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Present and future of new systemic therapies for early and intermediate stages of hepatocellular carcinoma 被引量:3
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作者 Juan Jose Urquijo-Ponce Carlos Alventosa-Mateu +3 位作者 Mercedes Latorre-Sánchez Inmaculada Castelló-Miralles Moisés Diago Hepatology Unit 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2512-2522,共11页
Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Not... Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Notwithstanding the current deployment of treatments with curative intent(liver resection/local ablation and liver transplantation)in early and intermediate stages,a high rate of HCC recurrence persists,underscoring a pivotal clinical challenge.Emergent systemic therapies(ST),particularly immunotherapy,have demonstrate promising outcomes in terms of increase overall survival,but they are currently bound to the advanced stage of HCC.This review provides a comprehensive analysis of the literature,encompassing studies up to March 10,2024,evaluating the impact of novel ST in the early and intermediate HCC stages,specially focusing on the findings of neoadjuvant and adjuvant regimens,aimed at increasing significantly overall survival and recurrence-free survival after a treatment with curative intent.We also investigate the potential role of ST in enhancing the downstaging rate for the intermediate-stage HCC initially deemed ineligible for treatment with curative intent.Finally,we critically discuss about the current relevance of the results of these studies and the encouraging future implications of ST in the treatment schedules of early and intermediate HCC stages. 展开更多
关键词 Hepatocellular carcinoma Early stage Intermediate stage NEOADJUVANT ADJUVANT Systemic therapy
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A generalized nonlinear three-dimensional Hoek‒Brown failure criterion 被引量:2
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作者 Jiaxin Wang Shunchuan Wu +3 位作者 Haiyong Cheng Junlong Sun Xiaolong Wang Yaxi Shen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3149-3164,共16页
To understand the strengths of rocks under complex stress states,a generalized nonlinear threedimensional(3D)Hoek‒Brown failure(NGHB)criterion was proposed in this study.This criterion shares the same parameters with ... To understand the strengths of rocks under complex stress states,a generalized nonlinear threedimensional(3D)Hoek‒Brown failure(NGHB)criterion was proposed in this study.This criterion shares the same parameters with the generalized HB(GHB)criterion and inherits the parameter advantages of GHB.Two new parameters,b,and n,were introduced into the NGHB criterion that primarily controls the deviatoric plane shape of the NGHB criterion under triaxial tension and compression,respectively.The NGHB criterion can consider the influence of intermediate principal stress(IPS),where the deviatoric plane shape satisfies the smoothness requirements,while the HB criterion not.This criterion can degenerate into the two modified 3D HB criteria,the Priest criterion under triaxial compression condition and the HB criterion under triaxial compression and tension condition.This criterion was verified using true triaxial test data for different parameters,six types of rocks,and two kinds of in situ rock masses.For comparison,three existing 3D HB criteria were selected for performance comparison research.The result showed that the NGHB criterion gave better prediction performance than other criteria.The prediction errors of the strength of six types of rocks and two kinds of in situ rock masses were in the range of 2.0724%-3.5091%and 1.0144%-3.2321%,respectively.The proposed criterion lays a preliminary theoretical foundation for prediction of engineering rock mass strength under complex in situ stress conditions. 展开更多
关键词 Rock mechanics HoekeBrown criterion Failure criterion Intermediate principal stress True triaxial test Smoothness and convexity
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Pixelated non-volatile programmable photonic integrated circuits with 20-level intermediate states 被引量:1
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作者 Wenyu Chen Shiyuan Liu Jinlong Zhu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期477-487,共11页
Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum information.In this ... Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum information.In this paper,we propose pixelated programmable Si_(3)N_(4)PICs with record-high 20-level intermediate states at 785 nm wavelength.Such flexibility in phase or amplitude modulation is achieved by a programmable Sb_(2)S_(3)matrix,the footprint of whose elements can be as small as 1.2μm,limited only by the optical diffraction limit of anin-house developed pulsed laser writing system.We believe our work lays the foundation for laser-writing ultra-high-level(20 levels and even more)programmable photonic systems and metasurfaces based on phase change materials,which could catalyze diverse applications such as programmable neuromorphic photonics,biosensing,optical computing,photonic quantum computing,and reconfigurable metasurfaces. 展开更多
关键词 programmable photonic integrated circuits phase change materials multi-level intermediate states metasurfaces
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Ore-forming mechanism of Huxu Au-dominated polymetallic deposit in the Dongxiang Basin,South China:Constraints from in-situ trace elements and S-Pb isotopes of pyrite
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作者 Hongze Gao Jiajie Chen +3 位作者 Chengbiao Leng Yuhui Hu Huidan Xie Zenghua Li 《Acta Geochimica》 EI CAS CSCD 2024年第6期1223-1240,共18页
The Huxu Au-dominated polymetallic deposit is a hydrothermal deposit located in the Dongxiang volcanic basin in the middle section of the Gan-Hang tectonic belt in South China.The orebodies primarily occur within the ... The Huxu Au-dominated polymetallic deposit is a hydrothermal deposit located in the Dongxiang volcanic basin in the middle section of the Gan-Hang tectonic belt in South China.The orebodies primarily occur within the Jurassic-Cretaceous quartz diorite porphyry,while the genesis of this deposit is unclear.This study focused on geological and mineralogical characteristics,in-situ trace elements and S-Pb isotopes of three generations of pyrite of the Huxu deposit to clarify the distribution of trace elements in pyrite,ore-forming fluid and material sources,and genetic types of the deposit.The mineralization stage of the deposit can be divided into quartz-pyrite stage(S1),quartz-pyrite-hematite stage(S2),quartz-polymetallic sulfide stage(S3)and quartz-hematite stage(S4),with the corresponding pyrite being divided into three generations(Py1-Py3).in-situ trace element data of pyrite show that Au in pyrite mainly exists in the form of solid solution(Au^(+)),and the content is relatively low at all stages(0.18 ppm for Py1,0.32 ppm for Py2,0.68 ppm for Py3),while Pb and Zn mainly exist as sulfide inclusions in the pyrite.S-Pb isotopes show that the sulfur and ore-forming material of this deposit are mainly sourced from magma.The mineral association,mineral textures and trace elements in different stages of pyrite indicate that fluid boiling and fluid mixing are the key factors of native gold precipitation in S2 and S4,respectively,while water-rock interaction controlled the precipitation of Pb-Zn sulfides.These integrating with geological characteristics suggests that the deposit should be an intermediate sulfidation epithermal deposit. 展开更多
关键词 Au-dominated Polymetallic deposit Intermediate sulfidation Epithermal deposit PYRITE Trace element S-Pb isotope Tectonic belt
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The role of titanium at the interface of hematite photoanode in multisite mechanism:Reactive site or cocatalyst site?
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作者 Minfei Xie Xing Ji +6 位作者 Huaying Meng Nanbing Jiang Zhenyu Luo Qianqian Huang Geng Sun Yunhuai Zhang Peng Xiao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期77-86,共10页
Hematite(α-Fe_(2)O_(3))constitutes one of the most promising photoanode materials for oxygen evolution reaction(OER).Recent research on Fe_(2)O_(3) have found a fast OER rate dependence on surface hole density,sugges... Hematite(α-Fe_(2)O_(3))constitutes one of the most promising photoanode materials for oxygen evolution reaction(OER).Recent research on Fe_(2)O_(3) have found a fast OER rate dependence on surface hole density,suggesting a multisite reaction pathway.However,the effect of heteroatom in Fe_(2)O_(3) on the multisite mechanism is still poorly understood.Herein we synthesized Fe_(2)O_(3) on Ti substrates(Fe_(2)O_(3)/Ti)to study the oxygen intermediates of OER by light-dark electrochemical scans.We identified the Fe-OH species disappeared and Ti-OH intermediates appeared on Fe_(2)O_(3)/Ti when pH=11‒14,which significantly improved the OER performance of Fe_(2)O_(3)/Ti.Combined with the density functional theory calculations,we propose that Ti atom acts as cocatalyst site and captures proton from neighboring Fe-OH species under highly alkaline condition,thereby promoting the coupling of Fe=O and reducing the energy barrier of the non-electrochemical step.Our work provides a new insight into the role of heteroatom in OER multisite mechanism based on clarifying the reaction intermediates. 展开更多
