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基于事件知识图谱的教学模式及评价体系改革探索
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作者 李源 白雨 +2 位作者 姜放放 徐继宁 王伟宾 《计算机教育》 2025年第9期218-223,共6页
针对学校现有理论或实践课的教学模式和评价体系均不能较好适用的问题,提出“三维事件驱动教学模型”,具体阐述如何在学生、教师、课程3个维度构建事件知识图谱,驱动创新整合教学模式及深化多元化评价体系,并通过实践说明改革显著提升... 针对学校现有理论或实践课的教学模式和评价体系均不能较好适用的问题,提出“三维事件驱动教学模型”,具体阐述如何在学生、教师、课程3个维度构建事件知识图谱,驱动创新整合教学模式及深化多元化评价体系,并通过实践说明改革显著提升了学生成绩与教学效果,为教育数字化的推进提供新思路。 展开更多
关键词 产教融合 教学模式 评价体系 事件知识图谱
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考虑企业时间偏好的碳配额存储与借贷机制研究
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作者 白雨 赵昕 丁黎黎 《中国管理科学》 北大核心 2025年第4期357-368,共12页
设计一套灵活有效的碳配额(Chinese emission allowances,CEAs)存储与借贷机制是碳市场亟需完善的重要内容,也是提高全社会减排效率的另一创新实践。当前,我国碳交易市场存在碳价波动集聚性和碳价上涨预期,各利益相关者随即产生的CEAs... 设计一套灵活有效的碳配额(Chinese emission allowances,CEAs)存储与借贷机制是碳市场亟需完善的重要内容,也是提高全社会减排效率的另一创新实践。当前,我国碳交易市场存在碳价波动集聚性和碳价上涨预期,各利益相关者随即产生的CEAs跨期消费需求尚无法得到满足。针对以上问题,本文设计了以碳信贷中心为媒介的CEAs存储与借贷机制,并结合时间偏好与演化博弈理论,构建了包含政府、重点排放企业和碳信贷中心三方的演化博弈模型,以探讨重点排放企业时间偏好影响下CEAs存储与借贷机制中三方主体间的策略互动及其稳定性,并进一步对比分析了成本分担、收益共享这两种政府间接调控举措的政策效果。研究结果表明:(1)重点排放企业的时间偏好越弱,越有利于推动CEAs信贷市场进入帕累托均衡状态;(2)重点排放企业CEAs现期不足且未来富余的跨期需求越强烈,碳信贷中心的CEAs存储与借贷利差、CEAs增值收益越大,越能加快推动CEAs信贷市场进入帕累托均衡状态;(3)在间接调控举措中,政府与碳信贷中心间的收益共享比例需适中,成本分担比例应提高,方能有效推动CEAs信贷市场的良性健康发展,且相比于收益共享,成本分担能更快地推动CEAs存储与借贷机制的顺利运行。研究成果为政府稳定碳价、平滑CEAs跨期供给失衡、提升全社会减排效率的创新实践提供了理论依据。 展开更多
关键词 时间偏好 碳配额存储与借贷机制 碳配额跨期消费需求 演化博弈模型
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Influence of minor cerium addition on microstructure and fluidity of as-cast Al-Cu-Mn-Mg alloy 被引量:1
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作者 Yishan Wang yu bai +3 位作者 Kaixi Jiang Wenxue Fan Puxuan Wang Hai Hao 《Journal of Rare Earths》 2025年第2期377-383,I0006,共8页
Al-Cu-Mn alloys are widely used to produce automobile components like cylinder heads and engine blocks because of their capability to retain excellent thermal and mechanical characteristics at high temperatures.Howeve... Al-Cu-Mn alloys are widely used to produce automobile components like cylinder heads and engine blocks because of their capability to retain excellent thermal and mechanical characteristics at high temperatures.However,the Al-Cu-Mn-based alloys demonstrate restricted fluidity,leading to casting defects such as shrinkage and incomplete filling.This research investigated the microstructure and fluidity of Al-4.7Cu-1.0Mn-0.5Mg(wt%)alloy with minor cerium(Ce)addition.The as-cast alloys predominantly compriseα-Al matrix,accompanied by the presence of Al_(2)Cu,Al_(6)Mn,and Al_(8)Cu_(4)Ce phases.The influence of adding Ce on the fluidity of the Al-4.7Cu-1.0Mn-0.5Mg alloy was investigated using a trispiral fluidity test mold in this research.The findings suggest that the addition of Ce within the range of 0.1 wt%to 0.5 wt%in the Al-4.7Cu-1.0Mn-0.5Mg alloy results in an enhancement in fluidity.Specifically,the alloy containing 0.4 wt%Ce exhibits a significant increase in fluidity distance,from 349.7 to 485.7 mm.This improvement can be attributed to the reduction in viscosity,the refinement of secondary dendrite arm spacing,and the modification of secondary phase particles.However,a higher concentration of Ce leads to a decrease in fluidity length,potentially due to the formation of Al_(8)Cu_(4)Ce. 展开更多
关键词 Al-Cu-Mn-Mg alloy Rare earths Ce addition MICROSTRUCTURE FLUIDITY
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Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni_(2)P for lithium-sulfur batteries 被引量:1
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作者 Lin Peng yu bai +3 位作者 Hang Li Meixiu Qu Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第1期760-769,共10页
Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish ... Lithium-sulfur (Li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox dynamics.Herein,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur conversion.The study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (LiPSs) as well as expediting the bidirectional conversion kinetics of sulfur species.Meanwhile,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes Li2S dissolution and nucleation processes.Thus,the Li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion. 展开更多
