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Gaseous iodine compounds especially radioactive iodine compounds such as CH 3 I from nuclear spent fuel, once discharged, being destructive to the environment and harmful to human health are usually captured by solid adsorption. The faujasite (FAU) composed of Si, Al, and O elements is a kind of porous material with a high specific surface area usually used as an adsorbent and catalyst carrier. Excessive micropores in the skeleton of FAU hinder the diffusion of gas molecules to reduce the adsorption efficiency. In the NH 4 F solution, the skeleton of FAU was selectively corroded by F - ions and rearranged to form the construction with different the distribution of pore size. Ag-oxide nanoclusters were deposited inside the mesoporous and microporous pores of corroded FAU by the photoreduction method. To regulate the distribution of pore size, FAU deposited Ag-oxide nanocluster with more mesoporous and microporous pores providing more sufficient space for the diffusion of gaseous CH 3 I presented more excellent adsorption performance. [ABSTRACT FROM AUTHOR]

T1-weighted (T1w) MRI has low frequency intensity artifacts due to magnetic field inhomogeneities. Removal of these biases in T1w MRI images is a critical preprocessing step to ensure spatially consistent image interpretation. N4ITK bias field correction, the current state-of-the-art, is implemented in such a way that makes it difficult to port between different pipelines and workflows, thus making it hard to reimplement and reproduce results across local, cloud, and edge platforms. Moreover, N4ITK is opaque to optimization before and after its application, meaning that methodological development must work around the inhomogeneity correction step. Given the importance of bias fields correction in structural preprocessing and flexible implementation, we pursue a deep learning approximation / reinterpretation of the N4ITK bias fields correction to create a method which is portable, flexible, and fully differentiable. In this paper, we trained a deep learning network "DeepN4" on eight independent cohorts from 72 different scanners and age ranges with N4ITK-corrected T1w MRI and bias field for supervision in log space. We found that we can closely approximate N4ITK bias fields correction with naïve networks. We evaluate the peak signal to noise ratio (PSNR) in test dataset against the N4ITK corrected images. The median PSNR of corrected images between N4ITK and DeepN4 was 47.96 dB. In addition, we assess the DeepN4 model on eight additional external datasets and show the generalizability of the approach. This study establishes that incompatible N4ITK preprocessing steps can be closely approximated by naïve deep neural networks, facilitating more flexibility. All code and models are released at https://github.com/MASILab/DeepN4. [ABSTRACT FROM AUTHOR]

As the most common filler in stormwater treatment, zeolite (NZ-Y) has good cation exchange capability and stabilization potential for the removal of heavy metal from aqueous solutions. In this study, sodium dodecyl sulfate (SDS) and NZ-Y were selected to preparing new adsorbent (SDS-NZ) by using a simple hydrothermal method. The sorption–desorption performance and mechanism of Cu(II) onto SDS-NZ were investigated. The results showed that the sorption of Cu(II) on SDS-NZ was in accordance with the pseudo-second-order kinetic model with an equilibrium time of 4 h. The sorption behavior fitted Langmuir isotherm with a saturation sorption capability of 9.03 mg/g, which was three times higher than that of NZ-Y. The modification of SDS increases the average pore size of NZ-Y by 3.96 nm, which results in a richer internal pore structure and more useful sorption sites for Cu(II) sorption. There was a positive correlation between solution pH values and sorption capability of Cu(II) in the range of 3.0–6.0. With the ionic strength increased, the sorption capability of Cu(II) onto SDS-NZ first decreased and then increased, which may be attributed to competitive sorption and compression of the electronic layer. The desorption of Cu(II) on SDS-NZ was favored by the increase in SDS concentration and ionic strength and decrease in solution pH values. The application of SDS-NZ in runoff improved the leaching risk of Cu(II). After several cycles, the ability of reused SDS-NZ to efficiently adsorb most heavy metals was verified with removal rates above 99%. [ABSTRACT FROM AUTHOR]

