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[Objective] The impact of soil erosion on nutrient content and stoichiometric ratios in soil is crucial for further comprehending and effective control of quality degradation in the sloping farmlands of black soil regions. [Methods] Selecting straight slopes cultivated for over a century and a convex slope cultivated for more than five decades in the typical black soil area of Keshan County as the research objects, utilizing 137Cs tracing method to estimate soil erosion rates on the slopes. Quantitative analysis was conducted on the relationship between soil erosion and key parameters such as soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents, along with the stoichiometric ratio in the ecological chemistry. [Results] (1) Using 137Cs tracing technique, the average annual erosion rate of the whole slope was 4 428.56 t/(km2·a), the average erosion rates of the linear and convex slopes were 3 284.53, 5 884.59 t/(km2·a), and the total erosion volumes were calculated at 3.21×105, 2.94×105 t/km2, respectively. (2) The overall carbon/nitrogen ratio (C/N) on the slopes showed a highly significant positive correlation with SOC (p0.05). [Conclusion] Ultimately, soil erosion redistributed SOC, TN and TP on the slopes, affecting the stoichiometric ratios of soil nutrients and leading to substantial nutrient loss on the slopes.

Poly (3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is one of the most widely used functional materials for hole transport layer in perovskite light‐emitting diode (LED). Tuning its work function (WF) and conductivity (κ) is a key issue for promoting perovskite LED performance. While decreasing its WF always reduces its κ and vice versa. Solving such contradiction is quite significant for promoting the development and commercialization of perovskite LED. Herein, the aniline (Ani) is employed for PEDOT:PSS interface modification. Ani inserted between PEDOT and PSS to weaken electrostatic interaction between sulfonic acid group in PSS chain and thiophene group in PEDOT chain, which results in increased delocalized electrons to enhance its κ. More importantly, the acid–base reaction decreases high acidity of PEDOT:PSS, which is an effective way to increase its WF and decrease its interface defects density. Meanwhile, such interface modification avoids PEDOT:PSS phase separation and ensures the uniformity of film. After Ani modification, the WF of PEDOT:PSS increase from 5.16 to 5.31 eV, the κ increases from 0.30 to 8.62 S cm−1, and the hole mobility enhances from 0.716 × 10−6 to 1.306 × 10−6 cm2 V−1 s−1. Modified PEDOT:PSS boost CsPbI3 LED achieving a maximum external quantum efficiency of 17.70%. [ABSTRACT FROM AUTHOR]

α-CsPbI3 quantum dots (QDs) are ideal materials for pure red light-emitting diodes (LEDs) to achieve a wide color gamut display. Small α-CsPbI3 QDs have a large specific surface area and exhibit a near-spherical shape, discontinuous crystal faces with intense surface defects and crystal distortion, which accelerates phase transition and optoelectronic degradation. Additionally, the tolerance factor for α-CsPbI3 is too small to be stabilized. Herein, we report a Ca2+ doping strategy to tune the CsPbI3 tolerance factor to inhibit its phase transition, enhance its structural stability, decrease the lattice distortion and reduce the defects. The stability of the Ca2+-doped CsPbI3 QDs under harsh conditions are improved. The Commission Internationale de l'Eclairage coordinates of the perovskite LEDs are (0.706, 0.294), satisfying wide color gamut as well as Rec. 2020 requirements for pure red, and the LEDs exhibit a 1.67-fold enhancement in half-lifetime to 32.0 min at a voltage of 5.0 V (346 cd m−2) and 1.31-fold enhancement in the EQE to 10.3%. [ABSTRACT FROM AUTHOR]

This communication describes an effective morphological control strategy involving introducing two-dimensional (2D) Cs3Sb2Br9 to induce a transformation of three-dimensional (3D) CsPbBr3 to 2D nanoplates (NPLs). By tuning the Sb/Pb ratio, 2D CsPbBr3 NPLs exhibiting a deep-blue emission centered at a wavelength of 464 nm with an FWHM of 24 nm have been produced. The absence of organic ligands in these high-quality 2D NPLs mitigate the instability issue induced by organic ligand migration and penetration, and these NPLs exhibit 80% of the initial PL intensity after 55 days. [ABSTRACT FROM AUTHOR]

This communication describes a strategy to synthesize stable deep blue FAPbBr3 quantum dots (QDs) by constructing a matrix structure. Amorphous Ni2+-based metal halide matrices can stabilize QDs from both chemical and physical factors, and Ni2+ doping can further enhance their structural stability due to lattice shrinking. Such deep blue QD films exhibit stable X-ray diffraction patterns and photoluminescence even after 245 days of storage. [ABSTRACT FROM AUTHOR]

