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An mmWave Dual-Band Integrated Substrate Gap Waveguide Single Cavity Filter with Frequency Selectivity
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作者 Qiuhua Lin Dongya Shen +1 位作者 Lihui Wang Zhiyong Luo 《China Communications》 SCIE CSCD 2024年第1期188-199,共12页
A novel dual-band ISGW cavity filter with enhanced frequency selectivity is proposed in this paper by utilizing a multi-mode coupling topology.Its cavity is designed to control the number of modes,and then the ports a... A novel dual-band ISGW cavity filter with enhanced frequency selectivity is proposed in this paper by utilizing a multi-mode coupling topology.Its cavity is designed to control the number of modes,and then the ports are determined by analyzing the coupling relationship between these selected modes.By synthesizing the coupling matrix of the filter,a nonresonating node(NRN)structure is introduced to flexibly tune the frequency of modes,which gets a dualband and quad-band filtering response from a tri-band filter no the NRN.Furthermore,a frequency selective surface(FSS)has been newly designed as the upper surface of the cavity,which significantly improves the bad out-of-band suppression and frequency selectivity that often exists in most traditional cavity filter designs and measurements.The results show that its two center frequencies are f01=27.50 GHz and f02=32.92GHz,respectively.Compared with the dual-band filter that there is no the FSS metasurface,the out-of-band suppression level is improved from measured 5 dB to18 dB,and its finite transmission zero(FTZ)numbers is increased from measured 1 to 4 between the two designed bands.Compared with the tri-band and quadband filter,its passband bandwidth is expanded from measured 1.17%,1.14%,and 1.13% or 1.31%,1.50%,0.56%,and 0.57% to 1.71% and 1.87%.In addition,the filter has compact,small,and lightweight characteristics. 展开更多
关键词 coupling topology frequency selectivity non-resonating node(NRN) out-of-band suppression single ISGW cavity filter
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Effects of biomass co-pyrolysis and herbaceous plant colonization on the transformation of tailings into soil like substrate 被引量:1
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作者 Bin Zhu Meiyan Si +4 位作者 Xin Xie Ximin Yan Jianhong Huang Senlin Tian Ping Ning 《Journal of Environmental Sciences》 2025年第1期230-243,共14页
Enhancing soil organic matter characteristics,ameliorating physical structure,mitigating heavy metal toxicity,and hastening mineral weathering processes are crucial approaches to accomplish the transition of tailings ... Enhancing soil organic matter characteristics,ameliorating physical structure,mitigating heavy metal toxicity,and hastening mineral weathering processes are crucial approaches to accomplish the transition of tailings substrate to a soil-like substrate.The incorporation of biomass co-pyrolysis and plant colonization has been established to be a significant factor in soil substrate formation and soil pollutant remediation.Despite this,there is presently an absence of research efforts aimed at synergistically utilizing these two technologies to expedite the process of mining tailings soil substrate formation.The current study aimed to investigate the underlying mechanism of geochemical changes and rapid mineral weathering during the process of transforming tailings substrate into a soil-like substrate,under the combined effects of biomass co-smoldering pyrolysis and plant colonization.The findings of this study suggest that the incorporation of smoldering pyrolysis and plant colonization induces a high-temperature effect and biological effects,which enhance the physical and chemical properties of tailings,while simultaneously accelerating the rate of mineral weathering.Notable improvements include the amelioration of extreme pH levels,nutrient enrichment,the formation of aggregates,and an increase in enzyme activity,all of which collectively demonstrate the successful attainment of tailings substrate reconstruction.Evidence of the acceleratedweathering was verified by phase and surfacemorphology analysis using X-ray diffraction and scanning electron microscopy.Discovered corrosion and fragmentation on the surface ofminerals.The weathering resulted in corrosion and fragmentation of the surface of the treated mineral.This study confirms that co-smoldering pyrolysis of biomass,combined with plant colonization,can effectively promote the transformation of tailings into soil-like substrates.This method has can effectively address the key challenges that have previously hindered sustainable development of the mining industry and provides a novel approach for ecological restoration of tailings deposits. 展开更多
关键词 SMOLDERING Biomass co-pyrolysis Phytoremediation Soil-like substrate Tailing restoration
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Optimizing the Particle Size of Shale and Laterite Used as Constructed Wetland Substrates for Wastewater Treatment
