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Research Progress of Ta-Nb-Hf-Zr-Ti High Entropy Alloy Superconductors
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作者 Cao Likun Yang Fang +3 位作者 Hao Qingbin Zhang Shengnan Yan Guo Zhang Pingxiang 《稀有金属材料与工程》 北大核心 2026年第4期926-940,共15页
High-entropy alloys,a novel class of materials characterized by the statistical distribution of multiple principal elements on simple crystalline lattices,have emerged as a research hotspot in materials science and co... High-entropy alloys,a novel class of materials characterized by the statistical distribution of multiple principal elements on simple crystalline lattices,have emerged as a research hotspot in materials science and condensed matter physics due to their exceptional mechanical properties and unique high-entropy characteristic.Since the discovery of the first high-entropy superconductor in 2014,exploring their superconducting performance and advantages has progressively become a frontier in scientific research.The Ta-Nb-Hf-Zr-Ti system,in particular,exhibits remarkable mechanical robustness,outstanding radiation tolerance,and superconducting performance comparable to the binary NbTi alloy,positioning it as a promising candidate for advanced applications,such as high-field superconducting magnets,superconducting electric motors,and next-generation nuclear fusion reactors.This review systematically summarized global research progress on Ta-Nb-Hf-Zr-Ti-based superconductors,aiming to provide a comprehensive reference for advancing this burgeoning field. 展开更多
关键词 high-entropy alloys Ta-Nb-Hf-Zr-Ti SUPERCONDUCTOR
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Silver chloride/chitosan‑based chloramine nanohybrid with excellent antibacterial activity:Design and structure characterization as well as Ag^(+)‑Cl^(-)synergistic antibacterial effect
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作者 ZHANG Xinzhe XU Jiarong +4 位作者 GAO Mochou LIU Yage ZHAO Yanbao CUI Jingzeng ZOU Xueyan 《无机化学学报》 北大核心 2026年第2期428-438,共11页
Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticle... Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests. 展开更多
关键词 AgCl@SiO_(2)/CTS‑Cl hybrid nanoparticle synergistic effect antibacterial activity
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Study on the Adsorption Properties of Sodium Alginate-Modified Polyacrylic Acid Composite Hydrogel for Heavy Metal Cu^(2+) in Aqueous Solution
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作者 Hui Fan Xinqiang Li 《Journal of Polymer Materials》 2026年第1期235-253,共19页
To meet the needs of the treatment of Cu^(2+)pollution in aqueous solution,the sodium alginate-modified polyacrylic acid(PAA/SA)composite hydrogel was prepared by solution polymerization with acrylic acid(AA)as monome... To meet the needs of the treatment of Cu^(2+)pollution in aqueous solution,the sodium alginate-modified polyacrylic acid(PAA/SA)composite hydrogel was prepared by solution polymerization with acrylic acid(AA)as monomer,sodium alginate(SA)as filler,N,N’-methylenebisacrylamide(MBA)as crosslinking agent,and potassium persulfate(K2S2O8)as initiator.The characterization results showed that the introduction of SA significantly improved the physical and chemical properties of PAA hydrogel materials.Scanning electron microscopy(SEM)showed that as the SA content increased,the materials gradually evolved from a dense blocky structure to a porous network.When the SA content was 10 wt%,it exhibited a fragmented layered morphology.The Brunauer Emmett Teller(BET)showed that the specific surface area reached 37.65 m2/g and the porosity increased to 12.47%.Fourier transform infrared(FTIR)spectroscopy confirmed that SA was successfully embedded into the PAA network through hydrogen bonding and ion crosslinking,and the carboxyl vibration peak shifted from 2378 to 2352 cm^(-1).Mechanical tests showed that at 10 wt%SA,the maximum stress was 13.1 kPa.The adsorption experiment showed that the equilibrium adsorption capacity of the PAA/SA hydrogel for Cu^(2+)was 11.03 mg/g,with an adsorption efficiency of 42.65%.Dynamics studies showed that the adsorption process follows a first-order kinetic model(R2=0.986-0.997),indicating a physical adsorption mechanism dominated by liquid film diffusion.Theoptimal process conditions were found to be a dosage of 1.5 g/L,and the effect of temperature on adsorption was limited.The material maintained 67.4%of its initial adsorption capacity after six adsorption-desorption cycles.These parameters are generally superior to those of similar materials reported in the literature,indicating broad application prospects.Such a kinetic and isotherm model resulted from the combined effects of functional groups,electrostatic attraction,and chelation.In practical applications,pH,ionic strength,and competing ions will affect the adsorption performance of PAA/SA composite hydrogels. 展开更多
