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Fast radio bursts (FRBs) are cosmological radio transients with millisecond durations and extremely high brightness temperatures. One FRB repeater, FRB 180916.J0158+65 (FRB 180916B), was confirmed to appear 16.35-day periodic activities with 5-day activity window. Another FRB repeater, FRB 121102, and two soft gamma-ray repeaters (SGRs), SGR 1935+2154 and SGR 1806−20, also show possible periodic activities. These periodicities might originate from the precession process of young magnetars due to the anisotropic pressure from the inner magnetic fields as proposed in the literature. In this work, we analyse a self-consistent model for the rotation evolution of magnetars and obtain the evolutions of magnetar precession and obliquity. We find that if the FRB repeaters and the SGRs with (possible) periodic activities originate from the magnetar precession, their ages would be constrained to be hundreds to tens of thousands of years, which is consistent with the typical ages of magnetars. Assuming that the FRB emission is beaming in the magnetosphere as proposed in the literature, we calculate the evolution of the observable probability and the duty cycle of the active window period. We find that for a given magnetar the observable probability increases with the magnetar age in the early stage and decreases with the magnetar age in the later stage; meanwhile, there are one or two active windows in one precession period if the emission is not perfectly axisymmetric with respect to the deformation axis of a magnetar, which could be tested by the future observation for repeating FRB sources. [ABSTRACT FROM AUTHOR]

The gas sensitivity of the W defect in WS2 (VW/WS2) to five toxic gases—HCHO, CH4, CH3HO, CH3OH, and CH3CH3—has been examined in this article. These five gases were adsorbed on the VW/WS2 surface, and the band, density of state (DOS), charge density difference (CDD), work function (W), current–voltage (I–V) characteristic, and sensitivity of adsorption systems were determined. Interestingly, for HCHO-VW/WS2, the energy level contribution of HCHO is closer to the Fermi level, the charge transfer (B) is the largest (0.104 e), the increase in W is more obvious than other adsorption systems, the slope of the I–V characteristic changes more obviously, and the calculated sensitivity is the highest. To sum up, VW/WS2 is more sensitive to HCHO. In conclusion, VW/WS2 has a great deal of promise for producing HCHO chemical sensors due to its high sensitivity and selectivity for HCHO, which can aid in the precise and efficient detection of toxic gases. [ABSTRACT FROM AUTHOR]

Aim: Pathologists are currently supposed to be aware of both domestic and international guidelines for breast cancer diagnosis, but it is unclear how successfully these guidelines have been integrated into routine clinical practice in China. Thus, this national proficiency testing (PT) scheme for breast pathology was set up to conduct a baseline assessment of the diagnostic capability of pathologists in China. Methods: This national PT plan is designed and implemented according to the "Conformity assessment—General requirements for proficiency testing" (GB/T27043—2012/ISO/IEC 17043:2010). Five cases of breast cancer with six key items, including histologic type, grade, ER, PR, HER2, and Ki67, were selected for testing among 96 participants. The final PT results were published on the website of the National Quality Control Center for Cancer (http://117.133.40.88:3927/cn/col22/362). Results: Our study demonstrated that the median PT score was 89.5 (54–100). Two institutions with scores < 67 were deemed unacceptable. The accuracy of histologic type, ER, PR, HER2, and Ki67 was satisfactory (all > 86%). However, the histologic grade showed low accuracy (74.0%). The unacceptable results mainly included incorrect evaluation of histologic grade (36.7%), inaccurate evaluation of ER/PR/HER2/Ki67 (28.2%), incorrect identification of C-AD as IBC-NST (15.7%), inappropriate use of 1+/2+/3+ rather than staining percentage for ER/PR (6.1%), misclassification of ER/PR < 1% weak expression as positive staining (1.4%), and no evaluation of histologic grade in ILC, MC, and IMC (5.8%). Conclusions: our nationwide PT program exhibited a satisfactory baseline assessment of the diagnostic capability of pathologists in China. More importantly, we identify some areas for further improvement. [ABSTRACT FROM AUTHOR]