关键词 B-doped atoms P vacancies Nickel phosphide Bidirectional sulfur conversion Lithium-sulfur batteries
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Resonance analysis of^(159)Tb(n,γ)reaction based on the CSNS Back-n experiment 被引量:1
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作者 De-Xin Wang Su-Ya-La-Tu Zhang +14 位作者 Wei Jiang Jie Ren Mei-Rong Huang Jing-yu Tang Xi-Chao Ruan Hong-Wei Wang Long-Xiang Liu Xue Li Dan-Dan Niu Guo Li Gu-Fu Meng Yong-Shun Huang Zhi-Long Wang yu bai Xue Yang 《Nuclear Science and Techniques》 2025年第3期85-94,共10页
The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were... The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were performed for the neutron capture cross sections of 159Tb measured at the China Spallation Neutron Source(CSNS)backscattering white neutron beamline(Back-n)facility.The resonance parameters were extracted from the R-Matrix code SAMMY and fitted to the experimental capture yield up to the 1.2 keV resolved resonance region(RRR).The average resonance parameters were determined by performing statistical analysis on the set of the resonance parameters in the RRR.These results were used to fit the measured average capture cross sections using the FITACS code in the unresolved resonance region from 2 keV to 1 MeV.The contributions of partial waves l=0,1,2 to the average capture cross sections are reported. 展开更多
关键词 Statistical analysis Resonance parameters ^(159)Tb(n γ)cross section γ
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Electronegativity-induced modulation of polysulfide adsorption in halogen-doped Ni_(2)P to accelerate conversion kinetics for lithium-sulfur batteries
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作者 Lin Peng yu bai +2 位作者 Hang Li Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第9期190-198,I0007,共10页
Heteroatom doping has emerged as a powerful strategy to optimize the catalytic and adsorption abilities of electrocatalysts by regulating the electronic structure,thereby enabling the development of efficient electroc... Heteroatom doping has emerged as a powerful strategy to optimize the catalytic and adsorption abilities of electrocatalysts by regulating the electronic structure,thereby enabling the development of efficient electrocatalysts for lithium-sulfur(Li-S)batteries.However,the correlation between the properties of doped atoms and adsorptio n-catalytic ability,as well as the interconnection between adsorption strength and catalytic activity,remains underexplored.Herein,we employed halogen atoms(F,Cl,and Br)with different electronegativities to dope nickel phosphide(Ni_(2)P),aiming to modulate the adsorption properties toward lithium polysulfides(LiPSs).We systematically explored the relationship between the electronegativity of the doping atoms and the adsorption strength,followed by exploring the connection between adsorption and catalytic capabilities.Combined experimental and theoretical analyses reveal that doping halogen atoms effectively strengthens d-p orbital hybridization between Ni atoms and S atoms,thereby enhancing LiPSs anchoring and conversion.Specifically,the chemical adsorption capability is enhanced as the electronegativity of the doped atoms increases.Moreover,the catalytic activity presents a volcano-like trend with the enhancement of adsorption performance,wherein the activity initially increases and subsequently diminishes.Therefore,Cl-doped Ni_(2)P with moderate chemisorption ability exhibits optimal redox kinetics in bidirectional sulfur conversion.Consequently,the Li-S batteries with Cl-Ni_(2)P-separators deliver a high-rate capacity of 790 mAh g^(-1)at 5 C and achieve a remarkable areal capacity of 7.36 mAh cm^(-2)under practical conditions(sulfur loading:7.10 mg cm^(-2);electrolyte/sulfur(E/S)ratio:5μL mg^(-1)).This work uncovers the significance of achieving a balance between adsorption and catalytic capabilities,offering insights into designing efficient electrocatalysts for lithium-sulfur batteries. 展开更多