关键词 Polyacrylic acid(PAA)hydrogel sodiumalginate(SA) solution polymerization copper ions adsorption kinetics adsorption isotherm
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Rational design of planar lamellar energetic crystals via intermolecular interaction engineering: Synergistic mechanisms for balancing energy and safety
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作者 Rupeng Bu 《Defence Technology(防务技术)》 2026年第3期280-299,共20页
Energetic materials face critical challenges in balancing energy density and safety,driving the development of low-sensitivity high-energy materials.Though vital for modern defense and civilian applications,low-sensit... Energetic materials face critical challenges in balancing energy density and safety,driving the development of low-sensitivity high-energy materials.Though vital for modern defense and civilian applications,low-sensitivity high-energy materials remain scarce,with 1,3,5-trinitro-2,4,6-triaminobenzene as the only deployed example.Planar lamellar energetic crystals,which utilize weak interlamellarπ-πstacking for mechanical energy dissipation,have shown significant promise.However,their rational design is constrained by insufficient understanding of intermolecular interaction synergy.This review synthesizes the structural features of planar lamellar energetic crystals,emphasizing three core elements:the single-atomic-thickness planar stacking architecture,the"strong intralamellar and weak interlamellar interaction"paradigm(key to balancing energy density and safety for low-sensitivity high-energy materials,LSHEMs),and the role of molecular planarity in reducing shear slip barriers.It categorizes design strategies into two frameworks:H–bonding dominated(single-component:cross-shaped assembly,strong H–bonding in high symmetric molecules;multi-component methods:tenon-and-mortise,acceptor-donor separation)and other intermolecular interactions(e.g.,π-πstacking-drivenπ-π2max model,π-hole recognition).Case studies in single/multi-component crystals confirm that these strategies tune interaction synergy to achieve target packing motifs.The review highlights that interaction engineering is pivotal for PLEC design,offering a targeted theoretical framework for rational development of LSHEMs(to address the scarcity of practical LSHEMs)and guiding future crystal engineering for energy-safety balanced systems. 展开更多
关键词 Planar lamellar energetic crystals Intermolecular interactions Crystal packing Energy-safety balance Crystal engineering
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Boosting the adsorption performance of ethanol on surface chemistry modified activated carbon fiber
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作者 Mengyan Wang Yuxuan Wang +6 位作者 Junhao Wang Yinghui Han Jianxiao Yang Suchan Yang Yuanxun Zhang Peng Huo Xin Zhang 《Journal of Environmental Sciences》 2026年第1期178-186,共9页
As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This stud... As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This study prepared surface polarity-modified ACF using the heteroatom doping method.The modified ACF possessed a richer array of strongly polar oxygen/nitrogen-containing functional groups(primarily phenolic hydroxyl and lactone groups),a larger specific surface are1,and a more developed micropore structure.The adsorption capacities of ethanol for O-ACF and N-ACF were 4.110 mmol/g and 1.698 mmol/g,respectively,which were 11.3 times and 4.7 times those of unmodified ACF.This was a significant improvement over our previous work(0.363 mmol/g).The improvement of adsorption capacity for the N-ACF was mainly due to the higher specific surface are1,greater number of micropores(more adsorption sites)and abundant existence of defects,whereas,for O-ACF,the improvement mainly relied on the abundant presence of oxygen-containing functional groups on the surface.However,water had a negative effect on the adsorption of ethanol for the modified ACF due to competitive adsorption and the disappearance of capillary condensation.It was further revealed that the adsorption process of ethanol and water was quite different.It obeyed the linear driving force(LDF)model for ethanol adsorption,however,the intraparticle diffusion(IPD)model for water adsorption. 展开更多
关键词 Activated carbon fiber(ACF) Heteroatom doping Surface polarity-modified Polar functional groups Microporous filling Linear driving force(LDF) In-particle diffusion(IPD)
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The role of Hox genes in shaping embryonic external morphology of the primitive insect Thermobia domestica(Zygentoma)
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作者 Hu-Na Lu Peiyan Zhang +9 位作者 Yifan Wang Kai Luo Ziyu Yan Mei Zeng Ya-Nan Lv Shali Bai Jiaming Zeng Sheng Li Yu Bai Yun-Xia Luan 《Insect Science》 2026年第1期131-146,共16页