关键词 HEMATITE Oxygen evolution reaction Multisite mechanism INTERMEDIATE Proton capture
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Accelerating lithium-sulfur battery reaction kinetics and inducing 3D deposition of Li_(2)S using interactions between Fe_(3)Se_(4)and lithium polysulfides
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作者 Yihan Lin Liheng Li +5 位作者 Longjie Tan Yongliang Li Xiangzhong Ren Peixin Zhang Chuanxin He Lingna Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期540-553,I0012,共15页
Although lithium-sulfur batteries(LSBs)exhibit high theoretical energy density,their practical application is hindered by poor conductivity of the sulfur cathode,the shuttle effect,and the irreversible deposition of L... Although lithium-sulfur batteries(LSBs)exhibit high theoretical energy density,their practical application is hindered by poor conductivity of the sulfur cathode,the shuttle effect,and the irreversible deposition of Li_(2)S.To address these issues,a novel composite,using electrospinning technology,consisting of Fe_(3)Se_(4)and porous nitrogen-doped carbon nanofibers was designed for the interlayer of LSBs.The porous carbon nanofiber structure facilitates the transport of ions and electrons,while the Fe_(3)Se_(4)material adsorbs lithium polysulfides(LiPSs)and accelerates its catalytic conversion process.Furthermore,the Fe_(3)Se_(4)material interacts with soluble LiPSs to generate a new polysulfide intermediate,Li_(x)FeS_(y)complex,which changes the electrochemical reaction pathway and facilitates the three-dimensional deposition of Li_(2)S,enhancing the reversibility of LSBs.The designed LSB demonstrates a high specific capacity of1529.6 mA h g^(-1)in the first cycle at 0.2 C.The rate performance is also excellent,maintaining an ultra-high specific capacity of 779.7 mA h g^(-1)at a high rate of 8 C.This investigation explores the mechanism of the interaction between the interlayer and LiPSs,and provides a new strategy to regulate the reaction kinetics and Li_(2)S deposition in LSBs. 展开更多
关键词 Lithium-sulfur batteries Polysulfide intermediates Li_(2)S electrodeposition INTERLAYERS Electrostatic spinning Adsorption Catalysis
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Lattice strain induced by trace Pt single atoms in nickel for accelerating industrial hydrogen evolution
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作者 Rui Yao Yun Wu +4 位作者 Kaiyang Zhang Shuhui Fan Qiang Zhao Jinping Li Guang Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期503-511,共9页
Strategically designing the electrocatalytic system and cleverly inducing strain is an effective approach to balance the cost and activity of Pt-based electrocatalysts for industrial-scale hydrogen production.Herein,w... Strategically designing the electrocatalytic system and cleverly inducing strain is an effective approach to balance the cost and activity of Pt-based electrocatalysts for industrial-scale hydrogen production.Herein,we present a unipolar pulsed electrodeposition(UPED) strategy to induce strain in the Ni lattice by introducing trace amounts of Pt single atoms(SAs)(0.22 wt%).The overpotential decreased by 183 mV at 10 mA cm^(-2) in 1.0 M KOH after introducing trace amounts of Pt_(SAs).The industrial electrolyzer,assembled with Pt_(SAs)Ni cathode and a commercial NiFeO_(x) anode,requires a cell voltage of 1.90 V to attain 1 A cm^(-2) of current density and remains stable for 280 h,demonstrating significant potential for practical applications.Spherical aberration corrected scanning transmission electron microscopy(AC-STEM),X-ray absorption(XAS),and geometric phase analysis(GPA) indicate that the introduction of trace amounts of Pt SAs induces tensile strain in the Ni lattice,thereby altering the local electronic structure and coordination environment around cubic Ni for enhancing the water decomposition kinetics and fundamentally changing the reaction pathway.The doping-strain strategy showcases conformational relationships that could offer new ideas to construct efficient hydrogen evolution reaction(HER) electrocatalysts for industrial hydrogen production in the future. 展开更多
关键词 Unipolar pulsed electrodeposition Pt single atoms Ni lattice Hydrogen evolution reaction H intermediates
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Steam reforming of acetic acid over Ni/biochar of low metal-loading:Involvement of biochar in tailoring reaction intermediates renders superior catalytic performance
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作者 Yunyu Guo Yiran Wang +5 位作者 Shu Zhang Yi Wang Song Hu Jun Xiang Walid Nabgan Xun Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期241-252,共12页
Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic behaviors.Herein,the Ni/biochar as well as... Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic behaviors.Herein,the Ni/biochar as well as two comparative catalysts,Ni/Al_(2)O_(3) and Ni/SiO_(2),with low nickel loading(2%(mass))was conducted to probe involvement of the varied carriers in the steam reforming.The results indicated that the Ni/biochar performed excellent catalytic activity than Ni/SiO_(2) and Ni/Al_(2)O_(3),as the biochar carrier facilitated quick conversion of the -OH from dissociation of steam to gasify the oxygen-rich carbonaceous intermediates like C=O and C-O-C,resulting in low coverage while high exposure of nickel species for maintaining the superior catalytic performance.In converse,strong adsorption of aliphatic intermediates over Ni/Al_(2)O_(3) and Ni/SiO_(2) induced serious coking with polymeric coke as the main type(21.5%and 32.1%,respectively),which was significantly higher than that over Ni/biochar(3.9%).The coke over Ni/biochar was mainly aromatic or catalytic type with nanotube morphology and high crystallinity.The high resistivity of Ni/biochar towards coking was due to the balance between formation of coke and gasification of coke and partially biochar with steam,which created developed mesopores in spent Ni/biochar while the coke blocked pores in Ni/Al_(2)O_(3) and Ni/SiO_(2) catalysts. 展开更多
关键词 Steam reforming Acetic acid Ni/biochar catalyst Property of coke Reaction intermediates
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Influence of acceleration stage electrode voltage on the performance of double-stage Hall effect thruster with adjustable zero magnetic point
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作者 陈龙 高维富 +5 位作者 崔作君 段萍 许雪松 阚子晨 檀聪琦 陈俊宇 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期60-69,共10页
The configuration of electrode voltage and zero magnetic point position has a significant impact on the performance of the double-stage Hall effect thruster. A 2D-3V model is established based on the two-magnetic peak... The configuration of electrode voltage and zero magnetic point position has a significant impact on the performance of the double-stage Hall effect thruster. A 2D-3V model is established based on the two-magnetic peak type double-stage Hall thruster configuration, and a particle-in-cell simulation is carried out to investigate the influences of both acceleration electrode voltage value and zero magnetic point position on the thruster discharge characteristics and performances.The results indicate that increasing the acceleration voltage leads to a larger potential drop in the acceleration stage, allowing ions to gain higher energy, while electrons are easily absorbed by the intermediate electrode, resulting in a decrease in the anode current and ionization rate. When the acceleration voltage reaches 500 V, the thrust and efficiency are maximized, resulting in a 15%increase in efficiency. After the acceleration voltage exceeds 500 V, a potential barrier forms within the channel, leading to a decrease in thruster efficiency. Further study shows that as the second zero magnetic point moves towards the outlet of the channel, more electrons easily traverse the zero magnetic field region, participating in the ionization. The increase in the ionization rate leads to a gradual enhancement in both thrust and efficiency. 展开更多
关键词 Hall thruster particle-in-cell simulation intermediate electrode zero magnetic point
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MOF-assisted Synthesis of Dual-atom Palladium Catalysts for Acetylene Semi-hydrogenation
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作者 Chen Jie Xu Yuebing +2 位作者 Qi Jian Liu Bing Liu Xiaohao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期42-52,共11页
The selective removal of trace acetylene in ethylene feed gas is of great significance in the petrochemicalindustry;however, there are still challenges in designing and developing high-performance catalysts. Here, a M... The selective removal of trace acetylene in ethylene feed gas is of great significance in the petrochemicalindustry;however, there are still challenges in designing and developing high-performance catalysts. Here, a MOFassistedencapsulation strategy was adopted for the precise synthesis of diatomic Pd2 sites on a ZnO support. When usedfor the acetylene semi-hydrogenation reaction, the dual-atom Pd2-ZnO catalyst exhibited improved catalytic performance,achieving complete conversion of acetylene at 125 °C with an 89% selectivity to ethene, as compared to Pd single-atom andnanoparticles. This enhancement was mainly attributed to the catalyst’s ability to dissociate H2 and facilitate the desorptionof intermediate C2H4. Moreover, the strong interaction between the support and the diatomic Pd sites was responsible for thecatalyst’s excellent stability during the long-term reaction. 展开更多
