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Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), we have recorded over 1.2 × 104 single pulses from PSR B0823+26 (J0826+2637) at 1.25 GHz with 500 MHz bandwidth. These high-sensitivity observations detected with FAST are unprecedented. We investigated potentially interesting emission features by analyzing the polarimetric individual pulses during the bright state. The average pulse profile has a weak postcursor component and a wide interpulse along with a narrow main pulse. The pulse energy distribution of the main pulse shows the presence of triple emission modes. When the emission ceases in the main pulse component, low-level emission in the interpulse component is detected, whereas the absence of any emission in the postcursor component is shown. In the postcursor emission region, bright pulses are detected in 422 rotations with the relative pulse energy described by a power-law distribution with index of −2.52 ± 0.09, while the peak flux density ratio appears to follow a logarithmic normal distribution. The intervals between bright pulses can be described with a Poisson process with the occurrence rate estimated to be one bright pulse every 14 s. The fluctuation spectral analysis reveals the existence of a form of periodic amplitude modulation unrelated to subpulse drifting in both the main pulse and interpulse components. Furthermore, the modulation patterns in the main pulse and interpulse are found to be locked in pulse longitude, signifying some information transfer between the two magnetic polar regions. [ABSTRACT FROM AUTHOR]

We report the phase-connected timing ephemeris, polarization pulse profiles, Faraday rotation measurements, and Rotating-Vector-Model (RVM) fitting results of 12 millisecond pulsars (MSPs) discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in the Commensal Radio Astronomy FAST survey (CRAFTS). The timing campaigns were carried out with FAST and Arecibo over 3 yr. 11 of the 12 pulsars are in neutron star–white dwarf binary systems, with orbital periods between 2.4 and 100 d. 10 of them have spin periods, companion masses, and orbital eccentricities that are consistent with the theoretical expectations for MSP–Helium white dwarf (He WD) systems. The last binary pulsar (PSR J1912−0952) has a significantly smaller spin frequency and a smaller companion mass, the latter could be caused by a low orbital inclination for the system. Its orbital period of 29 d is well within the range of orbital periods where some MSP–He WD systems have shown anomalous eccentricities, however, the eccentricity of PSR J1912−0952 is typical of what one finds for the remaining MSP–He WD systems. [ABSTRACT FROM AUTHOR]

Abstract: Empirical estimation is a common method for getting mode I fracture toughness KIC of rock. By collecting data from tests in this study and literature, 204 sets of KIC and tensile strength σt test data are obtained for new empirical KIC‐σt relations regression. The empirical relations make the estimation of KIC values from σt conveniently, but test procedures and lithology will influence its reasonability and reliability. Results indicate that the empirical KIC‐σt relations obtained from the four different suggested KIC test methods are all in good but obviously different linear relationship. The analyses show that cracked chevron notch Brazilian disc specimen (CCNBD) test‐based empirical relation is more accurate for estimating KIC than the other three test‐based empirical relations. As to different lithology, isotropic rocks such as sandstone and carbonatite may be more appropriate for the application of empirical estimation method. However, for coarse grained or anisotropic rocks such as granite and marble, estimation method should be applied carefully because of possibly weak KIC‐σt relations. [ABSTRACT FROM AUTHOR]

The polarization of light can provide abundant information regarding the polarization degree, phase shift, and Jones vector, which is important in light communication, environmental scanning, quality inspection, etc. Recently, two-dimensional (2D) semiconductors have provided an ideal platform for detecting polarized light due to their remarkable and tunable linear dichroism (LD). However, the physical mechanism of the in-plane LD in 2D semiconductors has not been systematically investigated, limiting the further exploration of the 2D anisotropic semiconductors and the directionality of experiments on polarization photodetection. In this study, the in-plane LD of 100 types of 2D semiconductors composed of main group elements is investigated via first-principles theory combined with the decision tree algorithm and experimental measurement. The in-plane asymmetry of the lattice and band edge wavefunctions are the main origins of the in-plane LD. 2D semiconductors with in-plane orthorhombic and monoclinic lattices tend to have considerable in-plane LD, while their hexagonal counterparts are optically isotropic. Specifically, orthorhombic 2D semiconductors possess larger in-plane LD because their intrinsic mirror planes in the lattice induce in-plane parity of the wavefunctions at the band edges. The decision tree algorithm further reveals that in-plane LD is also related to the difference for the a and b lattice constants and the electronegativity difference between the cation and anion. In addition, heterostructures formed from these 2D semiconductors exhibit high light absorption, strong in-plane LD, and various types of band alignment. The result of our study can promote the application and development of 2D semiconductors in polarization optoelectronics. [ABSTRACT FROM AUTHOR]