Lead graphite/copper-matrix composites are commonly used in pantograph sliders for rail transit. However, the use of lead is harmful to the environment and has been restricted in most countries. In this work, the Bi-containing graphite/copper-matrix composite with different bismuth content has been manufactured via hot powder forging. The bonding between copper and graphite has been improved through improvements in the preparation process. The tensile strength increased first and then decreased with the additional content of bismuth, and the maximum tensile strength was 137.62 MPa. The friction coefficient increased first and then decreased as the current density raising, while the wear rate just kept increasing. Meanwhile, the friction mechanism changes from an adhesive wear mechanism to an electrical wear mechanism. The energy dispersive spectroscopy mapping revealed the good film-forming properties of bismuth. The results show that the mechanical and current-carrying wear properties of the Bi-containing graphite/copper-matrix composite are comparable with those of lead-containing graphite/copper-matrix composites, indicating a potential pantograph slider alternative. [ABSTRACT FROM AUTHOR]

Negative interpersonal attitudes can affect people's well-being, interpersonal relationships, and cooperation. Overcoming negative interpersonal attitudes is a key subject in loving-kindness and compassion meditations (LCMs). However, the results and study design of previous research on negative interpersonal attitudes have been inconsistent. Therefore, it is necessary to summarize the effects of LCMs and explore moderators through meta-analysis. A literature search was conducted in the Cochrane Central Register of Controlled Trials, ISI Core Collection, Medline, ProQuest Dissertations & Theses, and PsycINFO databases up to April 2, 2021. Of the 281 identified empirical studies on LCMs, 25 measured negative interpersonal attitudes, and 21 were included in the meta-analysis. The results showed that the effects of LCMs on negative interpersonal attitudes in daily life were significant both for randomized controlled trials (g = -.203) and uncontrolled trials (g = -.539). The instant effects after meditation were also significant in randomized controlled experiments (g = -.187). Leave-one-out sensitivity analysis and nonsignificant subgroup analysis showed that the results were robust except for randomized controlled experiments. Although no significant moderators were identified, moderator analysis suggested that reducing bias and sending wishes to difficult targets were especially effective, and LCM subtypes might impact the results. Individual studies found that the contribution of meditation practice during interventions was weak. In sum, LCMs have the potential to reduce negative interpersonal attitudes, especially in multiweek interventions. Future studies should further explore the underlying mechanisms and consider the implications of study design features, such as the induction of negative interpersonal attitudes and the targets of LCMs. [ABSTRACT FROM AUTHOR]

Objectives: It is debatable whether loving-kindness and compassion meditation (LKCM) effectively reduces anxiety, and previous studies have reported inconsistent findings. This study provides a systematic review and meta-analysis of the effects of LKCM on anxiety. Method: Studies that took LKCM as the main body and measured anxiety as an outcome were included. There were no exclusion criteria for sample characteristics or control groups. Results: Among 327 empirical studies published up to March 2022 on LKCM, 59 measured anxiety as an outcome. Meta-analyses showed that LKCM interventions are effective in reducing anxiety (d = -0.28, k = 19, n = 1284 for randomized controlled trials; d = -0.48, k = 26, n = 1177 for nonrandomized trials; d = -0.58, k = 6, n = 503 for laboratory experiments). The heterogeneity was high between studies. Subgroup analyses for randomized controlled trials found that studies combining loving-kindness meditation and mindfulness meditation outperformed studies adopting loving-kindness meditation alone. Moreover, studies with waitlist controls had greater effect sizes than studies with active controls. The type of anxiety, participant characteristics, protocol, or length of intervention had no statistically significant moderating effects. Individual studies supported mindfulness and self-compassion as important mechanisms, but the amount of meditation practice made a limited contribution. Conclusions: LKCM interventions can be effective in reducing anxiety. The incremental value of combining mindfulness meditation with loving-kindness meditation is encouraging. More research is needed, especially on specific populations suffering from anxiety disorders. Preregistration: PROSPERO CRD42021245515 [ABSTRACT FROM AUTHOR]