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作者 Nadège Fatim Traoré Jean-Marie Pétémanagnan Ouattara +2 位作者 Franck Michaël Zahui Amichalé Jean Cyrille Beda Aman Messou 《Journal of Water Resource and Protection》 2025年第1期14-34,共21页
Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth... Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth operation of the process, as hydrodynamic constraints require a coarse particle size, whereas wastewater treatment recommends a fine particle size. This study investigates the suitability of laterite and shale as substrates of different sizes (1 - 3, 3 - 5 and 5 - 8 mm) in CWs for domestic wastewater treatment. The study was carried out in an experimental pilot plant consisting of 12 parallelepiped beds (C × C = 0.4 × 0.4 m2;H = 0.6 m) filled from bottom to top with 0.1 m of gravel and 0.4 m of shale or laterite of different grain sizes with two replications. During the six months of operation, plant biomass and stem diameter of Pennisetum purpureum used as vegetation in the CWs were determined. Raw and treated water were also sampled and analyzed for pollutants, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total Kjedahl nitrogen (TKN), total phosphorus (TP), and total suspended solids (TSS), using International Organization for Standardization (ISO) analytical methods. P. purpureum developed much better in the CW beds lined with shale;plant biomass ranged from 13.8 to 14.7 kg/m2 and from 11.2 to 12.5 kg/m2 in the beds lined with shale and laterite, respectively, as did stump diameter, which ranged from 15.5 to 16.1 cm and from 11.10 to 12.7 cm, respectively. However, the highest values for biomass and stump diameter for each material were obtained in the beds lined with 1 - 3 mm geomaterials. Pollutant removal efficiencies were highest in the CWs lined with laterite and shale of 1 - 3 mm grain size (76.9% - 83% COD, 78% - 84.7% BOD5, 55.5% - 72.2% TKN, 58.4% - 72.4% TP, 78.1% - 80.2% TSS), with the highest values recorded in the shale-lined beds. However, the 3 - 5 mm grain size of both materials provided quality filtrates (140 - 174 mg/L COD, 78.5 - 94.8 mg/L BOD5, 4.6 - 5.7 mg/L TP) in line with local wastewater discharge levels. This size of geomaterials appears to be suitable for optimization purposes, although further work with these materials, such as increasing the depth of the wetland, is required to improve the level of NTK and TSS discharge. 展开更多
关键词 Constructed Wetlands Domestic Wastewater LATERITE Pennisetum purpureum SHALE substrate Grain Size
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Enhanced selectivity of catalytic hydrogenation of halogenated nitroaromatics by interfacial effects
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作者 HUANG Rui LIU Shengjie +1 位作者 WU Qingyuan ZHENG Nanfeng 《无机化学学报》 北大核心 2025年第1期201-212,共12页
The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts c... The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts contained Pd species in mixed valence states,with high valence Pd at the metal‑support interface and zero valence Pd at the metal surface.While the strong coordination of triphenylphosphine(PPh3)to Pd0 on the Pd surface prevents the adsorption of halogenated nitroaromatics and thus dehalogenation,the coordination of sodium metavanadate(NaVO3)to high‑valence Pd sites at the interface helps to activate H2 in a heterolytic pathway for the selective hydrogenation of nitro‑groups.The excellent catalytic performance of the interfacial active sites enables the selective hydrogenation of a wide range of halogenated nitroaromatics. 展开更多
关键词 halogenated nitroaromatic heterogeneous catalysis HYDROGENATION selectivity control interfacial effect
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Selective Area Growth of High-Quality In-Plane GaAs Nanowires and Nanowire Networks by Molecular Beam Epitaxy on Ge Substrates
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作者 Fengyue He Xiyu Hou +3 位作者 Xiuming Dou Yukun Yin Dong Pan Jianhua Zhao 《Chinese Physics Letters》 2025年第6期269-284,共16页
Anti-phase domain defects easily form in the in-plane GaAs nanowires(NWs)grown on CMOS-compatiblegroup IV substrates,which makes it difficult to obtain GaAs NWs with a designed length and also leads to asignificant li... Anti-phase domain defects easily form in the in-plane GaAs nanowires(NWs)grown on CMOS-compatiblegroup IV substrates,which makes it difficult to obtain GaAs NWs with a designed length and also leads to asignificant limitation in the growth of high-quality in-plane GaAs NW networks on such substrates.Here,wereport on the selective area growth of anti-phase domain-free in-plane GaAs NWs and NW networks on Ge(111)substrates.Detailed structural studies confirm that the GaAs NW grown using a large pattern period and GaAsNW networks grown by adding the Sb are both high-quality pure zinc-blende single crystals free of stackingfaults,twin defects,and anti-phase domain defects.Room-temperature photoluminescence measurements show asubstantial improvement in crystal quality and good consistency and uniformity of the GaAs NW networks.Ourwork provides useful insights into the controlled growth of high-quality anti-phase domain-defects-free in-planeIII-V NWs and NW networks. 展开更多
