Research on the micro-hole texture forming of PCD tool surface

Based on the research on the forming mechanism of textured PCD tool surface, the nanosecond laser is used to study the influence of laser machining parameters on the size and topography of PCD tool surface micro texture. The micro-hole texture is prepared on the surface of the PCD tool, and a single factor experiment is designed to study the influence of laser power, pulse frequency and defocusing amount on the micro-hole texture. The results show that, the micro-hole diameter increases gradually with the laser power, but decreases with the pulse frequency; the overall micro-hole diameter tends to increase with the defocus. The pulse frequency has the greatest impact on the micro-hole diameter, followed by the defocus amount, and finally the laser power. The influence of different parameters on the surface recast layer is also completely different. As a result, the surface and laser power are the main factors that affect the surface recast layer

What Promotes Natural Forest Protection and Restoration? Insights from the Perspective of Multiple Parties

The natural forest protection and restoration (NFPR) system is imperfect due to contradictions between the objectives of natural forest protection and the reality of situations, outdated cultivation concepts, conflicting interests among participating parties, and the lack of regulation guarantees and assessment criteria. These problems are not only common in China but also in international forest protection. As the NFPR system is more focused on the protection of natural forests, the level of natural forest restoration in China has been poor, with low natural forest quality and forest productivity. At the same time, the value of natural forest ecosystem services does not match the demand of farmers, forest management, and other multiple participating parties. As a result, except for the government, other multiple parties lack the intrinsic motivation to participate in NFPR, ultimately forming a sustainable management dilemma. Under the institutional analysis and development (IAD) framework, the objective of this research was to explore the influencing factors and outcomes of the participation of multiple parties in NFPR and to construct a multiple parties’ participation mechanism for solving this dilemma. This research found that among external variables, multiple parties’ characteristics, biophysical conditions, attributes of community, and rules-in-use jointly influence and constitute the driving mechanism of multiple parties’ participation in NFPR. The rules-in-use directly impact the participation action scenario and regulate the other three external variables. Various factors and mechanisms in NFPR interact in the action space and produce outcomes that create positive incentives for each external variable, thus promoting the whole mechanism to achieve a virtuous cycle of sustainable management. This study provides a theoretical contribution to understanding the behavior of multiple parties participating in NFPR

A New Global Bathymetry Model: STO_IEU2020

To address the limitations in global seafloor topography model construction, a scheme is proposed that takes into account the efficiency of seafloor topography prediction, the applicability of inversion methods, the heterogeneity of seafloor environments, and the inversion advantages of sea surface gravity field element. Using the South China Sea as a study area, we analyzed and developed the methodology in modeling the seafloor topography, and then evaluated the feasibility and effectiveness of the modeling strategy. Based on the proposed modeling approach, the STO_IEU2020 global bathymetry model was constructed using various input data, including the SIO V29.1 gravity anomaly (GA) and vertical gravity gradient anomaly (VGG), as well as bathymetric data from multiple sources (single beam, multi-beam, seismic, Electronic Navigation Chart, and radar sensor). Five evaluation areas located in the Atlantic and Indian Oceans were used to assess the performance of the generated model. The results showed that 79%, 89%, 72%, 92% and 93% of the checkpoints were within the ±100 m range for the five evaluation areas, and with average relative accuracy better than 6%. The generated STO_IEU2020 model correlates well with the SIO V20.1 model, indicating that the proposed construction strategy for global seafloor topography is feasible

The development of Ce3+-activated (Gd,Lu)3Al5O12 garnet solid solutions as efficient yellow-emitting phosphors

Ce3+-activated Gd3Al5O12 garnet, effectively stabilized by Lu3+ doping, has been developed for new yellow-emitting phosphors. The powder processing of [(Gd1−xLux)1−yCey]3Al5O12 solid solutions was achieved through precursor synthesis via carbonate precipitation, followed by annealing. The resultant (Gd,Lu)AG:Ce3+ phosphor particles exhibit typical yellow emission at ~570 nm (5d–4f transition of Ce3+) upon blue-light excitation at ~457 nm (the 2F5/2–5d transition of Ce3+). The quenching concentration of Ce3+ was determined to be ~1.0 at% (y = 0.01) and the quenching mechanism was suggested to be driven by exchange interactions. The best luminescent [(Gd0.9Lu0.1)0.99Ce0.01]AG phosphor is comparative to the well-known YAG:Ce3+ in emission intensity but has a substantially red-shifted emission band that is desired for warm-white lighting. The effects of processing temperature (1000–1500 °C) on the spectroscopic properties of the phosphors, especially those of Lu3+/Ce3+, were thoroughly investigated and discussed from the centroid position and crystal field splitting of the Ce3+ 5d energy levels

Layered rare-earth hydroxide and oxide nanoplates of the Y/Tb/Eu system: phase-controlled processing, structure characterization and color-tunable photoluminescence via selective excitation and efficient energy transfer