Insects represent one of the most evolutionarily successful groups,with their diversity hypothesized to be related to the regulatory roles of Hox genes,a set of related genes encoding homeodomain transcription factors... Insects represent one of the most evolutionarily successful groups,with their diversity hypothesized to be related to the regulatory roles of Hox genes,a set of related genes encoding homeodomain transcription factors determining the identity of segments along the anterior-posterior axis of the embryo.However,functional insights into the roles of Hox genes in primitive ametabolous insects,which represent the critical transition from aquatic crustaceans to winged insects,have been limited.In this study,we identified complete protein-coding sequences of 10 Hox genes in the Zygentoma Thermobia domestica,and applied clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated nuclease 9(Cas 9)mediated gene knockout(KO)to decipher their functions.We found that the roles of pb,Dfd,and Scr are vital in specifying the appendages of the head in T.domestica,and these roles are relatively conserved in crustaceans and winged insects.Antp is essential for the development of the prothorax segment and the first pair of legs in T.domestica.Ubx and abd-A fully repress appendage development in the abdomen of T.domestica,which implies a functional switch from crustaceans to insects.Additionally,the role of ftz in segmenting the abdomen of T.domestica suggests it has acquired new functions in primitive insects,beyond its traditional Hox-like roles.Although KOs of lab,Hox3,and Abd-B did not result in obvious external phenotypic changes,they led to a significant decrease in hatching rates and substantial deviations in daily survival numbers compared to the negative control.These findings underscore the indispensable roles of all Hox genes during the embryonic development of T.domestica.Our study sheds new light on the functional evolution of Hox genes in ametabolous insects and enhances our understanding of the genetic underpinnings of insect development and diversification. 展开更多
关键词 EVO-DEVO firebrats Hox genes
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Organocatalytic enantioselective construction of axially chiral phosphorodithiolated styrenes
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作者 Fuxing Yang Mengjie Gong +3 位作者 Yifei Zhang Bangchi Wei Nan Huang Jun Jiang 《Chinese Chemical Letters》 2026年第1期280-284,共5页
Albeit notable endeavors in the construction of organophosphorodithioates,the direct catalytic enantioselective synthesis of organophosphorodithioates still stands for a long-lasting challenge.Herein,an efficient orga... Albeit notable endeavors in the construction of organophosphorodithioates,the direct catalytic enantioselective synthesis of organophosphorodithioates still stands for a long-lasting challenge.Herein,an efficient organocatalytic enantioselective nucleophilic addition of vinylidene ortho-quinone methide with phosphinothioic thioanhydride as nucleophilic reagent has been achieved by the dual catalysis of cinchona alkaloid-derived squaramide and 4-dimethylaminopyridine.This protocol provides a straightforward approach for accessing a variety of axially chiral phosphorodithiolated styrenes in good yields(up to 98 %yield) with high stereoselectivities(up to 97 % ee and >99:1 E/Z). 展开更多
关键词 Phosphorodithiolated styrene Axial chirality Phosphinothioic thioanhydride Vinylidene ortho-quinone methide Dual catalysis
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Efficient and controlled symmetric and asymmetric Bell-state transfers in a dissipative Jaynes-Cummings model
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作者 Qi-Cheng Wu Yu-Liang Fang +4 位作者 Yan-Hui Zhou Jun-Long Zhao Yi-Hao Kang Qi-Ping Su Chui-Ping Yang 《Chinese Physics B》 2026年第1期235-242,共8页
Realizing efficient and controlled state transfers is necessary for implementing a wide range of classical and quantum information protocols.Recent studies have demonstrated that both asymmetric and symmetric state tr... Realizing efficient and controlled state transfers is necessary for implementing a wide range of classical and quantum information protocols.Recent studies have demonstrated that both asymmetric and symmetric state transfers can be achieved by encircling an exceptional point(EP)in non-Hermitian(NH)systems.However,the application of this phenomenon has been restricted to scenarios where an EP exists in single-qubit systems and is associated with a specific type of dissipation.In this work,we demonstrate efficient and controlled symmetric and asymmetric Bell-state transfers by modulating system parameters within a Jaynes-Cummings model while accounting for atomic spontaneous emission and cavity decay.The effective suppression of nonadiabatic transitions enables a symmetric exchange of Bell states irrespective of the encircling direction.Furthermore,we report a counterintuitive finding:the presence of an EP is not indispensable for implementing asymmetric state transfers in NH systems.We achieve perfect asymmetric Bell-state transfers even in the absence of an EP by dynamically orbiting around an approximate EP.Our work presents an approach to effectively and reliably manipulate entangled states with both symmetric and asymmetric characteristics,through dissipation engineering in NH systems. 展开更多
