Broadband and perfect terahertz absorber based on multilayer metamaterial using cross-ring patterned structures is proposed and *** structure of the absorber is double absorption layers consisting of a chromium cross ...
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Broadband and perfect terahertz absorber based on multilayer metamaterial using cross-ring patterned structures is proposed and *** structure of the absorber is double absorption layers consisting of a chromium cross ring and eight isosceles right *** unique structure of the double absorbing layers excites the electric dipole multimode resonance,giving rise to high absorption ***,the influence of construal parameters on absorber behavior is also *** numerical results show that the absorption achieves over 90%ranging from 2.45 THz to 6.25 THz and 99%absorption in the range of 3.7—5.3 *** realization of broadband and perfect absorber is described using the impedance matching *** is obviously found that the absorber is insensitive to the high angle of incidence for both transverse electric(TE)and transverse magnetic(TM)*** with the former reports,this absorber has remarkable improved absorption efficiency and smaller *** terahertz absorber may be found applications in the fields of energy capture and thermal detection.
Biomass-derived heteroatom self-doped cathode catalysts has attracted considerable interest for electrochemical advanced oxidation processes(EAOPs)due to its high performance and sustainable ***,we illustrated the mor...
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Biomass-derived heteroatom self-doped cathode catalysts has attracted considerable interest for electrochemical advanced oxidation processes(EAOPs)due to its high performance and sustainable ***,we illustrated the morphological fates of waste leaf-derived graphitic carbon(WLGC)produced from waste ginkgo leaves via pyrolysis temperature regulation and used as bifunctional cathode catalyst for simultaneous H_(2)O_(2) electrochemical generation and organic pollutant degradation,discovering s/N-self-doping shown to facilitate a synergistic effect on reactive oxygen species(ROs)*** the optimum temperature of 800℃,the WLGC exhibited a H_(2)O_(2) selectivity of 94.2%and tetracycline removal of 99.3%within 60 *** functional theory calculations and in-situ Fourier transformed infrared spectroscopy verified that graphitic N was the critical site for H_(2)O_(2) *** pyridinic N and thiophene s were the main active sites responsible for OH generation,N vacancies were the active sites to produce ^(1)O_(2) from O_(2).The performance of the novel cathode for tetracycline degradation remains well under a wide pH range(3–11),maintaining excellent stability in 10 *** is also industrially applicable,achieving satisfactory performance treating in real water *** system facilitates both radical and non-radical degradation,offering valuable advances in the preparation of cost-effective and sustainable electrocatalysts and hold strong potentials in metal-free EAOPs for organic pollutant degradation.
Based on the hindcasts from five subseasonal-to-seasonal(s2s)models participating in the s2s Prediction Project,thisstudy evaluates the performance of the multimodel ensemble(MME)approach in predicting the subseasona...
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Based on the hindcasts from five subseasonal-to-seasonal(s2s)models participating in the s2s Prediction Project,this study evaluates the performance of the multimodel ensemble(MME)approach in predicting the subseasonal precipitation anomalies during summer in China and reveals the contributions of possible driving *** results suggest that while single-model ensembles(sMEs)exhibit constrained predictive skills within a limited forecast lead time of three pentads,the MME illustrates an enhanced predictive skill at a lead time of up to four pentads,and even six pentads,in southern *** on both deterministic and probabilistic verification metrics,the MME consistently outperforms sMEs,with a more evident advantage observed in probabilistic *** superior performance of the MME is primarily attributable to the increase in ensemble size,and the enhanced model diversity is also a contributing *** reliability of probabilistic skill is largely improved due to the increase in ensemble members,while the resolution term does not exhibit consistent ***,the Madden–Julian Oscillation(MJO)is revealed as the primary driving factor for the successful prediction of summer precipitation in China using the *** improvement by the MME is not solely attributable to the enhancement in the inherent predictive capacity of the MJO itself,but derives from its capability in capturing the more realistic relationship between the MJO and subseasonal precipitation anomalies in *** study establishes a scientific foundation for acknowledging the advantageous predictive capability of the MME approach in subseasonal predictions of summer precipitation in China,and sheds light on further improving s2s predictions.
In recent years, machine learning (ML) techniques have been shown to be effective in accelerating the development process of optoelectronic devices. However, as"black box"models, they have limited theoretical interpre...
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In recent years, machine learning (ML) techniques have been shown to be effective in accelerating the development process of optoelectronic devices. However, as"black box"models, they have limited theoretical interpretability. In this work, we leverage symbolic regression (sR) technique for discovering the explicit symbolic relationship between the structure of the optoelectronic Fabry-Perot (FP) laser and its optical field distribution, which greatly improves model transparency compared to ML. We demonstrated that the expressions explored through sR exhibit lower errors on the test set compared to ML models, which suggests that the expressions have better fitting and generalization capabilities.
Near-eutectic Al-si alloys are widely used in automotive manufacturing due to their superior wear resistance and high temperature *** of high si content,the grain refinement of near-eutectic Al-si alloy has been a pro...