The origin of an extraordinary X-ray burst (XRB) associated with a fast radio burst (FRB) such as FRB 20200428 is still unclear, though several models, such as the emission of a trapped fireball modified by resonant cyclotron scattering, the outflow from a polar trapped-expanding fireball, and the synchrotron radiation of a far-away relativistic shock, have been proposed. To determine which model is true, we study the possible X-ray polarization signature for each model, inspired by the importance of radio polarization in identifying the FRB origin. We first numerically simulate or calculate the XRB spectrum for each model and fit it to the observed data, then compute the corresponding polarization signal based on the fit. We find that these three models predict different polarization patterns in terms of phase/time and energy variations. The differences can be used to test the models with future X-ray polarization observations. [ABSTRACT FROM AUTHOR]

Catalytic ozonation is a potential technology to eliminate refractory organic contaminants with the low concentration in secondary effluent from industrial park wastewater treatment plants (IPWWTPs). In this study, the catalytic ozonation over the Mn-based catalyst significantly improved the chemical oxygen demand (COD), total organic carbon (TOC), and UV254 removals of secondary effluent from IPWWTPs. The Mn-based catalyst/O3 system achieved 84.8%, 69.8%, and 86.4% removals of COD, TOC, and UV254, which were 3.3, 5.7, and 1.1 times that in ozonation alone, respectively. Moreover, the Mn-based catalytic ozonation process exhibited excellent pH tolerance ranging from pH 4.0 to 9.0. Additionally, the depth analysis based on fluorescence excitation-emission matrix (EEM) confirmed that the catalytic ozonation process preferred to degrade toxic aromatic hydrocarbons. The existence of the Mn-based catalyst/O3 system enhanced 21.4%–38.3% more fluorescent organic matters removal, compared to that in ozonation alone. Mechanistic studies proved that the abundant Lewis acid sites (Mnn+/Mn(n+1)+ and adsorbed oxygen) on the surface of the Mn-based catalyst effectively promoted O3 decomposition into reactive oxygen species (ROS), and ·O2−/HO2· and 1O2 were the main ROS for degrading refractory organic contaminants. The contributions of ROS oxidation (91.2%) was much higher than that of direct O3 oxidation (8.8%). Thus, this work provides an effective advanced treatment process for purifying secondary effluent from IPWWTPs. [ABSTRACT FROM AUTHOR]

In order to explore the influence of microorganisms from different sources on the composting process of grape branch and pig manure, 3 treatments were set including no external microorganisms (CK), inoculated biogas slurry (T1), and inoculated microbial inoculum (T2) . The temperature, moisture content, pH, electrical conductivity (EC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), seed germination index (GI), bacterial and fungal communities were analyzed during the composting process to determine the key microbial in the composting process. The results showed that the temperature of T1 was higher than that of T2 treatment in the early stage of composting with over 45 °C at the 3rd day, and the maximum temperature all reached 60 °C in 3 treatments. The changes of moisture, pH, EC and nutrient content of compost in each treatment were consistent, and the contents of TN, TP and TK were 3.43%~3.59%, 1.46%~1.56% and 1.87%~2.02%, respectively. The moisture content, pH and EC of compost in T2 were higher than those in other treatments after composted. The germination indexes of CK and T1 treatment exceeded 70% on the 30th day, and reached the organic fertilizer standard faster than T2 treatment. The results of microbial community analysis showed that the relative abundance of Proteobacteria and Firmicutes exceeded 75% in the early stage, Firmicutes was the dominant phylum in the middle stage, and the relative abundances of Bacteroides and Deinococcus-Thermus increased in the middle and final stages, and their final proportions exceeded 20%. There were significant correlations between Firmicutes, Bacteroides, Deinococcus-Thermus and indicators of composting. The analysis of contribution degree showed that the total contribution degree of microbial community to composting was 33.90%, and the contribution degree of Gemmatimonadetes was 80.80%. Above results provided a reference for further research and screening of special antioxidant resistant microorganism inoculants. [ABSTRACT FROM AUTHOR]