关键词 nanowire networks Ge substrates structural studies high quality plane GaAs nanowires molecular beam epitaxy gaas nws selective area growth gaas nanowires nws grown
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Nanosizing enhancement of hydrogen storage performance and mechanism in Mg-based materials:Nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanisms
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作者 Duode Zhao Xiaojiang Hou +8 位作者 Yu Ge Dongfeng Sun Danting Li Chenlu Wang Xinlei Xie Peixuan Zhu Xiaohui Ye Guoquan Suo Yanling Yang 《Journal of Energy Chemistry》 2025年第10期609-636,共28页
The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics... The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics,thermodynamic stability,inadequate cycling stability,and difficulties in activation impede the commercial utilization of Mg-based composites.Research indicates that reducing material dimensions to the nanoscale represents an efficacious strategy to address these issues.In this work,we systematically analyze the impact of nanosizing on Mg-based composites from three perspectives:nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanism.This analysis aims to provide guidance for the optimization and development of nanosizing strategies.For the regulation of nanosizing of Mg-based composites,the nanosizing of multi-element micro-alloyed Mg-rich systems,the integrated synthesis of multi-element multi-component nano-catalysts,and the coexistence of multiple nano-catalytic mechanisms are proposed in the light of the current state of the art research,artificial intelligence technology,and advanced characterization technology to achieve efficient,multidimensional,and simultaneous regulation of the hydrogen storage performance of Mg-based composites.This paper also envisions future directions and potential applications,emphasizing the importance of interdisciplinary approaches that integrate material science,chemistry,and computational modeling to overcome existing limitations and unlock the full potential of Mg-based hydrogen storage technologies. 展开更多
关键词 Nanosizing Mg-based materials substrate modulation Catalyst Catalytic mechanism
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Fading on the beach:pigmentation plasticity adjusts coloration to substrate type in coastal Western spadefoot toads
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作者 Léa Lorrain-Soligon Frédéric Robin +3 位作者 Vincent Lelong Sébastien Palier Marko Jankovic and Françis Brischoux 《Current Zoology》 2025年第5期593-602,共10页
Animal species exhibit a wide range of coloration and patterns,which are under strong selection and often linked to individual quality,influencing mate choice,recognition,signaling,and interspecific interactions such ... Animal species exhibit a wide range of coloration and patterns,which are under strong selection and often linked to individual quality,influencing mate choice,recognition,signaling,and interspecific interactions such as predator avoidance.In amphibians,coloration can vary based on individual traits as well as environmental conditions,including the coloration of their environment.In this study,we described the dorsal coloration(body coloration reticulated by dark patches)in 676 Western spadefoot toads(Pelobates cultripes)from the French Atlantic coast,comparing color variations across different substrates.In addition,we assessed color change in 18 toads transferred between bright and dark substrates.We demonstrated that the dorsal coloration varies based on capture locations(beach vs.inland)and associated substrate types(bright vs.dark),suggesting background color matching.We showed more pronounced effects in females,which might reflect varying predation risks.Experimentally,we showed that individuals can rapidly adjust their coloration to match the substrate within 24 h.Rapid color changes in response to substrate type indicate significant pigmentation plasticity.Bright individuals from sandy substrates showed less dorsal background(body)color change than dark inland individuals,while patch coloration responded differently depending on the substrate of origin.These findings highlight the complex interactions between substrate type,sex,and pigmentation plasticity.These interactions have potential costs and benefits,which might be linked to melanin production,which warrant further investigation. 展开更多
关键词 AMPHIBIANS background color matching INLAND PATCHES sex-dependent substrate
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Atrial fibrillation substrate mapping with emphasis on voltage-based guidance
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作者 Edward J Ciaccio Henry H Hsia +4 位作者 Hirad Yarmohammadi Elaine Y Wan MD Nicholas S Peters Deepak Saluja Angelo B Biviano 《World Journal of Cardiology》 2025年第11期1-18,共18页