关键词 exceptional points adiabatic Bell-state transfer chiral Bell-state transfer Jaynes-Cummings model
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QingNangTCM:a parameter-efficient fine-tuning large language model for traditional Chinese medicine
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作者 Xuming Tong Liyan Liu +7 位作者 Yanhong Yuan Xiaozheng Ding Huiru Jia Xu Yang Sio Kei Im Mini Han Wang Zhang Xiong Yapeng Wang 《Digital Chinese Medicine》 2026年第1期1-12,共12页
Objective To develop QingNangTCM,a specialized large language model(LLM)tailored for expert-level traditional Chinese medicine(TCM)question-answering and clinical reasoning,addressing the scarcity of domain-specific c... Objective To develop QingNangTCM,a specialized large language model(LLM)tailored for expert-level traditional Chinese medicine(TCM)question-answering and clinical reasoning,addressing the scarcity of domain-specific corpora and specialized alignment.Methods We constructed QnTCM_Dataset,a corpus of 100000 entries,by integrating data from ShenNong_TCM_Dataset and SymMap v2.0,and synthesizing additional samples via retrieval-augmented generation(RAG)and persona-driven generation.The dataset comprehensively covers diagnostic inquiries,prescriptions,and herbal knowledge.Utilizing P-Tuning v2,we fine-tuned the GLM-4-9B-Chat backbone to develop QingNangTCM.A multidimensional evaluation framework,assessing accuracy,coverage,consistency,safety,professionalism,and fluency,was established using metrics such as bilingual evaluation understudy(BLEU),recall-oriented understudy for gisting evaluation(ROUGE),metric for evaluation of translation with explicit ordering(METEOR),and LLM-as-a-Judge with expert review.Qualitative analysis was conducted across four simulated clinical scenarios:symptom analysis,disease treatment,herb inquiry,and failure cases.Baseline models included GLM-4-9BChat,DeepSeek-V2,HuatuoGPT-II(7B),and GLM-4-9B-Chat(freeze-tuning).Results QingNangTCM achieved the highest scores in BLEU-1/2/3/4(0.425/0.298/0.137/0.064),ROUGE-1/2(0.368/0.157),and METEOR(0.218),demonstrating a balanced and superior normalized performance profile of 0.900 across the dimensions of accuracy,coverage,and consistency.Although its ROUGE-L score(0.299)was lower than that of HuatuoGPT-II(7B)(0.351),it significantly outperformed domain-specific models in expert-validated win rates for professionalism(86%)and safety(73%).Qualitative analysis confirmed that the model strictly adheres to the“symptom-syndrome-pathogenesis-treatment”reasoning chain,though occasional misclassifications and hallucinations persisted when dealing with rare medicinal materials and uncommon syndromes. 展开更多
关键词 Large language model(LLM) Traditional Chinese medicine(TCM) Fine-tuning P-Tuning v2 Clinical decision support
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Momentum transfer collision frequencies between electrons and neutrals of astrophysical interest
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作者 YuTian Cao Jun Cui +4 位作者 RuiQi Fu WenJun Liang XiaoShu Wu TieLong Zhang HaoYu Lu 《Earth and Planetary Physics》 2026年第1期82-91,共10页
Theoretical calculations serve as an effective method for determining plasma temperatures within planetary atmospheres.To simulate plasma temperature,a comprehensive implementation of the energy equation is used,which... Theoretical calculations serve as an effective method for determining plasma temperatures within planetary atmospheres.To simulate plasma temperature,a comprehensive implementation of the energy equation is used,which is governed by five terms:conductivity,heating,cooling,adiabatic expansion,and advection.The derivations mentioned are strongly dependent on the collision cross section between electrons and other particles(e.g.,neutrals,ions).It is notable that the momentum transfer cross sections between electrons and neutrals have been updated in recent decades.However,the widely used momentum average collision cross sections between electrons and neutrals,derived from the momentum transfer cross sections,are collected in studies dating back nearly half a century.Therefore,it becomes imperative to revise the momentum average collision cross sections relevant to astrophysical contexts,based on the latest studies.In this study,we summarize the momentum average collision cross sections of 13 species common in planetary atmospheres:H,H_(2),He,O,CH_(4),H_(2)O,CO,N_(2),O_(2),Ar,CO_(2),N_(2)O,and NO_(2).All results are derived from the latest studies concerning the electron-neutral collision cross section and are compared with previous studies.Furthermore,we present a comparison of the derived total electron-neutral collision frequency at Mars between this study and previous studies.Prominent differences in the total electron-neutral collision frequency between this and prior studies support the significance of updating the momentum average collision cross section between electrons and neutrals in studying the planetary atmospheres. 展开更多