Flexible temperature sensors have diverse applications and a great potential in the field of temperature monitoring, including healthcare, smart homes and the automotive industry. However, the current flexible temperature sensor preparation generally suffers from process complexity, which limits its development and application. In this paper, a nickel oxide (NiO) flexible temperature sensor based on a low-temperature sintering technology is introduced. The prepared NiO flexible temperature sensor has a high-resolution temperature measurement performance and good stability, including temperature detection over a wide temperature range of (25 to 70 °C) and a high sensitivity performance (of a maximum TCR of −5.194%°C−1 and a thermal constant of 3938 K). The rapid response time of this temperature sensor was measured to be 2 s at 27–50 °C, which ensures the accuracy and reliability of the measurement. The NiO flexible temperature sensor prepared by electrohydrodynamic direct writing has a stable performance and good flexibility in complex environments. The temperature sensor can be used to monitor the temperature status of the equipment and prevent failure or damage caused by overheating. [ABSTRACT FROM AUTHOR]

Soil organic matter is assumed to accumulate with conservation management. Onfarm surveys using paired-farm and chronosequence approaches could validate assumptions, as well as provide a diversity of soils and management conditions to assess organic matter fractions. The objective of this study was to assess how land use and pasture management affected the gradient of organic matter fractions from active to resistant. Particulate and non-particulate (also called mineral-associated) organic C and N fractions were isolated and soil-test biological activity was measured from 304 profiles at 0- to 10-, 10- to 30-, and 30- to 60-cm depths on 31 private farms in Virginia. Root-zone enrichment contents of these soil properties were calculated following subtraction of a baseline from total stocks of each soil profile. Land use was a key factor affecting root-zone enrichment (0- to 30-cm depth) of particulate organic C (Mg C ha−1) (p ≤ 0.05): conventional-till cropland (6.3) = no-till cropland (9.2) < grassland (14.2) < woodland (16.7). Root-zone enrichments of soil C and N fractions increased with pasture age to a plateau achieved by 25 years and were optimized at cattle stocking rate of 1.0 ± 0.2 Mg live weight ha−1. Feeding hay increased root-zone enrichment of soil-test biological activity (49 kg CO2-C 3 day−1 [Mg hay]−1). Although non-particulate organic C and N dominated, accumulation with time and steady-state concentration of particulate fractions were vital steps toward greater soil organic matter under conservation management. Root-zone enrichment calculations from on-farm sampling were helpful in distinguishing true effects of management from pedogenesis on soil organic matter formation. [ABSTRACT FROM AUTHOR]

Cotton textiles improved with metal oxide nanoparticles acquire additional features that may enhance their action against antimicrobial-resistant pathogens due to the unique properties and characteristics of the nanoparticles. The main objective of this work is to evaluate the antimicrobial features of two-sided-coated cotton textiles with ZnO nanoparticles. Nanoparticles were deposited using green chemistry technology with low-temperature oxygen plasma. ZnO particles formed stable structures on textile fibers. The optimal deposition parameters (150 W plasma power, 120 min immersion time) achieved the best effects against Gram-negative and Gram-positive bacteria and microscopic fungi. Two-sided-coated cotton with ZnO nanoparticles showed high antibacterial action on Gram-negative and Gram-positive bacteria. Modification with zinc oxide inhibited the growth of Candida albicans by more than half. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the biochemical and microbiological properties of Cotton–Copper composite materials obtained using magnetron sputtering technology. Copper particles were precisely distributed on the fabric surface, ensuring free airflow without the need to create additional layers. The Cotton–Copper composite materials were subjected to physiochemical and biological investigations. The physiochemical analysis included the elemental analysis of composites (C, N, O, S, Cu) and analyses of their microscopic and surface properties (specific surface area and total pore volume). The biological investigations consisted of microbiological and biochemical–hematological tests, including evaluation of the activated partial thromboplastin time and prothrombin time. Experiments showed significant effectiveness of the antibacterial material against representative strains of fungi and bacterial species. We also demonstrated the ability of the cotton–copper material to interact directly with the plasmid DNA. [ABSTRACT FROM AUTHOR]

