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The large length of silicon nanowires (SiNWs) leads to their good optical properties, which causes increasing losses in the electrical performance of solar cells. The SiNWs in PEDOT:PSS/Si hybrid solar cells were optimized by simulations and experiments, and the effects of surface recombination rate and series resistance caused by SiNWs length on the performance of solar cells were studied. The results show that with the increase of SiNWs length, the surface recombination mainly affects the open circuit voltage and has great influence on the performance of solar cells. Moreover, the series resistance mainly affects the filling factor and has little effect on the performance of solar cells. Experiments show that when the length of SiNWs is about 246 nm, the highest conversion efficiency (12.88%) of PEDOT:PSS/Si hybrid solar cells can be obtained. The research results can provide guidance for the design of Si-based solar cells with SiNWs.

As the wave of industrial intelligence (AI) swept, the demographic dividend era in the Chinese labor market continued to decrease. This study aimed to explore how AI reshaped the labor employment structure of the floating population. Additionally, it clarified the internal mechanism of AI on the employment structure of the floating population based on the existing AI model and the theoretical model of AI technology. At the same time, the workforce was divided into high-, medium-, and low-skilled groups according to education level. Empirical analysis was conducted using relevant data from 31 Chinese provinces spanning from 2012 to 2018. The aim was to test the impact of AI technology on the employment of different types of floating populations. The results indicated that: (1) industrial robots impacted heterogeneous skilled floating population labor by bipolar promotion and central substitution. (2) The application of industrial robots had a promotion effect on unfinished school and primary school groups, a substitution effect on middle school, high school/technical secondary school, and college specialties, and a promotion effect on college undergraduate and graduate students. (3) Distinguish employment status, industrial robot application had a significant negative impact on low-skilled employees and significant positive effects on high-skilled employers. Hence, it was recommended to put forward corresponding policy suggestions to address this issue.

The efficient and comprehensive utilization of solar energy is of great significance for the sustainable development of energy and the realization of the strategic objectives of peak carbon dioxide emissions and carbon neutralization. Firstly, focus on the two main solar energy utilization modes, photovoltaic and photothermal, we systematically introduced the main types, research status and development trend of photovoltaic technologies, as well as the current situation and development trend of thermal power generation, building heating and refrigeration, seawater desalination and industrial heating in photothermal utilization. Then, we discussed the basic principles, main types and research progress of photovoltaic/thermal integration technology, especially the integration technology combined with the phase change heat transfer mode, was systematically introduced. Finally, several flexible "photovoltaic +" solar energy utilization technologies were introduced briefly. Photovoltaic, photothermal, photovoltaic/thermal integration and "photovoltaic +" technologies are still in a period of rapid development, have huge application potential and breed a large number of new technological growth points. These technologies are of great significance to solve the energy and environmental crisis and maintain the sustainable development of human society.

The mammalian early embryo development requires translation of maternal mRNA inherited from the oocyte. While poly(A) tail length influences mRNA translation efficiency during the oocyte-to-embryo transition (OET), molecular mechanisms regulating maternal RNA poly(A) tail length are not fully understood. In this study, we identified MARTRE, a previously uncharacterized protein family (MARTRE1-MARTRE6), as regulators expressed during mouse OET that modulate poly(A) tail length. MARTRE inhibits deadenylation through the direct interaction with the deadenylase CCR4-NOT, and ectopic expression of Martre stabilized mRNA by attenuating poly(A) tail shortening. Deletion of the Martre gene locus results in shortened poly(A) tails and decreased translation efficiency of actively translated mRNAs in mouse zygotes, but does not affect maternal mRNA decay. MARTRE proteins thus fine-tune maternal mRNA translation by negatively regulating the deadenylating activity of CCR4-NOT. Moreover, Martre knockout embryos show delayed 2-cell stage progression and compromised preimplantation development. Together, our findings highlight protection of long poly(A) tails from active deadenylation as an important mechanism to coordinate translation of maternal mRNA. This study identifies a family of protein, MARTRE, as regulators of poly(A) tail length in early mouse embryos. MARTREs inhibit CCR4-NOT complex-mediated deadenylation, ensuring efficient translation of maternal mRNA for embryo development. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are considered one of the most important solutions for energy storage; however, conventional graphite anodes possess limited specific capacity and rate capability. Bismuth sulfide (Bi2S3) and cobalt sulfide (Co1−xS) with higher theoretical capacities have emerged as promising alternatives, but they face challenges such as significant volume expansion during electrochemical cycling and poor electrical conductivity. To tackle these problems, vanadium was doped into Bi2S3 to improve its electronic conductivity; subsequently, a vanadium-doped Bi2S3 (V-Bi2S3)@Co1−xS heterojunction structure was synthesized via a facile hydrothermal method to mitigate volume expansion by the closely bonded heterojunction interface. Moreover, the built-in electric field (BEF) created at the heterointerfaces can significantly enhance charge transport and facilitate reaction kinetics. Additionally, the nanofiber morphology of the V-Bi2S3@Co1−xS heterojunction structure further contributed to improved electrochemical performance. As a result, the V-Bi2S3 electrode exhibited better electrochemical performance than the pure Bi2S3 electrode, and the V-Bi2S3@Co1−xS electrode showed a significantly enhanced performance compared to the V-Bi2S3 electrode. The V-Bi2S3@Co1−xS heterojunction electrode displayed a high capacity of 412.5 mAh g−1 after 2000 cycles at 1.0 A g−1 with high coulombic efficiencies of ~100%, indicating a remarkable long-term cycling stability. [ABSTRACT FROM AUTHOR]

Hot-spot generation is critical to the performance and lifespan of photovoltaic (PV) modules; however, the underlying mechanisms of hot-spot formation have not been fully elucidated. This work conducted a localized shading test on a PV module, measured the micro-electrical characteristics and temperature distributions of both the shaded and unshaded cells, calculated the heat-source power densities, and then predicted the occurrence and locations of hot and cold spots via numerical simulations. It was found that, under an irradiance of 750 W/m2, when one cell in a PV module is shaded by 1/2, the unshaded area within the shaded cell exhibited a hot spot, with the temperature reaching up to 77.66 °C, approximately 22.5 °C higher than the surrounding cells. The intrinsic mechanism for the occurrence of the hot spot is that, compared with the unshaded cells, the unshaded portion of the shaded cell can generate an extra significantly large Joule heat power density, about 1079.62 W/m2. The reason for generating such a large Joule heat power density is that this portion is in a reverse-bias state with a high current density flowing through it, according to our measurements. In contrast, the shaded portion forms a cold spot, about 7.5 °C cooler than the surrounding cells. This is because the shaded portion can only generate a Joule heat power density of about 46.98 W/m2 due to the small reverse-bias current density flowing through it and fails to absorb heat from solar irradiance, which is about 645 W/m2. Moreover, this work demonstrates that the hot-spot temperature initially rises and then decreases with increasing shading ratio, with the highest temperatures and the most pronounced temperature changes occurring around a shading ratio of 1/2. The presented method can be also used to evaluate the performance and reliability of various other PV modules under local shading conditions. [ABSTRACT FROM AUTHOR]