关键词 momentum transfer collision planetary atmosphere electron-neutral collision frequency
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Influence of Processing Route on the Mechanical Properties of Poly(Lactic Acid)-Poly(Caprolactone)-Basalt Fiber Composites Prepared via Planetary Extrusion
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作者 Declan Mary Colbert Eyman Manaf +9 位作者 Zeeshan Ali Steven Rowe Chris Doran Trevor Howard Vlasta Chyzna Evan Moore Alan J.Murphy Patrick Doran Golnoosh Abdeali Declan M.Devine 《Journal of Polymer Materials》 2026年第1期146-163,共18页
A comparative analysis was performed on poly(lactic acid)(PLA),poly(caprolactone)(PCL),basalt fiber(BF)composites produced using two distinct approaches:direct blending and masterbatching.The limitations of PLA-BF com... A comparative analysis was performed on poly(lactic acid)(PLA),poly(caprolactone)(PCL),basalt fiber(BF)composites produced using two distinct approaches:direct blending and masterbatching.The limitations of PLA-BF composites with regard to distribution and adhesion are well-documented,as are chemical treatment methods(addition of compatibilisers,surface treatments,silanization).This work aimed to study an industrially relevant potential solution of utilising a PCL-BF masterbatch,prepared as a 50/50 wt.%blend using planetary roller extrusion(PEX)to both improve the distribution and homogeneity of the fibers as well as provide a secondary adhesion site to facilitate improved mechanical properties of the final PLA-PCL-BF composite.The resultant materials were injection moulded to prepare ISO standard test specimens and tested on the basis of their physical properties via tensile testing,impact strength testing,flexural analysis,Fourier transforminfrared spectroscopy and water absorption capability.The results displayed that the incorporation of PCL and BF led to an increase in ductility of the composite materials,allowing for improvements in the inherent brittleness of virgin PLA.Major increases in the impact strength were achieved with the utilisation of a 25% PCL/BF masterbatch,allowing for a greater than 50%increase.As an overall observation,the use of a masterbatching process,opposed to direct blending of the constituent materials allows for a greater consistency of composite to be achieved at the expense of increased gains. 展开更多
关键词 PLA natural fibers composites planetary extrusion
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Carbon sequestration from high-BOD wastewater for efficient supercapacitor electrode
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作者 Supapit Rawisod Thi Tuong Vi Tran +5 位作者 Chanatip Samart Guoqing Guan Prasert Reubroycharoen Lalita Attanatho Yoothana Thanmongkhon Suwadee Kongparakul 《Carbon Resources Conversion》 2026年第1期84-94,共11页
Hydrothermal carbonization(HTC)is a promising techno-economic method for biomass waste valorization owing to its advantages over other thermochemical processes.This study focused on carbon sequestration from sugarcane... Hydrothermal carbonization(HTC)is a promising techno-economic method for biomass waste valorization owing to its advantages over other thermochemical processes.This study focused on carbon sequestration from sugarcane bioethanol distillery wastewater via HTC and chemical activation to produce activated carbon(AC).The resulting AC was then applied as an active material for supercapacitor electrodes.The introduction of redox molecules,such as 1,4-anthraquinone(AQ)and 9,10-phenanthrenequinone(PQ),on AC increased charge storage capability via redox transformation and enhanced the electrochemical performance of the supercapacitor elec-trode.Electrochemical testing showed that AC loaded with 16 wt%PQ achieved the highest specific capacitance of 488.21 F g^(-1) with remarkable capacitance retention of 95.3% after 1000 charge-discharge cycles.N-doped AC obtained from the HTC of wastewater and melamine presented a slightly enhanced specific capacitance.Various commercial LEDs with a voltage range of 1.8-3.0 V were illuminated simultaneously by connecting them to two series of symmetric supercapacitors,demonstrating the potential application of our proposed strategy in energy storage systems.This study proposes a simple and efficient strategy to utilize wastewater and achieve net-zero emission goals in a Bio-Circular-Green Economy model. 展开更多