关键词 Doping halogen atoms Nickel phosphide ELECTRONEGATIVITY ADSORPTION Catalytic ability Lithium-sulfur batteries
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Anchoring oxygen on LiNi_(0.94)Co_(0.05)Mn_(0.01)O_(2)surface by coating Ti_(x)NbB_((1−x))C_(2)boosts long-cycle stability of all-solid-state lithium batteries
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作者 Jingchi Zhang Ze Hua +6 位作者 Ziqi Wu Xinting Cao Wen Yang Ruiwen Shao yu bai Zhenhua Wang Kening Sun 《Journal of Energy Chemistry》 2025年第8期183-193,共11页
To satisfy the demands of modern society for high-energy–density sulfide-based all-solid-state lithium batteries(ASSLBs),Ni-rich cathode materials have gained much attention for their high capacity and energy density... To satisfy the demands of modern society for high-energy–density sulfide-based all-solid-state lithium batteries(ASSLBs),Ni-rich cathode materials have gained much attention for their high capacity and energy density.However,their practical deployment is hindered by accelerated interface degradation and capacity decay originating from surface oxygen release and lattice oxygen activation during prolonged cycling.In this study,Ti_(x)NbB_((1−x))C_(2)was successfully coated on the surface of LiNi_(0.94)Co_(0.05)Mn_(0.01)O_(2).Density functional theory(DFT)calculations first elucidate a“point-to-point”anchoring mechanism where each surface oxygen atom coordinates with single species(Ti/Nb/B)offered by Ti_(x)NbB_((1−x))C_(2),which forms robust O–M bonds and sustain a stable interface structure.The electron energy loss spectroscopy(EELS)reveals the segregation of Ti/Nb toward subsurface layers during cycling,creating an optimized lattice oxygen coordination environment and suppressing oxygen activation.The dual oxygen stabilization mechanism dramatically improves the reversibility of phase transition and the structural stability of the Ni-rich cathode materials.Moreover,Ti_(x)NbB_((1−x))C_(2)as the protective layer decreases mechanical strain and suppresses the parasitic reactions.Consequently,the engineered cathode delivers 91%capacity retention after 1000 cycles at 0.3 C,suggesting excellent cycling stability.The research delivers a new design philosophy for the coating layer that can stabilize surface oxygen.Furthermore,the atomistic understanding of the structure–property relationship of the Ni-rich cathode materials provides valuable guidance for the future design of new cathode materials with superior structural stability in ASSLBs. 展开更多
关键词 Ni-rich cathode Ti_(x)NbB_((1−x))C_(2)coating "Point-to-point"anchoring Element segregation All-solid-state lithium batteries Long cycle stability
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Integrating clinical and molecular approaches to improve survival in esophageal squamous cell carcinoma
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作者 Qian-Cheng Du yu bai Hui Nian 《World Journal of Gastrointestinal Surgery》 2025年第5期419-421,共3页
Esophageal squamous cell carcinoma continues to pose a significant global health burden due to its aggressive nature and poor prognosis,often diagnosed at an advanced stage.This retrospective study by Ren et al aims t... Esophageal squamous cell carcinoma continues to pose a significant global health burden due to its aggressive nature and poor prognosis,often diagnosed at an advanced stage.This retrospective study by Ren et al aims to identify long-term survival outcomes and the associated risk factors for esophageal squamous cell carcinoma patients,employing Kaplan-Meier survival analysis and Cox re-gression models.The study highlights critical prognostic factors such as tumor stage,age,gender,and treatment modality.The authors emphasize the im-portance of clinical factors in predicting survival and underscore the necessity of incorporating molecular biomarkers and psychosocial elements into survival models for more accurate predictions.While the study offers valuable insights,it also points to the potential for integrating modern therapies such as chemoradio-therapy and targeted treatments to improve survival outcomes.Future research should focus on prospective cohort studies,external validation,and the de-velopment of personalized treatment strategies that combine clinical,molecular,and psychosocial factors to optimize patient care. 展开更多