The copper/carbon-matrix (Cu/C) composites have a wide application prospect in high-speed railway pantograph sliders due to both the self-lubrication of carbon and the good conductivity of copper. However, the poor wettability between copper and carbon affects the interface bonding strength. In this work, the carbonizable element chromium powder was added into the composite system, and the Cr-Cu/C composites were fabricated by hot pressing and sintering process. The interface phase of Cr3C2 between copper and the carbon matrix was determined, which results from the interface reaction between chromium and carbon, leading to the improvement of the bonding of copper and carbon. Meanwhile, the mechanical and current-carrying wear performances can be enhanced significantly with the addition of chromium. The results demonstrate that the Cr-Cu/C composite with 0.48wt% Cr has the best comprehensive performance, which includes the compressive strength of 62.82 MPa, the flexural strength of 26.72 MPa, the impact strength of 0.17 J cm−2 and the electrical resistivity of 31.28 μΩ m, respectively, and this composite has the lowest wear rate and friction coefficient. It is also found that with the alteration of current density change from 5 A cm−2 to 10 A cm−2, the wear mechanism changes from abrasive wear to adhesive wear. With the introduction of chromium, a certain thickness of Cr3C2 layer is formed at the interface between copper and carbon, which can improve the wettability of copper and carbon obviously, enhancing bonding effect and reducing pores. Therefore, the novel copper/carbon-matrix composites have excellent mechanical and current-carrying wear performances at current densities of 5 A cm−2 and 10 A cm−2. [ABSTRACT FROM AUTHOR]

Since 2013, a pilot market of carbon emission trading scheme (ETS) has operated in China, with results showing a reduction in the carbon intensity of the economy. How does ETS affect enterprises' environmental protection behaviors? We conducted a quasinatural experiment by using A-share-listed companies from 2010 to 2019 as research samples and matching them using the propensity score matching method. The difference in differences model was then used to empirically assess the effect and influencing mechanism of the ETS on corporate environmental investment. Finally, the robustness and heterogeneity of the empirical results were checked. ETS seems to have significantly increased the levels of capitalized and expense-based environmental protection investment. Among them, low-carbon technological innovation plays an intermediary role in the impact of ETS on capitalized environmental protection investment. State-owned enterprises preferred capitalized environmental protection investment, whereas private enterprises preferred expense-based environmental protection investment. Moreover, having a political connection could compromise the role of ETS in promoting environmental protection investment. Our study provides some suggestions, such as accelerating the rollout of low-carbon technologies, increasing financial support for private enterprises, establishing an official reputation mechanism, and strengthening the transparency of carbon emission information disclosure. [ABSTRACT FROM AUTHOR]

To support the safe operation of the novel three-element mixed insulation oil (TEMO) transformer, gas generation behaviors of the TEMO oil–paper insulation system under overheating faults and discharge faults were investigated. Results show that that the content of H2 and C2H6 generated by TEMO–paper insulation system is much higher than that in conventional mineral oil (MO)–paper insulation system under different overheating temperatures. Under partial discharge fault, the content of H2 dissolved in oil changes distinctly, while the content of C2H2 also increases with the discharge time. Under surface flashover breakdown, AC breakdown and lightning impulse breakdown fault, the content of H2 and C2H2 changes greatly compared to other gases, while the concentration of total hydrocarbon gases in TEMO–paper insulation system is smaller than that in MO–paper insulating system after the same breakdown times. The diagnosis model of overheating and discharge faults for the TEMO–paper insulation system was proposed based on the oil dissolved gas analysis, while H2, C2H2 and C2H4 were chosen as the characteristic gases and the boundary settings were determined. The verified result for the low-temperature overheating, lightning impulse and surface flashover fault for the TEMO–paper insulation system presents that the new diagnosis model is effective. [ABSTRACT FROM AUTHOR]