关键词 Hydrothermal carbonization Bioethanol wastewater Activated carbon SUPERCAPACITOR ELECTRODE
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Enhancing multiclass brain tumor classification through automated segmentation-guided deep learning
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作者 Pattaramon Vuttipittayamongkol Phakorn Charoenthiphakorn +2 位作者 Yarida Fuangfoo Pornnapha Na Phirot Thanawat Sanosiang 《Medical Data Mining》 2026年第2期15-33,共19页
Background:Accurate classification of brain tumors from Magnetic Resonance Imaging(MRI)is essential for clinical decision-making but remains challenging due to tumor heterogeneity.Existing approaches often focus solel... Background:Accurate classification of brain tumors from Magnetic Resonance Imaging(MRI)is essential for clinical decision-making but remains challenging due to tumor heterogeneity.Existing approaches often focus solely on classification or treat segmentation and classification as separate tasks,limiting overall performance and interpretability.Methods:This study proposes an end-to-end automated framework that integrates optimized tumor localization with multiclass classification.An optimized segmentation model is first employed to generate tumor masks,which are then overlaid on MRI scans to produce attention-enhanced inputs.These inputs are subsequently used to train a convolutional neural network(CNN)classifier.Experiments were conducted on a public dataset comprising 4,237 MRI scans across four categories:normal,glioma,meningioma,and pituitary tumors.Results:Three widely used segmentation models were systematically evaluated,with an optimized U-Net achieving the best performance(accuracy=0.9939,Dice=0.8893).Segmentation-guided classification consistently improved performance across six CNN architectures,with the most notable gains observed in heterogeneous tumor types such as glioma and meningioma.Among the classifiers,EfficientNet-V2 achieved the highest performance,with an accuracy of 0.9835,precision of 0.9858,recall of 0.9804,and F1-score of 0.9828.The framework was further validated on an independent external dataset,demonstrating consistent performance and robustness across diverse MRI sources.Conclusion:The proposed framework demonstrates strong potential for multiclass brain tumor classification by effectively combining segmentation and classification.This segmentation-driven approach not only enhances predictive accuracy but also improves interpretability,making it more suitable for clinical applications. 展开更多
关键词 brain tumor classification MRI segmentation segmentation-guided CNN multiclass classification tumor localization medical imaging
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Solvation-interphase synergistic regulation empowering high-temperature and fast-charging lithium metal batteries
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作者 Liu Yang Haohan Chen +7 位作者 Yajie Hu Jinyu Tian Yupeng Feng Yuanjian Li Meng Yao Fei Li Jianping Long Anjun Hu 《Journal of Energy Chemistry》 2026年第1期444-452,I0010,共10页
Lithium metal batteries(LMBs)have emerged as pivotal energy storage solutions for electric vehicles and portable electronics.However,their operation under extreme conditions(high-temperature and fast-charging conditio... Lithium metal batteries(LMBs)have emerged as pivotal energy storage solutions for electric vehicles and portable electronics.However,their operation under extreme conditions(high-temperature and fast-charging conditions)faces significant challenges,including accelerated electrolyte decomposition,interfacial instability,and potential thermal runaway risks.To address these challenges,we present a solvation-interphase synergistic regulation strategy using 2-fluorobenzenesulfonamide(2-FBS)as a multifunctional electrolyte additive.The 2-FBS molecule effectively modulates the Li^(+)solvation structure by reducing the coordination of ethylene carbonate(EC)solvent.This transformation suppresses EC-induced parasitic reactions while scavenging superoxide radicals,thereby mitigating gas evolution at electrode interfaces.Upon preferential decomposition,2-FBS further promotes the formation of a robust LiF-Li_(3)N-Li_(2)S-rich interphase with exceptional mechanical strength(Young’s modulus:39.4 GPa).This inorganic-rich hybrid interphase simultaneously enables dendrite-free lithium plating and enhances cathode thermal stability.Consequently,2-FBS-modified electrolyte empowers LiCoO_(2)//Li cells to deliver 82.8%capacity retention after 800 cycles at 55°C and sustain 81.2%capacity retention after 1500 cycles at 4 C.Moreover,practical validation through nail penetration tests confirms the effectiveness of the electrolyte in preventing thermal propagation in fully charged pouch cells.This work establishes a paradigm for enabling reliable battery operation under extreme conditions through synergistic solvation and interphase engineering. 展开更多