Conformal organic field-effect transistors (OFETs) have attracted tremendous attention for nextgeneration skin-like electronics due to their mechanical flexibility, low-cost, large-area fabrication, and tunable electrical performance. However, the reported commercial polymer dielectrics suffer from poor solvent resistance, and the limited available antisolvent dielectrics such as hydroxyl-containing PVA and PVP dielectrics OFETs exhibit poor electrical stability. Herein, a nonpolar polysulfone (PSU) dielectric is firstly integrated into solution-processed OFETs and serves as the dielectric layer. Compared with commonly used dielectrics such as PMMA, PS, PVA, and PVP, PSU possesses enhanced solvent stability, thermal stability, humidity stability, and capacitance stability. The solvent resistant PSU dielectric enables the solution-processed C8-BTBT OFET array to achieve on-state currents over 1 mA and ultrahigh mobility up to 10.84 cm² V-1 s -1 (1 Hz). The PSU dielectric OFETs also exhibit excellent cycle stability, thermal stability, humidity stability, and bias stability. Moreover, the conformal OFETs demonstrate ultrahigh mobility (9.34 cm² V-1 s-1), even when adhering to the limited bending radius down to 1 mm, which is the highest mobility among the reported conformal OFETs. Even after crumpling 50 times, there is no significant decrease in electrical performance. Our results provide a novel dielectric selection for stable solution-processed organic transistors, and show the huge potential of PSU dielectrics in future wearable skin-like electronics. [ABSTRACT FROM AUTHOR]

This study was part of a preliminary safety assessment for a real project of existing bridge piles passing through beaded karst caves threatened by a nearby newly built embankment. To investigate the severity of the effect of the embankment on the performance of these piles, a series of reduced-scale model experiments of piles considering different cave numbers (n = 0, 1, 2, and 3) near surcharge loads were designed with a similarity ratio of 1:35. Two phases of loading, the vertical loading atop the pile and nearby surcharge loading, were imposed successively to explore the vertical bearing characteristic and lateral response characteristic of the piles passing through beaded karst caves. The effects of cave number, vertical load atop the pile, and nearby surcharge load on the responses of pile and soil were clarified and several fitting functions were presented to characterize the variations of responses with different cave numbers and nearby surcharge loads. The results and conclusions can provide a reference for the design and safety assessment of bridge piles in karst terrains. [ABSTRACT FROM AUTHOR]

In recent years, more and more attention has been paid towards the microplastics (MPs) in soil. However, not only microplastics but also heavy metals are present in the soil. The coexistence of microplastics and heavy metals in soil will affect plants growth and plant-fungi symbiotic system. Some studies have shown that the tolerance of plants to heavy metals is enhanced by plants-arbuscular mycorrhizal fungi (AMF) symbiotic system. However, the colonization of AMF in plant roots and the abilities of AMF to filter and chelate heavy metals would be affected by microplastics, thus affecting the accumulation of heavy metals in plants. The plasticizers, stabilizers, flame retardants, and other harmful substances, which can be toxic to plants and AMF, will be released along with the microplastics as they degrade. Furthermore, the sub-micron plastics and nano-plastics directly entered plant root, stem, leaf and fruit. Microplastics adhered to plant seeds and roots to affect plant germination and seedling growth, consequently altering the colonization of AMF on plant roots. Additionally, heavy metals are adsorbed by microplastics due to their characteristics of large surface area, strong hydrophobicity, and slow degradation. However, the influence factors of adsorption included the type of microplastics, heavy metals and environmental conditions. Microplastics will affect the soil physical and chemical properties, such as the soil pH, organic carbon, cation exchange capacity. Moreover, competitive adsorption of microplastics and soil particles for heavy metal ions will change the bioavailability of heavy metals and affect heavy metal accumulation in plants. Although numerous studies have been conducted on the co-contamination of microplastics and heavy metals, there is insufficient information regarding the impacts of co-contamination of microplastics and heavy metal on the plant-AMF symbiotic system. Therefore, this article provides a summary and some suggestions about effects of co-contamination of microplastics and heavy metals on plants and AMF for further studies. [ABSTRACT FROM AUTHOR]

Copyright of Electronic Components & Materials is the property of Electronic Components & Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)