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The performance of perovskite photovoltaics is fundamentally impeded by the presence of undesirable defects that contribute to non-radiative losses within the devices. Although mitigating these losses has been extensively reported by numerous passivation strategies, a detailed understanding of loss origins within the devices remains elusive. Here, we demonstrate that the defect capturing probability estimated by the capture cross-section is decreased by varying the dielectric response, producing the dielectric screening effect in the perovskite. The resulting perovskites also show reduced surface recombination and a weaker electron-phonon coupling. All of these boost the power conversion efficiency to 22.3% for an inverted perovskite photovoltaic device with a high open-circuit voltage of 1.25 V and a low voltage deficit of 0.37 V (a bandgap ~1.62 eV). Our results provide not only an in-depth understanding of the carrier capture processes in perovskites, but also a promising pathway for realizing highly efficient devices via dielectric regulation. Performance of perovskite photovoltaics is greatly affected by undesirable defects that contribute to non-radiative losses. Here, the authors mitigate these losses by doping perovskite with KI to alter the dielectric response, thus defect capturing probability, resulting in inverted device with PCE of 22.3% and low voltage loss.

Plant diseases caused by plant viruses and pathogens seriously affect crop yield and quality, and it is very difficult to control them. The discovery of new leads based on natural products is an important way to innovate pesticides. Based on the resveratrol is a kind of natural phytoalexin, but it cannot be used as candidate for the development of new drug due to its poor druggability. The phenolic hydroxyl groups in the resveratrol structure are easily destroyed by oxidation, in order to improve its stability, ester formation is the most commonly used modification method in drug design. Their structures were characterized by 1 H NMR, 13 C NMR and HRMS. The activity against tobacco mosaic virus (TMV) of these ester derivatives has been tested for the first time. The bioassay results showed part of the target compounds exhibited good to excellent in vivo activities against TMV. The optimum compounds III-2 (inhibitory rates of 50, 53, and 59% at 500 μg/mL for inactivation, curative, and protection activities in vivo, respectively), III-4 (inhibitory rates of 57, 59, and 51% at 500 μg/mL, respectively), and II-5 (inhibitory rates of 54, 52, and 51% at 500 μg/mL, respectively) displayed higher activity than commercial plant virucide ribavirin (inhibitory rates of 38, 37, and 40% at 500 μg/mL, respectively). Compounds I-9 and I-10 also showed excellent activities. The systematic study provides strong evidence that these simple resveratrol derivatives could become potential TMV inhibitors. The novel concise structure provides another new template for antiviral studies.

Inverted planar perovskite solar cells offer opportunities for a simplified device structure compared with conventional mesoporous titanium oxide interlayers. However, their lower open-circuit voltages result in lower power conversion efficiencies. Using mixed-cation lead mixed-halide perovskite and a solution-processed secondary growth method, Luo et al. created a surface region in the perovskite film that inhibited nonradiative charge-carrier recombination. This kind of solar cell had comparable performance to that of conventional cells. Science , this issue p. 1442 High open-circuit voltages were achieved for planar perovskite solar cells by creating a graded junction. The highest power conversion efficiencies (PCEs) reported for perovskite solar cells (PSCs) with inverted planar structures are still inferior to those of PSCs with regular structures, mainly because of lower open-circuit voltages ( V oc ). Here we report a strategy to reduce nonradiative recombination for the inverted devices, based on a simple solution-processed secondary growth technique. This approach produces a wider bandgap top layer and a more n-type perovskite film, which mitigates nonradiative recombination, leading to an increase in V oc by up to 100 millivolts. We achieved a high V oc of 1.21 volts without sacrificing photocurrent, corresponding to a voltage deficit of 0.41 volts at a bandgap of 1.62 electron volts. This improvement led to a stabilized power output approaching 21% at the maximum power point.

Heat stress inhibits photosynthesis efficiency, thereby suppressing plant growth and crop yield. However, the mechanism underlying this inhibition is not fully understood. Here, we report that the multiple organellar RNA-editing factor 8 (MORF8) forms condensates with solid-like properties in chloroplasts upon heat stress. In vitro data show that the MORF8 condensation is intrinsically heat-dependent and primarily determined by its IDR (intrinsically disordered region). Purification and characterization of MORF8 condensates show that numerous editing factors including PPR proteins and MORFs are partitioned. We provide both genetic and biochemical evidence that MORF8 condensation inhibits chloroplast RNA editing. In agreement, we find that both heat stress and MORF8 condensation lead to reduced editing of RNAs encoding NADH dehydrogenase-like (NDH) complex and impaired NDH activity and photosynthesis efficiency. These findings uncover MORF8 as a putative chloroplastic thermosensor that mediates photosynthesis inhibition by heat and highlight the functional significance of solid material properties of biomolecular condensates. How plants perceive and respond to heat stress via chloroplast is obscure. Here, the authors present evidence that an RNA editing component undergoes heat-dependent condensation, which in turn inhibits RNA editing and photosynthesis efficiency.