关键词 Lithium-metal batteries Electrolyte additives Solvation structure Interphase regulation Pouch cells
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Diagnosis of Gearbox Typical Fault in Rolling Mills Based on the Wavelet Packets Technology
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作者 CUI Lingli GAO Lixin +1 位作者 ZHANG Jianyu DING Fang 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期1042-1045,共4页
The early impulse fault diagnosis of the gearbox in rolling mills is often difficult and labour intensive because the gearbox of that high speed machine is multi-shafting transmission system,in which many gearsets and... The early impulse fault diagnosis of the gearbox in rolling mills is often difficult and labour intensive because the gearbox of that high speed machine is multi-shafting transmission system,in which many gearsets and rolling bears work together at the same time and there are much complex frequency structure and various disturb.A new time-frequency method based on the wavelet packets technique was developed and used to extract the impact feature from signals collected from faulty data of one rolling mills gearbox.The method improves the signal to noise ration so that results obtained using this method represents features with fine resolution in both low-frequency and the high frequency bands.The results of analysis indicate the validity and the practicability of the method proposed here. 展开更多
关键词 fault diagnosis feature extraction rolling mills GEARBOX wavelet packets
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Practice of Mind Mapping Technology in"Re-flipped Classroom"Teaching Mode:A Case Study of the Course Principles of Residential District Planning
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作者 Liwen LIU Xiquan CHEN +1 位作者 Xiaoyun LI Jianrong ZHANG 《Asian Agricultural Research》 2020年第12期80-84,共5页
The present study proposed the"re-flipped classroom"teaching mode taking the course Principles of Residential District Planning as an example.Using the Small Private Online Courses(SPOCs)and Massive Open Onl... The present study proposed the"re-flipped classroom"teaching mode taking the course Principles of Residential District Planning as an example.Using the Small Private Online Courses(SPOCs)and Massive Open Online Courses(MOOCs)of the iCourse platform,with the aid of the mind mapping technology,the complex content is visualized to the information that can be easily accepted by the brain,to improve the efficiency of thinking problems and apply theories to practical teaching.The results indicate that the teaching mode combined with mind mapping technology has strong appeal,can improve teacher-student interaction,and effectively improve the teaching effects.Finally,it came up with recommendations including attaching importance to the"re-flipped classroom"teaching mode,integrating teaching methods,and using online platform resources.It is concluded that the research of teaching mode has important theoretical and practical significance for ensuring the teaching quality. 展开更多
关键词 Residential district Flipped classroom Min map Teaching reform
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Research Based on Innovation and Entrepreneurship Driven by "Four Wheels" and Combination of Professional Education and Teaching-- Taking the " Specialty of Computer Application Technology in Hunan Ap-plied Technology University" as an Example
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作者 Runmiao Zhou Xin Liu 《Modern Electronic Technology》 2018年第1期26-30,共5页
Implementing innovation and entrepreneurship education by combining with professional education in universities and colleges is an important measure to promote higher-quality employment and entrepreneurship of the gra... Implementing innovation and entrepreneurship education by combining with professional education in universities and colleges is an important measure to promote higher-quality employment and entrepreneurship of the graduates. The problems existing in the fusing teaching of computer application technology and innovation and entrepreneurship education are analyzed in this paper. By taking Hunan Applied Technology University as an example and in view of the existing problems, the mode of reform driven by "four wheels","professional talent training scheme by integrating optimization, innovation and entrepreneurship","implementing the specific teaching by integrating imovation,entrepreneurship and professional education","building many forms and university-enterprise cooperation platforms for innovation and entrepreneurship" and "setting up reasonable management and incentive mechanism for teachers and students" are proposed, to realize the dynamic integration of professional education and innovation and entrepreneurship education for the specialty of computer application technology. 展开更多