Voltage substrate mapping is a promising tool for the treatment of atrial fibrillation(AF).It is helpful to detect atrial fibrosis,which includes areas with low bipolar voltage,heterogeneous conduction properties,and ... Voltage substrate mapping is a promising tool for the treatment of atrial fibrillation(AF).It is helpful to detect atrial fibrosis,which includes areas with low bipolar voltage,heterogeneous conduction properties,and shortened effective refractory period.The voltage amplitude is typically defined as the maximal peakto-peak level within a specified time window of interest.Contemporary electroanatomic mapping platforms now enable many thousands of data points to be mapped,so that a geometric model of the atrial endocardium is constructable over a short period of time.This mapping procedure is often done with bipolar electrodes to cancel the far-field signal.The recording site coordinates are projected onto an atrial shell,with interpolation of the voltage data across the shell surface.The amplitude of the recorded bipolar electrogram depicted on the threedimensional shell provides detailed information for substrate mapping.Wherever there are areas of low peak-to-peak voltage,it is thought to mark the presence of abnormal tissue properties and conduction.However,uncontrolled variables and environmental factors affecting voltage level include the oncoming electrical activation wavefront direction,the catheter incidence angle,the force applied to the catheter,and the region-variable shape and structure of atrial tissue.Techniques and settings to acquire atrial voltage data for AF analysis have not been standardized.Methods to characterize atrial electrograms are also presently limited.These factors affect quality and reproducibility of the mapping results.Herein,voltage substrate mapping and its variables pertaining to AF and radiofrequency ablation are described and discussed,with suggestions for future work efforts. 展开更多
关键词 Ablation Atrial fibrillation Sinus rhythm substrate mapping VOLTAGE
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Fabrication of Porous SiC Coatings on Quartz Substrates by Laser Chemical Vapor Deposition
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作者 YANG Meijun CHEN Rui +4 位作者 XU Qingfang GUO Bingjian LIU Kai TU Rong ZHANG Song 《Journal of Wuhan University of Technology(Materials Science)》 2025年第2期330-337,共8页
Laser etching and laser chemical vapor deposition(LCVD)techniques were proposed for the rapid preparation of high-purity,strongly bonded SiC porous micro-nano-coatings on quartz substrates.The laser serves as an exter... Laser etching and laser chemical vapor deposition(LCVD)techniques were proposed for the rapid preparation of high-purity,strongly bonded SiC porous micro-nano-coatings on quartz substrates.The laser serves as an external driving force for the vertical growth of SiC whiskers,facilitating the formation of a porous nanostructure that resembles coral models found in the macroscopic biological world.The porous nanostructures are beneficial for reducing thermal expansion mismatch and relieving residual stress.It is capable of eliminating the cracks on the surface of SiC coatings as well as enhancing the bonding of SiC coatings with quartz substrates to avoid coating detachment. 展开更多
关键词 laser etching laser CVD quartz substrate SiC coating
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Inhibition of jarosite heterogeneous crystallization on anglesite via in-situ formation of competitive substrate
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作者 Jiahui Wu Xu Yan +6 位作者 Feiping Zhao Yong Ke Haiying Wang Wenchao Zhang Qingwei Wang Meiqing Shi Liyuan Chai 《Journal of Environmental Sciences》 2025年第3期394-405,共12页
Heterogeneous crystallization is a common occurrence during the formation of solidwastes.It leads to the encapsulation of valuable/hazardous metals within the primary phase,presenting significant challenges for waste ... Heterogeneous crystallization is a common occurrence during the formation of solidwastes.It leads to the encapsulation of valuable/hazardous metals within the primary phase,presenting significant challenges for waste treatment andmetal recovery.Herein,we proposed a novel method involving the in-situ formation of a competitive substrate during the precipitation of jarosite waste,which is an essential process for removing iron in zinc hydrometallurgy.We observed that the in-situ-formed competitive substrate effectively inhibits the heterogeneous crystallization of jarosite on the surface of anglesite,a lead-rich phase present in the jarositewaste.As a result,the iron content on the anglesite surface decreases from34.8%to 1.65%.The competitive substrate was identified as schwertmannite,characterized by its loose structure and large surface area.Furthermore,we have elucidated a novel mechanism underlying this inhibition of