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Near-eutectic Al-si alloys are widely used in automotive manufacturing due to their superior wear resistance and high temperature *** of high si content,the grain refinement of near-eutectic Al-si alloy has been a problem for many *** this study,the effect of deep cryogenic treatment(DCT)on the microstructure and mechanical properties of Al-12si-4Cu-2Ni-Mg alloy with addition of Al-Ti-C-B master alloy was fully *** show that the average grain size of the alloy is greatly reduced from 0.92 mm to 0.50 mm,and the eutectic si and Al7Cu4Ni precipitates are spheroidized and refined in Al-12si-4Cu-2Ni-Mg after DCT for 24 h and aging *** these changes of microstructures result in a significant increment of about 22.5%in elongation and a slight enhancement of about 6.8%in tensile ***,the refinement of microstructure also significantly improves the fatigue life of the alloy.
solar-induced water oxidation reaction（WOR） for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages. WOR is also associate...
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solar-induced water oxidation reaction（WOR） for oxygen evolution is a critical step in the transformation of Earth's atmosphere from a reducing to an oxidation one during its primordial stages. WOR is also associated with important reduction reactions, such as oxygen reduction reaction（ORR）, which leads to the production of hydrogen peroxide（H2O2）. These transitions are instrumental in the emergence and evolution of life. In this study, transition metals were loaded onto nitrogen-doped carbon（NDC） prepared under the primitive Earth's atmospheric conditions. These metal-loaded NDC samples were found to catalyze both WOR and ORR under light illumination. The chemical pathways initiated by the pristine and metal-loaded NDC were investigated. This study provides valuable insights into potential mechanisms relevant to the early evolution of our planet.
Phosphorus(P)is the main limiting factor in *** P can be released decades after its *** restoration requires the reduction of internal sediment P *** we tried to provide a comprehensive summary of the state-of-the-art...
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Phosphorus(P)is the main limiting factor in *** P can be released decades after its *** restoration requires the reduction of internal sediment P *** we tried to provide a comprehensive summary of the state-of-the-art sediment P control technologies,our analyses in this review are focused on the mechanisms,control effects,and application conditions of different in-situ technologies including physical control,chemical control,ecological remediation,and combined control *** design principles,feasibility,operation parameters,and pros&cons of these technologies are analyzed and *** efforts are needed to improve in-situ sediment P control technologies so as to enhance the interaction between materials and plant communities and promote the adsorption and fixation of active P in *** control materials for internal sediment P loading need to be further studied in terms of their functional properties,pre-evaluation of the P control effect,and engineering applications.
The development of effective adsorbents with high amine efficiency and CO_(2)adsorption almost unaffected by humidity is extremely *** thisstudy,we introduce an innovative solid amine adsorbent,TETA/DEA@Fs,composed o...
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The development of effective adsorbents with high amine efficiency and CO_(2)adsorption almost unaffected by humidity is extremely *** this study,we introduce an innovative solid amine adsorbent,TETA/DEA@Fs,composed of triethylenetetramine(TETA)and diethanolamine(DEA)functionalized fumed silica(Fs),which exhibits exceptional capability in selectively capturing trace CO_(2)from N_(2).TETA/DEA@Fs shows an exceptionally high capacity of CO_(2)adsorption of 1.13 mmol/g at the temperature of 298 K and the pressure of 0.0004 bar(1 bar=100 kPa),and achieves an unprecedented CO_(2)/N_(2)IAsT selectivity of 1.70×10^(12).TETA/DEA@Fs exhibits high amine efficiency,with breakthrough experiments demonstrating that CO_(2)adsorption remains nearly unaffected by ***,TETA/DEA@Fs demonstrates rapid CO_(2)adsorption kinetics and outstanding cyclic stability.
Precise polyp segmentation is vital for the early diagnosis and prevention of colorectal cancer(CRC)in clinical ***,due to scale variation and blurry polyp boundaries,it isstill a challenging task to achieve satisfac...
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Precise polyp segmentation is vital for the early diagnosis and prevention of colorectal cancer(CRC)in clinical ***,due to scale variation and blurry polyp boundaries,it is still a challenging task to achieve satisfactory segmentation performance with different scales and *** this study,we present a novel edge-aware feature aggregation network(EFA-Net)for polyp segmentation,which can fully make use of cross-level and multi-scale features to enhance the performance of polyp ***,we first present an edge-aware guidance module(EGM)to combine the low-level features with the high-level features to learn an edge-enhanced feature,which is incorporated into each decoder unit using a layer-by-layer ***,a scale-aware convolution module(sCM)is proposed to learn scale-aware features by using dilated convolutions with different ratios,in order to effectively deal with scale ***,a cross-level fusion module(CFM)is proposed to effectively integrate the cross-level features,which can exploit the local and global contextual ***,the outputs of CFMs are adaptively weighted by using the learned edge-aware feature,which are then used to produce multiple side-out segmentation *** results on five widely adopted colonoscopy datasets show that our EFA-Net outperforms state-of-the-art polyp segmentation methods in terms of generalization and *** implementation code and segmentation maps will be publicly at https://***/taozh2017/EFANet.
As an extension of linear regression in functional data analysis, functional linear regression has been studied by many researchers and applied in various fields. However, in many cases, data is collected sequentially...
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As an extension of linear regression in functional data analysis, functional linear regression has been studied by many researchers and applied in various fields. However, in many cases, data is collected sequentially over time, for example the financial series, so it is necessary to consider the autocorrelated structure of errors in functional regression background. To this end, this paper considers a multiple functional linear model with autoregressive errors. Based on the functional principal component analysis, we apply the least square procedure to estimate the functional coefficients and autoregression coefficients. Under some regular conditions, we establish the asymptotic properties of the proposed estimators. A simulation study is conducted to investigate the finite sample performance of our estimators. A real example on China's weather data is applied to illustrate the validity of our model.
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