关键词 Esophageal squamous cell carcinoma Survival outcomes Prognostic factors Kaplan-Meier PROGNOSIS Personalized medicine
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Targeting the Osteopontin-regulated PI3K/AKT signaling pathway:A molecular approach to overcome drug resistance and metastasis in gastrointestinal tumors
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作者 Hui Nian yu bai +7 位作者 Hong-Yang Wang Hua yu Zhi-Long Zhang Ru-Hong Shi Shu Zhang Yi-Bin Wu De-Hua Zhou Qian-Cheng Du 《World Journal of Gastrointestinal Oncology》 2025年第11期25-36,共12页
Osteopontin(OPN),a key extracellular matrix protein,promotes gastrointestinal tumor progression by activating the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)pathway.OPN enhances tumor proliferation and s... Osteopontin(OPN),a key extracellular matrix protein,promotes gastrointestinal tumor progression by activating the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)pathway.OPN enhances tumor proliferation and survival through mechanistic target of rapamycin and B-cell lymphoma 2 upregulation(e.g.,via denticleless E3 ubiquitin protein ligase homolog in hepatocellular carcinoma)and drives metastasis via PI3K/AKT-mediated epithelial-mesenchymal transition and androgen receptor(AR)activation(e.g.,via the OPN-RAN-AR axis in pancreatic cancer).Additionally,OPN induces chemoresistance by activating anti-apoptotic proteins(e.g.,XIAP via CXCR3/PI3K/AKT in colorectal cancer)and remodels the tumor microenvironment through VEGF-dependent angiogenesis and cluster of differentiation 44-PI3K/AKT-mediated immune evasion.Its interaction with TLR4,WNT,and other pathways amplifies oncogenic effects.Therapies targeting the OPN-PI3K/AKT axis(e.g.,PI3K inhibitors like LY294002)or combination treatments(e.g.,with EGFR-TKIs)show promise for reversing drug resistance.Future research should focus on OPN isoform specificity,clinical translation,and interactions with autophagy and long non-coding RNAs to refine precision therapies.This review summarizes recent advances in understanding the molecular mechanisms,therapeutic targets,and clinical challenges of the OPN-PI3K/AKT axis in gastrointestinal tumors,providing a foundation for overcoming resistance and developing precision therapies. 展开更多
关键词 OSTEOPONTIN Gastrointestinal cancers CHEMORESISTANCE Targeted therapy Tumor microenvironment remodeling
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Effect of hard-plate rolling and annealing treatment on the microstructure and mechanical properties of NbB_(2)particle-reinforced AZ91 composite
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作者 Wenxue Fan yu bai +2 位作者 Tianxin Li Hai Hao Xingguo Zhang 《Journal of Magnesium and Alloys》 2025年第5期2307-2324,共18页
In this study,a NbB_(2)/AZ91 composite exhibiting desirable mechanical properties was fabricated using a sample casting technique,followed by hard-plate rolling and short-term annealing.The effect of NbB_(2)particles ... In this study,a NbB_(2)/AZ91 composite exhibiting desirable mechanical properties was fabricated using a sample casting technique,followed by hard-plate rolling and short-term annealing.The effect of NbB_(2)particles on the microstructural evolution of the AZ91 alloy was investigated.The presence of NbB_(2)was shown to have a grain-refining effect on the AZ91 alloy and promoted dynamic recrystallization(DRX)and precipitation of fine Mg_(17)Al_(12)phases via particle-stimulated nucleation(PSN).Tensile testing revealed