Electrocatalytic NO reduction reaction (NORR) offers a promising route for sustainable NH 3 synthesis along with removal of NO pollutant. However, it remains a great challenge to accomplish both high NH 3 production rate and long duration to satisfy industrial application demands. Here, we report an in situ-formed hierarchical porous Cu nanowire array monolithic electrode ensembled in a pressurized electrolyzer to regulate NORR reaction kinetics and thermodynamics, which delivers an industrial-level NH 3 partial current density of 1007 mA cm –2 with Faradaic efficiency of 96.1% and remains stable at 1000 mA cm –2 for 100 hours. Integrating the Cu nanowire array monolithic electrode with pressurized electrolyzer boosts the NH 3 production rate to 10.5 mmol h –1 cm –2 , which is over tenfold that using commercial Cu foam at 1 atm. The NORR performance can be attributed to the promoted NO mass transfer to the enriched Cu surface, which could increase the NO coverage on Cu and then destabilize adsorbed NO and weaken hydrogen adsorption, thereby facilitating NO hydrogenation to NH 3 while suppressing the competing hydrogen evolution. The electrocatalytic NO reduction reaction enables sustainable NH 3 synthesis and NO removal but faces challenges in achieving industrial-level efficiency and durability. Here the authors present an in situ-formed copper nanowire array monolithic electrode integrated into a pressurized electrolyzer for stable ammonia electrosynthesis at around 1000 mA cm –2 for 100 h.

Natural enzymes feature distinctive second spheres near their active sites, leading to exquisite catalytic reactivity. However, incumbent synthetic strategies offer limited versatility in functionalizing the second spheres of heterogeneous catalysts. Here, we prepare an enzyme-mimetic single Co–N 4 atom catalyst with an elaborately configured pendant amine group in the second sphere via 1,3-dipolar cycloaddition, which switches the oxygen reduction reaction selectivity from the 4e − to the 2e − pathway under acidic conditions. Proton inventory studies and theoretical calculations reveal that the introduced pendant amine acts as a proton relay and promotes the protonation of *O 2 to *OOH on the Co–N 4 active site, facilitating H 2 O 2 production. The second sphere-tailored Co–N 4 sites reach optima H 2 O 2 selectivity of 97% ± 1.13%, showing a 3.46-fold enhancement to bare Co–N 4 catalyst (28% ± 1.75%). This work provides an appealed approach for enzyme-like catalyst design, bridging the gap between enzymatic and heterogeneous catalysis. Here, the authors present a Co-N4 single-atom catalyst with pendant amine group in the second sphere, which shifts the oxygen reduction reaction selectivity toward hydrogen peroxide production.

In low-permeability fractured reservoirs, there is a generalized fluid displacement between the replacement fluid in the fracture and the matrix crude oil. This imbibition behavior plays a crucial role in the development of this type of reservoir. The experimental devices for studying static imbibition behavior are generally susceptible to air pollution on the surface of the test core and a long testing period; the experimental devices for studying dynamic imbibition behavior are generally unable to eliminate the driving action. A dual-purpose experimental setup and an experimental method for dynamic or static imbibition that can avoid the above defects were designed. A method of fracture fluid flow rate calculation and motor speed conversion is proposed, and the method is used to assist in setting the parameters of dynamic imbibition experiments. The device was applied to compare the experimental effects with the static imbibition bottle and the dynamic replacement imbibition, respectively, and the effect of fracture width on the dynamic imbibition of repellent oil was investigated. The results show that: the static imbibition recovery rate of the dynamic/static imbibition experimental device is 1.55 percentage points higher than that of the imbibition bottle; the dynamic imbibition recovery rate is 3–6 percentage points lower than that of the driving dynamic imbibition method, and it can reflect the influence of a single flow rate condition on the imbibition; imbibition in low-permeability fractured reservoirs is more likely to take place in the fracture in the interval of 50–100 μm in the width.

Four episodes of granitic rocks at 517, 501-496, 462-451, and 426-385 Ma occurred in the South Altyn subduction-collision complex. The first episode of granite emplacement predates the formation of the ophiolite type mafic rock （〉500 Ma）, and the three subsequent episodes can be temporally correlated to high-pressure （HP） to ultrahigh-pressure （UHP） metamorphism at ca 500 Ma, retrograde granulite-facies metamorphism at ca. 450 Ma, and amphibolite-facies metamorphism at ca. 420 Ma, re- spectively. A comprehensive study of these granitic rocks, along with the regional geological background, mafic-ultramafic rocks, and HP-UHP metamorphism, indicates that the four episodes of granitic magmatism are sequentially derived from the partial melting of the earlier subducted oceanic crust at 517 Ma, the thickened continental crust due to continental subduction at ca. 500 Ma, the mid-upper crust in response to slab breakoff at ca. 450 Ma, and the tectonic transition from contraction to extension at ca. 420 Ma. The formation age of 517 Ma for oceanic adakite provides a direct constraint on the time of the oce- anic subduction in South Altyn. In addition, there is a ca. i0 Myr interval between the oceanic subduction to the continental deep subduction, suggesting that the Early Paleozoic tectonic evolution might have been a successive process in South Altyn. The four episodes of formation of granitic rocks, mafic-ultramafic rocks, and HP-UHP metamorphic rocks have fully recorded the tectonic evolution, beginning with the oceanic subduction, followed by continental subduction, and later exhumation dur- ing the Early Paleozoic in South Altyn.