Well-crystallized (Y0.97−xTb0.03Eux)2(OH)5NO3centerdotnH2O (x = 0–0.03) layered rare-earth hydroxide (LRH) nanoflakes of a pure high-hydration phase have been produced by autoclaving from the nitrate/NH4OH reaction system under the optimized conditions of 100 °C and pH ~7.0. The flakes were then converted into (Y0.97−xTb0.03Eux)2O3 phosphor nanoplates with color-tunable photoluminescence. Detailed structural characterizations confirmed that LRH solid solutions contained NO3− anions intercalated between the layers. Characteristic Tb3+ and Eu3+ emissions were detected in the ternary LRHs by selectively exciting the two types of activators, and the energy transfer from Tb3+ to Eu3+ was observed. Annealing the LRHs at 1100 °C produced cubic-lattice (Y0.97−xTb0.03Eux)2O3 solid-solution nanoplates with exposed 222 facets. Multicolor, intensity-adjustable luminescence was attained by varying the excitation wavelength from ~249 nm (the charge transfer excitation band of Eu3+) to 278 nm (the 4f8–4f75d1 transition of Tb3+). Unitizing the efficient Tb3+ to Eu3+ energy transfer, the emission color of (Y0.97−xTb0.03Eux)2O3 was tuned from approximately green to yellowish-orange by varying the Eu3+/Tb3+ ratio. At the optimal Eu3+ content of x = 0.01, the efficiency of energy transfer was ~91% and the transfer mechanism was suggested to be electric multipole interactions. The phosphor nanoplates developed in this work may be incorporated in luminescent films and find various lighting and display applications

SBP1 promotes tumorigenesis of thyroid cancer through TXN/NIS pathway

Abstract Background As the tissue with the highest selenium content in the body, the occurrence and development of thyroid cancer are closely related to selenium and selenoproteins. Selenium-binding protein 1 (SBP1) has been repeatedly implicated in several cancers, but its role and molecular mechanisms in thyroid cancer remains largely undefined. Methods The expression of SBP1, sodium/iodide symporter (NIS) and thioredoxin (TXN) were analyzed in clinical samples and cell lines. Cell counting kit-8 (CCK-8) and tube formation assays were used to analyze the cell viability and tube formation of cells. Immunofluorescence was used to determine the expression of the NIS. Co-immunoprecipitation (Co-IP) assay was carried out to verify the interaction of SBP1 with TXN. The mouse xenograft experiment was performed to investigate the growth of thyroid cancer cells with SBP1 knockdown in vivo. Results SBP1 was significantly increased in human thyroid cancer tissues and cells, especially in anaplastic thyroid cancer. Overexpression of SBP1 promoted FTC-133 cell proliferation, and the culture supernatant of SBP1-overexpression FTC-133 cells promoted tube formation of human retinal microvascular endothelial cells. Knockdown of SBP1, however, inhibited cell proliferation and tube formation. Furthermore, overexpression of SBP1 inhibited cellular differentiation of differentiated thyroid cancer cell line FTC-133, as indicated by decreased expression of thyroid stimulating hormone receptors, thyroglobulin and NIS. Knockdown of SBP1, however, promoted differentiation of BHT101 cells, an anaplastic thyroid cancer cell line. Notably, TXN, a negative regulator of NIS, was found to be significantly upregulated in human thyroid cancer tissues, and it was positively regulated by SBP1. Co-IP assay implied a direct interaction of SBP1 with TXN. Additionally, TXN overexpression reversed the effect of SBP1 knockdown on BHT101 cell viability, tube formation and cell differentiation. An in vivo study found that knockdown of SBP1 promoted the expression of thyroid stimulating hormone receptors, thyroglobulin and NIS, as well as inhibited the growth and progression of thyroid cancer tumors. Conclusion SBP1 promoted tumorigenesis and dedifferentiation of thyroid cancer through positively regulating TXN

Effective lattice stabilization of gadolinium aluminate garnet (GdAG) via Lu3+ doping and development of highly efficient (Gd,Lu)AG:Eu3+ red phosphors

The metastable garnet lattice of Gd3Al5O12 is stabilized by doping with smaller Lu3+, which then allows an effective incorporation of larger Eu3+ activators. The [(Gd1−xLux)1−yEuy]3Al5O12 (x = 0.1–0.5, y = 0.01–0.09) garnet solid solutions, calcined from their precursors synthesized via carbonate coprecipitation, exhibit strong luminescence at 591 nm (the 5D0 → 7F1 magnetic dipole transition of Eu3+) upon UV excitation into the charge transfer band (CTB) at ~239 nm, with CIE chromaticity coordinates of x = 0.620 and y = 0.380 (orange-red). The quenching concentration of Eu3+ was estimated at ~5 at.% (y = 0.05), and the quenching was attributed to exchange interactions. Partial replacement of Gd3+ with Lu3+ up to 50 at.% (x = 0.5) while keeping Eu3+ at the optimal content of 5 at.% does not significantly alter the peak positions of the CTB and 5D0 → 7F1 emission bands but slightly weakens both bands owing to the higher electronegativity of Lu3+. The effects of processing temperature (1000–1500 °C) and Lu/Eu contents on the intensity, quantum efficiency, lifetime and asymmetry factor of luminescence were thoroughly investigated. The [(Gd0.7Lu0.3)0.95Eu0.05]3Al5O12 phosphor processed at 1500 °C exhibits a high internal quantum efficiency of ~83.2% under 239 nm excitation, which, in combination with the high theoretical density, favors its use as a new type of photoluminescent and scintillation material