关键词 dual-atom palladium acetylene semi-hydrogenation MOFs hydrogen dissociation intermediate
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Magnetic resonance-guided focused ultrasound for essential tremor:a prospective,single center,single-arm study
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作者 Rui Zong Xuemei Li +10 位作者 Chunyu Yin Jianfeng He Dekang Zhang Xiangbing Bian Lichao Huang Jiayou Zhou Zhipei Ling Lin Ma Xin Lou Longsheng Pan Xinguang Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2075-2080,共6页
The safety and effectiveness of magnetic resonance-guided focused ultrasound thalamotomy has been broadly established and validated for the treatment of essential tremor.In 2018,the first magnetic resonance-guided foc... The safety and effectiveness of magnetic resonance-guided focused ultrasound thalamotomy has been broadly established and validated for the treatment of essential tremor.In 2018,the first magnetic resonance-guided focused ultrasound system in Chinese mainland was installed at the First Medical Center of the PLA General Hospital.This prospective,single center,open-label,single-arm study was part of a worldwide prospective multicenter clinical trial(ClinicalTrials.gov Identifier:NCT03253991)conducted to confirm the safety and efficacy of magnetic resonance-guided focused ultrasound for treating essential tremor in the local population.From 2019 to 2020,10 patients with medication refractory essential tremor were recruited into this open-label,single arm study.The treatment efficacy was determined using the Clinical Rating Scale for Tremor.Safety was evaluated according to the incidence and severity of adverse events.All of the subjects underwent a unilateral thalamotomy targeting the ventral intermediate nucleus.At the baseline assessment,the estimated marginal mean of the Clinical Rating Scale for Tremor total score was 58.3±3.6,and this improved after treatment to 23.1±6.4 at a 12-month follow-up assessment.A total of 50 adverse events were recorded,and 2 were defined as serious.The most common intraoperative adverse events were nausea and headache.The most frequent postoperative adverse events were paresthesia and equilibrium disorder.Most of the adverse events were mild and usually disappeared within a few days.Our findings suggest that magnetic resonance-guided focused ultrasound for the treatment of essential tremor is effective,with a good safety profile,for patients in Chinese mainland. 展开更多
关键词 efficacy essential tremor magnetic resonance-guided focused ultrasound(MRgFUS) movement disorder safety stereotactic therapy THALAMOTOMY ventral intermediate nucleus
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Core-shell mesoporous carbon hollow spheres as Se hosts for advanced Al-Se batteries
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作者 Haiping Lei Tianwei Wei +1 位作者 Jiguo Tu Shuqiang Jiao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期899-906,共8页
Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challen... Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challenges due to the dissolution of intermediate reaction products.In this work,we aim to harness the advantages of Se while reducing its limitations by preparing a core-shell mesoporous carbon hollow sphere with a titanium nitride(C@TiN)host to load 63.9wt%Se as the positive electrode material for Al-Se batteries.Using the physical and chemical confinement offered by the hollow mesoporous carbon and TiN,the obtained core-shell mesoporous carbon hollow spheres coated with Se(Se@C@TiN)display superior utilization of the active material and remarkable cycling stability.As a result,Al-Se batteries equipped with the as-prepared Se@C@TiN composite positive electrodes show an initial discharge specific capacity of 377 mAh·g^(-1)at a current density of 1000 mA·g^(-1)while maintaining a discharge specific capacity of 86.0 mAh·g^(-1)over 200 cycles.This improved cycling performance is ascribed to the high electrical conductivity of the core-shell mesoporous carbon hollow spheres and the unique three-dimensional hierarchical architecture of Se@C@TiN. 展开更多
关键词 aluminum-selenium batteries intermediate products core-shell mesoporous carbon hollow sphere cycling performance
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Enhanced anomalous Hall effect in kagome magnet YbMn_(6)Sn_(6)with intermediate-valence ytterbium
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作者 李龙飞 迟晟玮 +3 位作者 马文龙 郭凯臻 徐刚 贾爽 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期43-50,共8页