Continuous visbreaking of heavy oil in a tubular reactor was studied under pressurized steam environments at 10 MPa (MPS) and 18 MPa (HPS). Within the operating range considered, heavy oil and pressurized steam exhibit a liquid-vapor two-phase structure. During the transition from the MPS environment to the HPS environment, the dissolution of water into the oil phase is promoted, thereby reducing the viscosity of the oil phase. According to the lumped reaction kinetics analysis, the reaction behavior of the lumped component VR2 with a boiling point higher than 700 °C determines the visbreaking efficiency in the early visbreaking stage to a large extent. Dealkylation of VR2 and condensation of the lightest lumped component show sensitive responses to improved diffusion in the oil phase. At 400 °C and a space time of 37 min, visbreaking in HPS environment can achieve a viscosity reduction rate of 90%. Meanwhile, the asphaltene content of the product is lower than the feedstock value. • Continuous heavy oil visbreaking was investigated in pressurized steam environments. • Visbreaking products with reduced viscosity and asphaltene content can be obtained. • Dissolution of water in heavy oil reduces the viscosity of the oil phase. • Reaction kinetics of visbreaking respond sensitively to diffusion improvement. • Dealkylation of heaviest components determines initial visbreaking efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni 2 P/Al 2 O 3 with small nanoparticles and pure phase was controllably synthesized. • Ni 2 P/Al 2 O 3 shows excellent hydrogenation and desulfurization activities. • Nanoflower-like structure improves dispersion and accessibility of active sites. • The outstanding performance can be attributed to the rich Niδ+ active sites. The hydrogenation of unsaturated bonds and elimination of sulfur impurities in C 9 petroleum resin (C 9 PR) are crucial for improving its quality and performance. In this study, we prepared a nanoflower-like Ni 2 P/Al 2 O 3 catalyst using an in-situ synthesis combined with liquid-phase phosphidation strategy and applied for the production of value-added hydrogenated C 9 PR. In-situ synthesis of Ni-Al hydrotalcite anchors and disperses Ni nanoparticles, while liquid-phase phosphidation introduces high-content Niδ+ and Pδ− active sites and prevents the formation of inactive AlPO 4 , synergistically enhancing both hydrogenation and desulfurization activities. The synthesized Ni 2 P/Al 2 O 3 catalyst achieves a 99.6 % hydrogenation degree and reduces sulfur content from 137 ppm to 0 ppm, much better than the catalysts prepared by conventional impregnation and metal phosphate reduction methods. These results give valuable insights for designing efficient catalysts and advancing single-step hydrorefining processes to generate high-quality, value-added hydrogenated petroleum resins. [ABSTRACT FROM AUTHOR]

Carbon adsorbents have been widely used to remove indoor volatile organic compounds (VOCs), however, the proliferation of bacteria on the carbon adsorbents may deteriorate the indoor air quality and thus pose a serious threat to human health. Herein, we report the synthesis of antibacterial porous carbon spheres (carbonized aminophenol-formaldehyde resin, CAF) with well-dispersed Cu species via an in situ incorporation of Cu2+ during the polymerization of 3-aminophenol-formaldehyde resin followed by a thermal carbonization and reduction process. Compared with CAF, the Cu/CAF- x nanocomposites with Cu loading show a much higher specific surface area (>700 m2 g−1 vs. 569 m2 g−1 for CAF). In addition, the pore size of Cu/CAF- x is ranging from 0.7 to 1.68 nm, which is exactly conducive to adsorb the toluene molecules. As a result, the toluene adsorption capacity is improved from 123.50 mg g−1 for CAF to >170 mg g−1 for Cu/CAF- x. More importantly, such adsorbents possess excellent antibacterial performance, the Cu/CAF-10 (10 wt% of Cu loading) with a concentration of 50 μg mL−1 can completely kill the E. coli within 30 min. Our work paves the way to the development of bifunctional adsorbents with both efficient VOCs adsorption and excellent antibacterial performance. [Display omitted] • An in situ complexation strategy is developed to prepare Cu loaded carbon composite. • Cu/CAF- x show higher toluene adsorption capacity than porous carbon adsorbent. • Cu/CAF-10 with a low concentration of 50 μg mL-1 can kill 100% E. coli within 30 min. • The in situ complexation strategy can be extended to prepare other metal-carbon composites. [ABSTRACT FROM AUTHOR]

With the increasing application of crop straw, the greenhouse gas emissions caused due to crop straw have received increasing attention. However, the current studies have not explored the greenhouse gas emissions from on-farmland consumption of returned straw. Based on a long-term positioning experiment, three treatments were set up in double-cropping rice fields: chemical fertilizer (CF), straw replacing 1/3 nitrogen fertilizer (MS), and straw replacing 2/3 nitrogen fertilizer (HS). We measured the biomass, soil properties, and greenhouse gas emissions of double-cropping rice and then comprehensively evaluated the global warming potential, carbon footprint, and net ecological and economic benefits. The straw treatments (MS and HS) increased the cumulative annual emissions of CH 4 (98.44% and 261.23%), CO 2 (30.85% and 122.29%), and N 2 O (7.37% and 52.50%), the cumulative annual global warming potential (74.15% and 206.12%), average GHG intensity (43.26% and 138.07%), and the annual cumulative net ecosystem carbon budget (52.96% and 100.97%) in the early and late rice growing seasons, respectively. We observed that the real-time greenhouse gas emissions were significantly correlated to the soil microbial functional genes and total carbon, NH 4 +-N, and NO 3 −-N. The results of the random forest model showed that total carbon (13.87%) and nirK abundance (9.80%) were the highest predictors of global warming potential at the booting and maturity stages, respectively during rice growing season. Combining the resource inputs for agricultural production and the greenhouse gas emission potential of the returned straw on its own, MS showed the lowest net greenhouse gas emission, and MS and HS showed significantly increased annual cumulative net ecological economic benefits (38.08% and 34.30%). Overall, MS showed the lowest net greenhouse gas emission and the highest net ecological economic benefits, which is a straw-returning measure with low environmental impact and high economic returns. [Display omitted] • The straw replacing chemical fertilizers increased greenhouse gas emissions. • Straw treatments increased global warming potential and greenhouse gas intensity. • Straw replaced 1/3 nitrogen fertilizer had the lowest net greenhouse gas emissions. • Straw treatments have higher rice yield and agricultural economic benefits. • Straw treatments have higher net ecological economic benefits. [ABSTRACT FROM AUTHOR]