead chalcogenide. The calculations confirm the constituent concentration and the elemental substitution can be employed to fine tune the optoelectronic properties of halide perovskite/lead chalcogenide heterostructures. This work facilitates the fundamental understanding of the halide perovskite/lead chalcogenide systems toward optoelectronic applications.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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