We report on the magnetization and anomalous Hall effect(AHE)in the high-quality single crystals of the kagome magnet YbMn_(6)Sn_(6),where the spins of the Mn atoms in the kagome lattice order ferromagnetically and th... We report on the magnetization and anomalous Hall effect(AHE)in the high-quality single crystals of the kagome magnet YbMn_(6)Sn_(6),where the spins of the Mn atoms in the kagome lattice order ferromagnetically and the intermediate-valence Yb atoms are nonmagnetic.The intrinsic mechanism plays a crucial role in the AHE,leading to an enhanced anomalous Hall conductivity(AHC)compared with the other rare-earth RMn_(6)Sn_(6)compounds.Our band structure calculation reveals a strong hybridization between the 4f electrons of Yb and conduction electrons. 展开更多
关键词 anomalous Hall effect kagome magnet intermediate valence
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Retrospective and prospective review of the generalized nonlinear strength theory for geomaterials
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作者 Shunchuan Wu Jiaxin Wang +3 位作者 Shihuai Zhang Shigui Huang Lei Xia Qianping Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1767-1787,共21页
Strength theory is the basic theory for calculating and designing the strength of engineering materials in civil,hydraulic,mechanical,aerospace,military,and other engineering disciplines.Therefore,the comprehensive st... Strength theory is the basic theory for calculating and designing the strength of engineering materials in civil,hydraulic,mechanical,aerospace,military,and other engineering disciplines.Therefore,the comprehensive study of the generalized nonlinear strength theory(GNST)of geomaterials has significance for the construction of engineering rock strength.This paper reviews the GNST of geomaterials to demonstrate the research status of nonlinear strength characteristics of geomaterials under complex stress paths.First,it systematically summarizes the research progress of GNST(classical and empirical criteria).Then,the latest research the authors conducted over the past five years on the GNST is introduced,and a generalized three-dimensional(3D)nonlinear Hoek‒Brown(HB)criterion(NGHB criterion)is proposed for practical applications.This criterion can be degenerated into the existing three modified HB criteria and has a better prediction performance.The strength prediction errors for six rocks and two in-situ rock masses are 2.0724%-3.5091%and 1.0144%-3.2321%,respectively.Finally,the development and outlook of the GNST are expounded,and a new topic about the building strength index of rock mass and determining the strength of in-situ engineering rock mass is proposed.The summarization of the GNST provides theoretical traceability and optimization for constructing in-situ engineering rock mass strength. 展开更多
关键词 rock mechanics rock mass strength strength theory failure criterion Hoek-Brown criterion intermediate principal stress deviatoric plane smoothness and convexity
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Regulating^(*)COOH intermediate via amino alkylation engineering for exceptionally effective photocatalytic CO_(2) reduction
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作者 Chengcheng Chen Qiaoyu Zhang +3 位作者 Fangting Liu Zhengguo Zhang Qiong Liu Xiaoming Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期282-291,共10页
Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate ... Photocatalytic reduction of CO_(2) into fuel represents a promising approach for achieving carbon neutrality,while realizing high selectivity in this process is challenging due to uncontrollable reaction intermediate and retarded desorption of target products.Engineering the interface microenvironment of catalysts has been proposed as a strategy to exert a significant influence on reaction outcomes,yet it remains a significant challenge.In this study,amino alkylation was successfully integrated into the melem unit of polymeric carbon nitrides(PCN),which could efficiently drive the photocatalytic CO_(2) reduction.Experimental characterization and theoretical calculations revealed that the introduction of amino alkylation lowers the energy barrier for CO_(2) reduction into^(*)COOH intermediate,transforming the adsorption of^(*)COOH intermediate from the endothermic to an exothermic process.Notably,the as-prepared materials demonstrated outstanding performance in photocatalytic CO_(2) reduction,yielding CO_(2)at a rate of 152.8μmol h^(-1) with a high selectivity of 95.4%and a quantum efficiency of 6.6%. 展开更多
关键词 Polymeric carbonnitride Regulate intermediate Photocatalytic CO_(2)reduction Amino alkylation ^(*)COOH adsorption