substantial enhancements in the ultimate tensile strength(UTS),yield strength(YS),and elongation(EL)of the as-rolled AZ91 alloy,with values of 379 MPa,292 MPa,and 14.7%,respectively,owing to the incorporation of NbB_(2)particles.Annealing led to further enhancements in EL with slight reductions in UTS and YS(360 MPa,252 MPa,and 16.8%,respectively).Owing to grain refinement and the PSN effect of the NbB_(2)particles,a significant number of geometrically necessary dislocations(GNDs)were induced in the matrix during the rolling process,which reduces the nucleation barrier and increases the number of nucleation sites for the recrystallized grains and Mg_(17)Al_(12)precipitates.Meanwhile,many residual dislocations and fine Mg_(17)Al_(12)precipitates in the as-rolled alloys were annihilated during annealing,resulting in slight grain growth and coarsening.The strengthening mechanism of the NbB_(2)/AZ91 composite are mainly associated with grain-refinement strengthening,particle-induced dislocation strengthening,strengthening resulting from mismatching coefficients of thermal expansion(CTE),and heterodeformation-induced(HDI)strengthening.Textural weakening,increased activation of non-basal slip systems,more-uniform strain patterns resulting from NbB_(2)particles,and precipitation are mainly responsible for enhancing ductility. 展开更多
关键词 Mg matrix composite NbB2 particles Hard plate rolling Microstructural evolution Strengthening mechanisms
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Solid-acid-Lewis-base interaction accelerates lithium ion transport for uniform lithium deposition
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作者 Ruofan Qi Jing Zhang +3 位作者 Wang Sun yu bai Zhenhua Wang Kening Sun 《Chinese Chemical Letters》 2025年第6期724-728,共5页
Lithium metal batteries,with their light mass anode and high theoretical specific capacity of 3860 m Ah/g,have great potential for development in achieving high energy density.However,the generation of lithium dendrit... Lithium metal batteries,with their light mass anode and high theoretical specific capacity of 3860 m Ah/g,have great potential for development in achieving high energy density.However,the generation of lithium dendrites and the loss of dead lithium pose a serious threat to the safety and long-cycle stability of batteries.Herein,we utilize the Lewis acid-base interaction principle for lithium-ion migration regulation.Through loading solid-acids onto molecular sieves to immobilize Lewis base(PF_(6^(-))),we achieve accelerated dissociation of lithium salts and successfully increase the lithium ion transference number to 0.44.Lewis acid-base interaction helps lithium metal batteries achieve more uniform lithium deposition,with an average CE improved to 92.8%.The symmetrical cells can be plated/stripped stably for more than 800 h of cycling.Full cell with high surface-loaded LFP cathode(14 mg/cm^(2))exhibits impressively high capacity retention of 90.7%after 120 cycles at 0.5 C. 展开更多
关键词 Acid-base interaction Mesoporous molecular sieve SEPARATOR Li-ion transference number Lithium metal battery
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离子液体[Bmim][BF_(4)]与氧化苯乙烯分子间相互作用及催化机理的和频振动光谱研究
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作者 孟杜娟 韩琳玉 +5 位作者 刘彩合 张悦凝 秦绪金 白羽 郭源 张贞 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期420-428,I0088-I0098,I0105,共21页
离子液体作为多用途的反应介质和催化剂,在绿色化学和可持续化学领域引起了广泛的关注.本文采用和频产生振动光谱技术,深入研究了1-丁基-3-甲基咪唑四氟硼酸盐([Bmim][BF_(4)])与苯乙烯氧化物(SO)在空气/液体界面上的相互作用:在1000~37... 离子液体作为多用途的反应介质和催化剂,在绿色化学和可持续化学领域引起了广泛的关注.本文采用和频产生振动光谱技术,深入研究了1-丁基-3-甲基咪唑四氟硼酸盐([Bmim][BF_(4)])与苯乙烯氧化物(SO)在空气/液体界面上的相互作用:在1000~3700cm^(-1)的光谱范围内,仅观察到了体系中碳氢键的振动模式.值得注意的是,研究发现苯乙烯氧化物的环氧环的取向是朝向体相的,而阳离子的咪唑环上的三个碳氢基则平行于界面表面,因此,在该体系中并未观察到阳离子与苯乙烯氧化物之间的相互作用.然而,在C-H键的振动谱中,发现CH(SO)和CH_(3)(阳离子)的振动光谱峰发生蓝移,这证明了阴离子BF4与环氧环上的CH_(2)基团之间存在相互作用,这种相互作用证实了离子液体首先催化苯乙烯氧化物并随后与CO_(2)反应的反应机制.本研究为反应界面的分子间相互作用和分子取向提供了重要的见解. 展开更多
关键词 和频振动光谱 离子液体 分子间相互作用 催化机理