Development of high‐performance and stable pure red perovskite light‐emitting devices (LEDs) promotes commercialization of perovskite. Benefiting from the quantum confinement effect, pure red CsPbI3 quantum dots (QDs) can avoid the color drift issue for mixed halide systems. Herein, a facile temperature‐dependent hot‐injection method combined with low temperature gradient centrifugation is employed to prepare 5.60 ± 0.05 nm pure red QDs. The QDs exhibit 642 nm photoluminescence (PL) with 37 nm full width at half maximum, and their Commission Internationale de l'Eclairage (CIE) coordinates located at (0.708, 0.292) match well with standard pure red for Rec. 2020. The PL half‐lifetime for pure red QDs solution is 210 days under ambient conditions, and both the X and Y coordinates of CIE only fluctuate within (0.002, 0.002). Finally, a simple NH4I post‐treatment to decrease ligand length further boosts the QDs conductivity, and the pure red LED exhibits 9.4% maximum external quantum efficiency. The electroluminescence spectra exhibits a sharp peak at 645 nm, and their CIE coordinates are located at (0.707, 0.290). Furthermore, the pure red LED exhibits both good working and color stability. Its half‐lifetime is 25.1 min and color drifts are only (0.002, 0.002) after 30.0 min of continuous working at 60 cd m−2 with a constant current density of 3.5 mA cm−2. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to evaluate the use of percutaneous curved vertebroplasty procedure (PCVP) and bilateral-pedicle-approach percutaneous vertebroplasty (bPVP) for the treatment of osteoporotic vertebral compression fractures (OVCFs) through a systematic review and meta-analysis of the scientific literature. Methods: A systematic review of the scientific literature in PubMed, China National Knowledge Infrastructure (CNKI), Wanfang and other databases was conducted in conjunction with different keywords. Nine studies were included; all but 3 were randomised controlled studies and all were prospective or retrospective cohort studies. Results: We observed statistically significant differences between the PCVP group and the bPCVP group in terms of postoperative visual analogue scale (VAS) scores (mean difference [MD]: −.08; 95% confidence intervals [CI]: −.15 to.00), bone cement leakage rates (OR =.33; 95%CI:.20 to.54), bone cement injection (MD: −1.52; 95%CI: −1.58 to 1.45), operative times (MD: −16.69; 95%CI: −17.40 to −15.99) and intraoperative fluoroscopies (MD: −8.16; 95%CI: −9.56 to −6.67), with the PCVP group being more dominant. There were no statistical differences in postoperative Oswestry Disability Index (ODI) scores (MD: −.72; 95%CI: −2.11 to.67) and overall bone cement distribution rates (MD: 2.14; 95%CI:.99 to 4.65) between the 2 groups. Conclusions: Meta-analysis showed more favourable outcomes in the PCVP group compared to the bPVP group. PCVP might be effective and safe in the treatment of OVCFs because it relieves postoperative patient pain, reduces operative time and cement injection, and decreases the risk of cement leakage and radiation exposure to the surgeon and patient. [ABSTRACT FROM AUTHOR]

Aims: With the wide application of 7Be (Beryllium-7) in soil erosion investigations, retention and interception of 7Be by vegetation plays an important role in documenting soil 7Be redistribution, with a large impact on the interpretation of 7Be measurements. However, the dynamic and temporal changes in plants and the relationship with soil 7Be concentration remain unclear, and the significance of dead plants in 7Be interception is under-researched. Methods: The samples of single plants (6 different species), compositive plants (including living and dead plants), along with soil reference on the Loess Plateau were collected individually to analyze the variations of 7Be concentration during the growth period from 2010 to 2012. Results: The accumulation of 7Be per mass is significantly higher in leaves than stems. The 7Be activity per mass and per area in living plants with seasonal trends ranged from 173.9 to 703.1 Bq kg–1 and 21.5 to 190.1 Bq m–2, respectively, and in dead plants ranged from 381.8 to 964.5 Bq kg–1 and 30.4 to 285.7 Bq m–2. Precipitation accounted for the largest contribution to the accumulation of 7Be in plants, followed by plant growth, species and parts. Plants accounted for 7Be interception on slope up to 66% (living plants accounted for 7% ~ 31% and dead plants accounted for 6% ~ 44%). The interception of living plants is low at first, then increases with the accumulation of rainfall and biomass together. Conclusions: Our results highlight that 7Be in plants (especially for the dead plants) is of great significance for 7Be in soil on the slope, and is controlled by precipitation, growth status and plant characteristics. The reference information obtained in this work will contribute to improving the accuracy of 7Be tracing technology, and broadening its scope. [ABSTRACT FROM AUTHOR]

CsPbI 3 nanocrystals (NCs) have become a research hot spot in the field of light-emitting diodes (LEDs). Whereas, the long chain ligands with weak affinity to CsPbI 3 NCs have prevented their further development and commercialization. Herein, a novel multidentate short ligand tetramethylthiuram disulfide (TMTD) was employed via a ligand exchange process to enhance hole mobility and decrease trap density of the CsPbI 3 NCs film. Therefore, TMTD passivated CsPbI 3 NCs LED exhibited 20.65% maximum external quantum efficiency and 3861 cd/m 2 maximum luminance. Furthermore, TMTD passivated CsPbI 3 NCs LED exhibited good operational stability with a 128 min half-lifetime. This strategy using multidentate short ligand passivation provides an effective way to promote perovskite LED development and commercialization.