heterogeneous crystallization,which involves the local supersaturation of jarosite caused by the release of ferric and sulfate ions from the competitive substrate.The local supersaturation promotes the preferential heterogeneous crystallization of jarosite on the competitive substrate.Interestingly,during the formation of jarosite,the competitive substrate gradually vanished through a dissolution-recrystallization process following the Ostwald rule,where a metastable phase slowly transitions to a stable phase.This effectively precluded the introduction of impurities and reduced waste volume.The goal of this study is to provide fresh insights into the mechanism of heterogeneous crystallization control,and to offer practical crystallization strategies conducive to metal separation and recovery from solid waste in industries. 展开更多
关键词 Heterogeneous crystallization Jarosite waste Competitive substrate Zinc hydrometallurgy
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Utilization of Spent Mushroom Substrate and Local Organic Wastes as Sustainable Growth Media for Enhanced Cocoa Seedling Development
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作者 Karupakorn Laeid-on Arunrussamee Sangsila +1 位作者 Worrawat Promden Tepporn Lomarak 《Journal of Environmental & Earth Sciences》 2025年第1期540-549,共10页
This study examines the effects of germination substrates incorporating spent mushroom substrate(SMS)and locally sourced organic materials on the growth and vigor of cocoa seedlings.Seven treatments were evaluated usi... This study examines the effects of germination substrates incorporating spent mushroom substrate(SMS)and locally sourced organic materials on the growth and vigor of cocoa seedlings.Seven treatments were evaluated using a Completely Randomized Design(CRD),comprising combinations of coconut coir,rice husk,sugarcane bagasse,and biochar.Key findings reveal that treatments combining SMS,sugarcane bagasse,and either coconut coir or biochar(T6 and T7)achieved significantly higher survival rates and Dickson Quality Index(DQI)scores compared to conventional soil(T1).These treatments provided favorable chemical properties,including optimal pH,electrical conductivity,and nutrient content(N,P,K),which are critical for cocoa seedling development.The results suggest that using SMS with agricultural waste as an alternative germination medium can reduce cultivation costs,enhance seedling growth,and contribute to sustainable agricultural practices by repurposing organic waste.This approach not only offers cost-effective benefits for farmers but also mitigates environmental impacts associated with waste disposal. 展开更多
关键词 Spent Mushroom substrate Organic Materials Seeding Cocoa
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Spherical Indentation on a Piezoelectric Semiconductor Film/Elastic Substrate System
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作者 Shijing Gao Guoquan Nie +1 位作者 Jinxi Liu Weiqiu Chen 《Acta Mechanica Solida Sinica》 2025年第5期872-883,共12页
We study the axisymmetric frictionless indentation problem of a piezoelectric semiconductor(PSC)thin film perfectly bonded to a semi-infinite isotropic elastic substrate by a rigid and insulating spherical indenter.Th... We study the axisymmetric frictionless indentation problem of a piezoelectric semiconductor(PSC)thin film perfectly bonded to a semi-infinite isotropic elastic substrate by a rigid and insulating spherical indenter.The Hankel integral transformation is first employed to derive the general solutions for the governing differential equations of the PSC film and elastic substrate.Then,using the boundary and interface conditions,the complicated indentation problem is reduced to numerically solve a Fredholm integral equation of the second kind.Numerical results are given to demonstrate the effects of semiconducting property,film thickness as well as Young’s modulus and Poisson’s ratio of the substrate on the indentation responses.The obtained findings will contribute to the establishment of indentation experiments for PSC film/substrate systems. 展开更多
关键词 INDENTATION Piezoelectric semiconductor Singular integral equation substrate effect Thin film
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Influence of Bromo-Aromatic Substrates on Direct Arylation of EDOTs toward Higher Molecular Conjugate Polymer
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作者 Xi-Lin Pei Quan Yang +3 位作者 Yan-Lu Sun Wei Wu Jian-Yong Yu Yong He 《Chinese Journal of Polymer Science》 2025年第5期718-729,共12页