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Surface decoration of mesocarbon microbeads with multifunctional TiNbO_(4-x)@C coating layer as high rate and stable anode of Li-ion batteries 被引量:1
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作者 Jia-Mei Lai Zhi-Min Zou +2 位作者 yu bai yu-Tao Xing Chun-Hai Jiang 《Rare Metals》 SCIE EI CAS CSCD 2024年第5期2053-2066,共14页
Surface modification of graphite anode with electroactive matters has been proven of a more practical strategy in enhancing the performance of Li-ion batteries than exploring alternative novel anode materials.Herein,r... Surface modification of graphite anode with electroactive matters has been proven of a more practical strategy in enhancing the performance of Li-ion batteries than exploring alternative novel anode materials.Herein,rutile TiNbO_(4-x) nanoparticles with a tunnel structure are employed as multifunctional decoration substances in combination with a carbon coating layer to improve the rate and cycle properties of mesocarbon microbeads(MCMBs).As compared to pristine MCMB,the Li^(+)diffusion coefficients of the composite anodes are enhanced due to the synergistic effect of TiNbO_(4-x)@C.Meanwhile,the overcharge and voltage polarization of the composite anodes at high rate are obviously minimized due to the current sharing effect of the high-potential TiNbO_(4-x).Moreover,the amorphous Li_(y)TiNbO_(4-x) converted from TiNbO_(4-x) in the initial lithiation process can deliver pseudocapacitive capacity to the composite anodes from the second cycle.All of these functions of TiNbO_(4-x)@Ccoating layer have directly contributed to the improved rate and cycle performance of the MCMB/TiNbO_(4-x)@C composite anodes.The one containing 12.0 wt%TiNbO_(4-x) exhibits a high reversible specific capacity of 118 m Ah·g^(-1)at 10C(1C=372 m A·g^(-1)),together with a high capacity retention of 90.9%after 300 cycles at 3C,which are all much superior to those of pristine MCMB. 展开更多
关键词 Li-ion batteries MCMB TiNbO_(4-x)@C Surface decoration Rate capability
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Design of a high sensitivity and wide range angular rate sensor based on exceptional surface
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作者 丁鑫圣 刘文耀 +7 位作者 王师贤 陶煜 周彦汝 白禹 刘来 邢恩博 唐军 刘俊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期277-286,共10页
It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low an... It is found that when the parity–time symmetry phenomenon is introduced into the resonant optical gyro system and it works near the exceptional point,the sensitivity can in theory be significantly amplified at low angular rate.However,in fact,the exceptional point is easily disturbed by external environmental variables,which means that it depends on harsh experimental environment and strong control ability,so it is difficult to move towards practical application.Here,we propose a new angular rate sensor structure based on exceptional surface,which has the advantages of high sensitivity and high robustness.The system consists of two fiber-optic ring resonators and two optical loop mirrors,and one of the resonators contains a variable ratio coupler and a variable optical attenuator.We theoretically analyze the system response,and the effects of phase and coupling ratio on the system response.Finally,compared with the conventional resonant gyro,the sensitivity of this exceptional surface angular rate sensor can be improved by about 300 times at low speed.In addition,by changing the loss coefficient in the ring resonator,we can achieve a wide range of 600 rad/s.This scheme provides a new approach for the development of ultra-high sensitivity and wide range angular rate sensors in the future. 展开更多
关键词 exceptional surface exceptional points ring resonator angular rate sensing rotational direction recognition wide operating range
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Further study on the genesis of lamellar calcite veins in lacustrine black shale--A case study of Paleogene in Dongying Depression, China