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Strategic regulation of nitrogen-containing intermediates for enhanced nitrate reduction over Co_(3)O_(4)/SiC catalyst having multiple active centers
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作者 Ming-Hao Guan Hao-Nan Xu +2 位作者 Jin Liu Tao Wu An-Hui Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期291-299,共9页
Regulating the intermediates involved in the electrocatalytic nitrate reduction reaction(NO_(3)RR)is crucial for the enhancement of reaction efficiency.However,it remains a great challenge to regulate the reaction int... Regulating the intermediates involved in the electrocatalytic nitrate reduction reaction(NO_(3)RR)is crucial for the enhancement of reaction efficiency.However,it remains a great challenge to regulate the reaction intermediates through active site manipulation on the surface of the catalyst.Here,a family of n%-Co_(3)O_(4)/SiC(n=5,8,12,20)catalysts with a delicate percentage of Co^(2+)and Co^(3+)were prepared for NO_(3)RR.We found that Co^(3+)primarily acts as the active site for NO_(3)^(−)reduction to NO_(2)^(−),while Co^(2+)is responsible for the conversion of NO_(2)^(−)to NH_(3).Moreover,the conversion of these intermediates over the active sites is autonomous and separately controllable.Both processes synergistically accomplish the reduction of nitrate ions to synthesize ammonia.Combining the experimental studies and density functional theory(DFT)calculations,it is discovered the pathway(^(*)NHO→^(*)NHOH→^(*)NH_(2)OH→^(*)NH_(2)→^(*)NH_(3))is more favorable due to the lowerΔG value(0.25 eV)for the rate-limiting step(^(*)NO→^(*)NHO).The NH_(3)yield rate of 8%-Co_(3)O_(4)/SiC reached 1.08 mmol/(cm^(2)h)with a Faradaic efficiency of 96.4%at−0.89 V versus the reversible hydrogen electrode(RHE),surpassing those of most reported non-noble NO_(3)RR catalysts.This strategy not only provides an efficient catalyst for NO_(3)RR but also serves as an illustrative model for the regulation of multi-step reaction intermediates through the design of distinct active sites,thereby presenting a new approach to enhance the efficiency of intricate reactions. 展开更多
关键词 ELECTROCATALYSIS Nitratereduction Co_(3)O_(4)/SiC catalysts Intermediates control
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The study of intelligent algorithm in particle identification of heavy-ion collisions at low and intermediate energies
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作者 Gao-Yi Cheng Qian-Min Su +1 位作者 Xi-Guang Cao Guo-Qiang Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期170-182,共13页
Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the... Traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate energies.Researchers urgently need solutions to the dilemma of traditional particle identification methods.This study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate energies.Multiple intelligent algorithms,including XgBoost and TabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-ISiS)and Geant4 simulation.Tree-based machine learning algorithms and deep learning algorithms e.g.TabNet show excellent performance and generalization ability.Adding additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is nonuniform.Intelligent learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies. 展开更多
关键词 Heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance
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Assessing the range of blasting-induced cracks in the surrounding rock of deeply buried tunnels based on the unified strength theory
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作者 LI Liang CHEN Jia-jun +3 位作者 ZHAO Lian-heng HE Ke-pei HU Shi-hong LI Hua-long 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2341-2364,共24页
Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety risks.However,previous theoretical studies on the range of blasting-in... Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety risks.However,previous theoretical studies on the range of blasting-induced cracks often ignore the impact of the in-situ stress,especially that of the intermediate principal stress.The particle displacement−crack radius relationship was established in this paper by utilizing the blasthole cavity expansion equation,and theoretical analytical formulas of the stress−displacement relationship and the crack radius were derived with unified strength theory to accurately assess the range of cracks in deep surrounding rock under a blasting load.Parameter analysis showed that the crushing zone size was positively correlated with in-situ stress,intermediate principal stress,and detonation pressure,whereas negatively correlated with Poisson ratio and decoupling coefficient.The dilatancy angle-crushing zone size relationship exhibited nonmonotonic behavior.The relationships in the crushing zone and the fracture zone exhibited opposite trends under the influence of only in-situ stress or intermediate principal stress.As the in-situ stress increased from 0 to 70 MPa,the rate of change in the crack range and the attenuation rate of the peak vibration velocity gradually slowed. 展开更多