The influence of the electronic and steric properties of bromoaromatic substrates on direct arylation polymerization for synthesizing high-molecular-weight conjugated polymers was investigated through a combination of... The influence of the electronic and steric properties of bromoaromatic substrates on direct arylation polymerization for synthesizing high-molecular-weight conjugated polymers was investigated through a combination of experiments and calculations.Bromo-aromatic substrates with electron-withdrawing fluoro substituents exhibited higher yields and degrees of polymerization under PPh3-assisted conditions compared to those with electron-donating or bulky methyl substituents.Additionally,excessive steric hindrance at ortho-sites or overly electrondeficient dibromoaromatic substrates leads to reaction inactivation.Calculations indicated that electron-withdrawing substituents enhanced the electrophilicity of arylpalladium-PPh3intermediates,facilitating the activation of electron-rich arylative substrates and promoting polymer growth.Furthermore,steric hindrance from the substituents can influence the preferred reaction pathway,thereby increasing the real reaction barriers.Both experimental and computational results suggest that bromoaromatic substrates with optimized electron-deficient characteristics significantly improve monomer conversion and polymerization efficiency with n-hexylmethylether-substituted EDOT.These findings clarify how the electronic and steric properties of bromo-aromatic substrates affect EDOT derivative activation and are expected to aid in optimizing the polymerization conditions for the preparation of high-molecular-weight conjugated polymers. 展开更多
关键词 3 4-Ethylenedioxythiophene Direct arylation polymerization Bromo-aromatic substrate Concerted metalation-deptonation
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Improved N_(2)selectivity for low-temperature NO_(x)reduction over etched ZSM-5 supported MnCe oxide catalysts
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作者 Shanyuan Bi Jin Zhang +4 位作者 Dengchao Peng Danhong Cheng Jianping Zhang Lupeng Han Dengsong Zhang 《Chinese Chemical Letters》 2025年第5期639-644,共6页
Developing a high-efficiency catalyst with both superior low-temperature activity and good N_(2)selectivity is still challenging for the NH_(3)selective catalytic reduction(SCR)of NO_(x)from mobile sources.Herein,we d... Developing a high-efficiency catalyst with both superior low-temperature activity and good N_(2)selectivity is still challenging for the NH_(3)selective catalytic reduction(SCR)of NO_(x)from mobile sources.Herein,we demonstrate the improved low-temperature activity and N_(2)selectivity by regulating the redox and acidic properties of MnCe oxides supported on etched ZSM-5 supports.The etched ZSM-5 enables the highly dispersed state of MnCeOx species and strong interaction between Mn and Ce species,which promotes the reduction of CeO2,facilitates electron transfer from Mn to Ce,and generates more Mn^(4+)and Ce^(3+)species.The strong redox capacity contributes to forming the reactive nitrate species and-NH_(2)species from oxidative dehydrogenation of NH_(3).Moreover,the adsorbed NH_(3)and-NH_(2)species are the reactive intermediates that promote the formation of N_(2).This work demonstrates an effective strategy to enhance the low-temperature activity and N_(2)selectivity of SCR catalysts,contributing to the NO_(x)control for the low-temperature exhaust gas during the cold-start of diesel vehicles. 展开更多
关键词 NO_(x) Selective catalytic reduction Mn-based catalyst Low-temperature activity N_(2)selectivity
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Thickness-dependent magnetic property of FeNi thin film grown on flexible graphene substrate
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作者 Suixin Zhan Shaokang Yuan +6 位作者 Yuming Bai Fu Liu Bohan Zhang Weijia Han Tao Wang Shengxiang Wang Cai Zhou 《Chinese Physics B》 2025年第2期448-452,共5页
Electronics over flexible substrates offer advantages of flexibility, portability and low cost, and promising applications in the areas of energy, information, defense science and medical service. In recent years, tre... Electronics over flexible substrates offer advantages of flexibility, portability and low cost, and promising applications in the areas of energy, information, defense science and medical service. In recent years, tremendous progress has been witnessed in the development of flexible wearable devices that can be potentially massively deployed. Of particular interest are intelligent wearable devices, such as sensors and storage cells, which can be integrated by flexible magnetoelectronic devices based on magnetic thin films. To examine this further, the magnetic properties of FeNi thin films with different thicknesses grown on flexible graphene substrate are investigated at room temperature. The coercivity increases with increasing thicknesses of FeNi thin film, which can be attributed to the increase of grain size and decrease of surface roughness. Moreover, the thickness modulated magnetic property shows a magnetic anisotropy shift increase with varying thicknesses of FeNi thin film by using measurements based on ferromagnetic resonance, which further enhances the resonance frequency. In addition, the resonance peak is quite stable after bending it for ten cycles. The result is promising for the future design of flexible magnetoelectronic devices. 展开更多