The dynamic economic dispatch (DED) problem is a typical complex constrained optimization problem with non-smooth, nonlinear, and nonconvex characteristics, especially considering practical situations such as valve point effects and transmission losses, and its objective is to minimize the total fuel costs and total carbon emissions of generating units during the dispatch cycle while satisfying a series of equality and inequality constraints. For the challenging DED problem, a model of a dynamic economic dispatch problem considering fuel costs is first established, and then an improved grey wolf optimization algorithm (IGWO) is proposed, in which the exploitation and exploration capability of the original grey wolf optimization algorithm (GWO) is enhanced by initializing the population with a chaotic algorithm and introducing a nonlinear convergence factor to improve weights. Furthermore, a simple and effective constraint-handling method is proposed for the infeasible solutions. The performance of the IGWO is tested with eight benchmark functions selected and compared with other commonly used algorithms. Finally, the IGWO is utilized for three different scales of DED cases, and compared with existing methods in the literature. The results show that the proposed IGWO has a faster convergence rate and better global optimization capabilities, and effectively reduces the fuel costs of the units, thus proving the effectiveness of IGWO.

Aedes albopictus is one of the most invasive species in the world as well as the important vector for mosquito-borne diseases such as dengue fever, chikungunya fever and zika virus disease. Chemical control of mosquitoes is an effective method to control mosquito-borne diseases, however, the wide and improper application of insecticides for vector control has led to serious resistance problems. At present, there have been many reports on the resistance to pyrethroid insecticides in vector mosquitoes including deltamethrin to Aedes albopictus. However, the fitness cost and vector competence of deltamethrin resistant Aedes albopictus remain unknown. To understand the impact of insecticide resistant mosquito is of great significance for the prevention and control mosquitoes and mosquito-borne diseases. A laboratory resistant strain (Lab-R) of Aedes albopictus was established by deltamethrin insecticide selecting from the laboratory susceptible strain (Lab-S). The life table between the two strains were comparatively analyzed. The average development time of Lab-R and Lab-S in larvae was 9.7 days and 8.2 days (P < 0.005), and in pupae was 2.0 days and 1.8 days respectively (P > 0.05), indicating that deltamethrin resistance prolongs the larval development time of resistant mosquitoes. The average survival time of resistant adults was significantly shorter than that of susceptible adults, while the body weight of resistant female adults was significantly higher than that of the susceptible females. We also compared the vector competence for dengue virus type-2 (DENV-2) between the two strains via RT-qPCR. Considering the results of infection rate (IR) and virus load, there was no difference between the two strains during the early period of infection (4, 7, 10 day post infection (dpi)). However, in the later period of infection (14 dpi), IR and virus load in heads, salivary glands and ovaries of the resistant mosquitoes were significantly lower than those of the susceptible strain (IR of heads, salivary glands and ovaries: P < 0.05; virus load in heads and salivary glands: P < 0.05; virus load in ovaries: P < 0.001). And then, fourteen days after the DENV-2-infectious blood meal, females of the susceptible and resistant strains were allow to bite 5-day-old suckling mice. Both stains of mosquito can transmit DENV-2 to mice, but the onset of viremia was later in the mice biting by resistant group as well as lower virus copies in serum and brains, suggesting that the horizontal transmission of the resistant strain is lower than the susceptible strain. Meanwhile, we also detected IR of egg pools of the two strains on 14 dpi and found that the resistant strain were less capable of vertical transmission than susceptible mosquitoes. In addition, the average survival time of the resistant females infected with DENV-2 was 16 days, which was the shortest among the four groups of female mosquitoes, suggesting that deltamethrin resistance would shorten the life span of female Aedes albopictus infected with DENV-2. As Aedes albopictus developing high resistance to deltamethrin, the resistance prolonged the growth and development of larvae, shorten the life span of adults, as well as reduced the vector competence of resistant Aedes albopictus for DENV-2. It can be concluded that the resistance to deltamethrin in Aedes albopictus is a double-edged sword, which not only endow the mosquito survive under the pressure of insecticide, but also increase the fitness cost and decrease its vector competence. However, Aedes albopictus resistant to deltamethrin can still complete the external incubation period and transmit dengue virus, which remains a potential vector for dengue virus transmission and becomes a threat to public health. Therefore, we should pay high attention for the problem of insecticide resistance so that to better prevent and control mosquito-borne diseases.