关键词 deep drilling and blasting cracks in surrounding rock unified strength theory intermediate principle stress in-situ stress cavity expansion dilatancy characteristics
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Interface optimization and defects suppression via Na F introduction enable efficient flexible Sb_(2)Se_(3) thin-film solar cells
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作者 Mingdong Chen Muhammad Ishaq +7 位作者 Donglou Ren Hongli Ma Zhenghua Su Ping Fan David Le Coq Xianghua Zhang Guangxing Liang Shuo Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期165-175,I0006,共12页
Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible devices.However,the power conversion efficiency(PCE) of f... Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible devices.However,the power conversion efficiency(PCE) of flexible Sb_(2)Se_(3) photovoltaic devices is temporarily limited by the complicated intrinsic defects and the undesirable contact interfaces.Herein,a high-quality Sb_(2)Se_(3) absorber layer with large crystal grains and benign [hkl] growth orientation can be first prepared on a Mo foil substrate.Then NaF intermediate layer is introduced between Mo and Sb_(2)Se_(3),which can further optimize the growth of Sb_(2)Se_(3)thin film.Moreover,positive Na ion diffusion enables it to dramatically lower barrier height at the back contact interface and passivate harmful defects at both bulk and heterojunction.As a result,the champion substrate structured Mo-foil/Mo/NaF/Sb_(2)Se_(3)/CdS/ITO/Ag flexible thin-film solar cell delivers an obviously higher efficiency of 8.03% and a record open-circuit voltage(V_(OC)) of 0.492 V.This flexible Sb_(2)Se_(3) device also exhibits excellent stability and flexibility to stand large bending radius and multiple bending times,as well as superior weak light photo-response with derived efficiency of 12.60%.This work presents an effective strategy to enhance the flexible Sb_(2)Se_(3) device performance and expand its potential photovoltaic applications. 展开更多
关键词 Sb_(2)Se_(3) Flexible solar cells NaF intermediate layer Interface optimization Defects suppression
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Numerical Simulation of the Parallel Gap Resistance Welding Process of a Solar Cell and Mo/Pt/Ag Interconnector
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作者 Xingyu Chen Kai Wang +4 位作者 Zhicheng Wu Bin Su Xinyu Cui Yuan Huang Zumin Wang 《Transactions of Tianjin University》 EI CAS 2024年第5期419-427,共9页
Energy for space vehicles in low Earth orbit(LEO) is mainly generated by solar arrays, and the service time of the vehicles is controlled by the lifetime of these arrays, which depends mainly on the lifetime of the in... Energy for space vehicles in low Earth orbit(LEO) is mainly generated by solar arrays, and the service time of the vehicles is controlled by the lifetime of these arrays, which depends mainly on the lifetime of the interconnects. To increase the service life of LEO satellites, molybdenum/platinum/silver(Mo/Pt/Ag) laminated metal matrix composite(LMMC) interconnectors are widely used in place of Mo/Ag LMMC and Ag interconnectors in solar arrays. A 2D thermal-electrical-mechanical coupled axisymmetric model was established to simulate the behavior of the parallel gap resistance welding(PGRW) process for solar cells and Mo/Pt/Ag composite interconnectors using the commercial software ANSYS. The direct multicoupled PLANE223 element and the contact pair elements TARGE169 and CONTA172 were employed. A transitional meshing method was applied to solve the meshing problem due to the ultrathin(1 μm) intermediate Pt layer. A comparison of the analysis results with the experimental results revealed that the best parameters were 60 W, 60 ms, and 0.0138 MPa. The voltage and current predicted by the finite element method agreed well with the experimental results. This study contributes to a further understanding of the mechanism of PGRW and provides guidance for finite element simulation of the process of welding with an ultrathin interlayer. 展开更多
关键词 Solar arrays Parallel gap resistance welding Finite element method Heat transfer coefficient Ultrathin intermediate Pt layer
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