关键词 resonance frequency FeNi thin film flexible graphene substrate magnetic property
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Improved ferroelectricity in Mn-doped HfO_(2)(111)epitaxial thin films through controlled doping and substrate orientation
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作者 Jiayi Gu Haiyi Zhang +5 位作者 Weijin Pan Haifeng Bu Zhijian Shen Shengchun Shen Yuewei Yin Xiaoguang Li 《Chinese Physics B》 2025年第8期722-727,共6页
Doped HfO_(2)as an emerging ferroelectric material,holds considerable promise for non-volatile memory applications.Epitaxial growth of doped HfO_(2)thin films is widely adopted as an effective technique for revealing ... Doped HfO_(2)as an emerging ferroelectric material,holds considerable promise for non-volatile memory applications.Epitaxial growth of doped HfO_(2)thin films is widely adopted as an effective technique for revealing the intrinsic ferroelectric properties.In this study,based on systematic structural,chemical and electrical investigations,the influences of Mn doping and substrate orientation on ferroelectric properties of Mn-doped HfO_(2)epitaxial thin films are investigated.The results demonstrate that Mn-doped HfO_(2)thin films with orthorhombic phase can be epitaxially grown along[111]out-of-plane direction on both SrTiO_(3)(001)and(110)substrates,and 10%Mn-doping significantly stabilizes the orthorhombic polar phase and enhances the ferroelectric polarization.Interestingly,compared to the films on SrTiO_(3)(001)substrate,the better crystallinity and reduction of oxygen vacancy amount in Mn-doped HfO_(2)films grown on the SrTiO_(3)(110)substrate are observed,which enhance the remanent polarization and reduce the coercive field.It provides an effective approach for the controllable regulation of defects and the enhancement of intrinsic ferroelectricity in HfO_(2)-based materials. 展开更多
关键词 HfO_(2)-based ferroelectric substrate orientation FERROELECTRICITY DEFECTS
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Confined electric field in nano-sized channels of ionic porous framework towards unique adsorption selectivity
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作者 Congyan Liu Xueyao Zhou +2 位作者 Fei Ye Bin Jiang Bo Liu 《Chinese Chemical Letters》 2025年第2期437-441,共5页
Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing selectivity.They are... Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing selectivity.They are highly susceptible to framework charge,which plays a significant role in selective adsorption.Currently,ionic porous frameworks can be divided into two types.One of them is composed of a charged backbone and counter ions.The framework with zwitterionic channels is another type.It is composed of regular and alternating arrangements of cationic and anionic building units.Herein,we report a hydrogen-bonded ionic framework(HIF)of{(CN_(3)H_(6))_(2)[Ti(μ_(2)-O)(SO_(4))_(2)]}_nwith 1D channel exhibits unique adsorption selectivity for Ar against N_(2)and CO_(2).Density functional theory(DFT)results suggest that CO_(2)cannot be adsorbed by HIF at the experimental temperature due to a positive adsorption free energy.In addition,due to a relatively large diffusion barrier at 77 K,N_(2)molecules hardly diffuse in HIF channels,while Ar has a negligible diffusion barrier.The unique net positively-charged space in the channel is the key to the unusual phenomena,based on DFT simulations and structural analysis.The findings in this work proposes the new adsorption mechanism and provides unique perspective for special separation applications,such as isotope and noble gasses separations. 展开更多
关键词 Adsorption selectivity Channel Positive electric field GUANIDINIUM
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Buckling morphology evolution of thin films on non-linear elastic substrates
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作者 Andi Lai Di Ou +1 位作者 Jun Liao Guo Fu 《Acta Mechanica Sinica》 2025年第2期176-183,共8页
Organisms have evolved a strain limiting mechanism,reflected as a non-linear elastic constitutive,to prevent large deformations from threatening soft tissue integrity.Compared with linear elastic substrates,the wrinkl... Organisms have evolved a strain limiting mechanism,reflected as a non-linear elastic constitutive,to prevent large deformations from threatening soft tissue integrity.Compared with linear elastic substrates,the wrinkle of films on non-linear elastic substrates has received less attention.In this article,a unique wrinkle evolution of the film-substrate system with a J-shaped non-linear stress-strain relation is reported.The result shows that a concave hexagonal array pattern is formed with the shrinkage strain of the film-substrate systems developing.As the interconnection of hexagonal arrays,a unit cell ridge network appears with properties such as chirality and helix.The subparagraph maze pattern formed with high compression is mainly composed of special single-cell ridge networks such as spiral single cores,chiral double cores,and combined multi-cores.This evolutionary model is highly consistent with the results of experiments,and it also predicts wrinkle morphology that has not yet been reported.These findings can serve as a novel explanation for the surface wrinkle of biological soft tissue,as well as provide references for the preparation of artificial biomaterials and programmable soft matter. 展开更多