关键词 "Four-wheel" driving FUSING teaching Innovation and ENTREPRENEURSHIP education
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On the Same Floor Building Drainage Technology
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作者 LI Sufeng 《International English Education Research》 2017年第1期15-17,共3页
The same floor drainage refers to sanitary wares in the washing room, to be specific, the drainage pipe (sewage and branch pipes respectively) which can be into other houses without going through floors! This techno... The same floor drainage refers to sanitary wares in the washing room, to be specific, the drainage pipe (sewage and branch pipes respectively) which can be into other houses without going through floors! This technology has many advantages, like easy to construct and install at the same floor on one hand; on the other hand, when sewage or waste reach the top compared with the same kind drainage systems and other drainage methods, it can smoothly enter the main pipe (the chief vertical one). Moreover, once there is any situation needing dredge and cleaning, this problem can be solved at the same floor without interrupting the lives of other families. Last but not the least, it is so convenient to create a clean and tidy washing room. The branch pipe without being through floors is the very reason to solve the problem of surface condensation relative to sewage pipe in the rainy days, which correspondingly increases the hcight of head room indoor, is more favorable for fire prevention and much easier to keep smooth pipe flow. 展开更多
关键词 Drainage on same floor Hidden installation Drainage catchment Floor drain
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Application of Control Technology Based on PLC in Power Supply and Distribution System
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作者 QIAN Lina 《International English Education Research》 2015年第10期29-30,共2页
With the rapid development of China's economy, the entire social requires the safety, reliability and automation of power supply and distribution system must be improved. Therefore, extensive application of PLC techn... With the rapid development of China's economy, the entire social requires the safety, reliability and automation of power supply and distribution system must be improved. Therefore, extensive application of PLC technology in power supply and distribution system has great significance to ensure normal social life and production, so as to realize the entire national economy sustained and healthy development. This paper briefly introduces the PLC technology, and with practice elaborates the applications of control technology based on PLC in power supply and distribution system fi:om the reform of low-voltage distribution system, automation management and relay protection of power supply and distribution system etc. 展开更多
关键词 PLC control technology power supply and distribution system
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Exploration of Diversified Talent Training and Collaborative Innovation Models from the Perspective of Scientific Research Team Construction and Collaborative Management Mechanism in Applied Undergraduate Universities
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作者 Yuanmin Gao Hejian Liu +1 位作者 Yonggang Wang Luyao Dong 《Journal of Contemporary Educational Research》 2024年第12期1-8,共8页
This study is dedicated to exploring the role of scientific research team construction and collaborative management mechanisms in applied undergraduate universities in promoting diversified talent training and collabo... This study is dedicated to exploring the role of scientific research team construction and collaborative management mechanisms in applied undergraduate universities in promoting diversified talent training and collaborative innovation models.By forming an interdisciplinary scientific research team and recording in detail the team’s performance,problems encountered,and solutions during the collaborative innovation process,the study found that interdisciplinary team construction significantly improved scientific research timeliness,which was 29.33%higher than that of traditional single-disciplinary teams.Therefore,the construction of interdisciplinary scientific research teams and collaborative management mechanisms are effective ways for applied undergraduate universities to promote diversified talent training and collaborative innovation. 展开更多
关键词 Applied undergraduate Scientific research team construction Collaborative management mechanism Diversified talent training Educational model exploration
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