关键词 Non-linear elastic substrate Chiral ridge Spiral unit cell Tension-compression asymmetry Wrinkle morphological evolution
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Food selectivity and autism:A systematic review
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作者 Rosaria Ferrara Leonardo Iovino +3 位作者 Lidia Ricci Angiola Avallone Roberto Latina Pasquale Ricci 《World Journal of Clinical Pediatrics》 2025年第3期272-280,共9页
BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental disorder that manifests in the first years of life,with a complex pathogenesis influenced by biological,genetic and epigenetic factors.Many children with... BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental disorder that manifests in the first years of life,with a complex pathogenesis influenced by biological,genetic and epigenetic factors.Many children with ASD display marked food selectivity,often restricting themselves to a narrow range of foods.The problems associated with feeding children with ASD can vary widely,from mild cases that pose no immediate health risks,to more severe situations with a risk of mal-nutrition or,conversely,overeating.This scoping review aims to provide an in-depth overview of the frequency,nature and factors related to food selectivity in children with autism.AIM To comprehensively review the literature on food selectivity in ASD.METHODS A systematic review of the literature was conducted using the PubMed,Web of Science and EBSCO databases,to identify articles published in English from 2014 until 2024.Studies on a sample diagnosed with ASD and food selectivity were included.The selected databases were chosen for their broad coverage of the scientific literature.These databases represent reliable sources of high-quality articles,ensuring a comprehensive and up-to-date search.RESULTS We evaluated 222 studies on food selectivity in autism,from which duplicates were removed and unrelated titles were filtered out.Finally,9 articles were included in the review.Five articles provide a general overview of the phenomenon,analysing its nature and factors.Two studies delve into sensory sensitivity,in particular the impact of food textures,tastes and smells.Finally,two studies focus on problem behaviour during mealtimes.CONCLUSION Children with ASD have greater food selectivity than the neurotypical population.The diet should contain a greater variety of fruit,vegetables,yoghurt,while reducing the consumption of rice and pasta. 展开更多
关键词 Food selectivity AUTISM DEVELOPMENT Autism spectrum disorder CHILDREN
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Controlling nanomaterial distribution and aggregation in thin-film nanocomposite membranes: Role of substrate pore's relative size with nanomaterials
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作者 Siyu Cao Yufei Shu +5 位作者 Li Wang Qi Han Meng Zhang Mengxia Wang How Yong Ng Zhongying Wang 《Chinese Chemical Letters》 2025年第10期524-531,共8页
Thin-film nanocomposite(TFN) membranes have garnered considerable attention for their potential to improve separation performance by incorporating nanomaterials. However, challenges such as these materials' uneven... Thin-film nanocomposite(TFN) membranes have garnered considerable attention for their potential to improve separation performance by incorporating nanomaterials. However, challenges such as these materials' uneven distribution and aggregation have hindered practical applications. While prior studies have largely concentrated on modifying nanosheets for compatibility with polymer matrices, the role of substrate pore size in influencing nanosheet distribution has been overlooked. In this work, MoS_(2) nanosheets were dispersed in an aqueous phase to fabricate TFN membranes, investigating the effect of substrate pore size relative to the nanosheets. By systematically varying the particle size of MoS_(2) and the pore size of the substrate, we reveal how these factors impact material distribution and structural uniformity within the membranes. Our findings reveal that larger substrate pores allow the MoS_(2)-containing monomer solution to infiltrate more effectively, minimizing nanosheet aggregation. This enhances membrane performance by promoting better dispersion. Our results underscore the importance of considering the relative size of substrate pores and nanosheets in TFN membrane design, providing a pathway to improved material integration and higher membrane efficiency. 展开更多
关键词 NANOFILTRATION Thin-film nanocomposite(TFN)membranes substrate Pore size AGGREGATION MoS_(2)nanosheet
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