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作者 Guan-Min Wang yun-Jiao Zhang +3 位作者 Zi-yuan Yin Rui Zhu Zhi-Yao Hou yu bai 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1508-1523,共16页
Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving f... Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving forces.This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe micro-analysis.Two distinct types of calcite veins have been identified:granular calcite veins and sparry calcite veins.These two types differ significantly in color,grain structure,morphology,and inclusions.Through further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite veins.The granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite veins.These granular calcite veins were likely influenced by the reduction of sulfate bacteria.On the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter.They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion period.The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of methanogens.The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion.Veins may form rapidly or through multi-stage composite processes.Early veins are predominantly formed in situ,while late veins are a result of continuous fluid migration and convergence.Furthermore,the veins continue to undergo modification even after formation.This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors:biology,organic matter,and inorganic processes,all operating at various stages throughout the shale's diagenetic history. 展开更多
关键词 Calcite veins Shale diagenesis Material source Formation period Formation mechanism
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Functionally gradient materials for sustainable and high-energy rechargeable lithium batteries:Design principles,progress,and perspectives
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作者 Jiaojiao Deng Xiuyun Ren +7 位作者 Hai Lin Liang Hu yu bai Xiaoliang yu Jinhan Mo Qianling Zhang Feiyu Kang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期426-449,共24页
Rechargeable lithium batteries with high-capacity cathodes/anodes promise high energy densities for nextgeneration electrochemical energy storage.However,the associated limitations at various scales greatly hinder the... Rechargeable lithium batteries with high-capacity cathodes/anodes promise high energy densities for nextgeneration electrochemical energy storage.However,the associated limitations at various scales greatly hinder their practical applications.Functional gradient material(FGM)design endows the electrode materials with property gradient,thus providing great opportunities to address the kinetics and stability obstacles.To date,still no review or perspective has covered recent advancements in gradient design at multiple scales for boosting lithium battery performances.To fill this void,this work provides a timely and comprehensive overview of this exciting and sustainable research field.We begin by overviewing the fundamental features of FGM and the rationales of gradient design for improved electrochemical performance.Then,we comprehensively review FGM design for rechargeable lithium batteries at various scales,including natural or artificial solid electrolyte interphase(SEI)at the nanoscale,micrometer-scale electrode particles,and macroscale electrode films.The link between gradient structure design and improved electrochemical performance is particularly highlighted.The most recent research into constructing novel functional gradients,such as valence and temperature gradients,has also been explored.Finally,we discussed the current constraints and future scope of FGM in rechargeable lithium batteries,aiming to inspire the development of novel FGM for next-generation high-performance lithium batteries. 展开更多
关键词 Rechargeable lithium battery Functional gradient material High energy density Long cycle life Review
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Integrating remote sensing and 3-PG model to simulate the biomass and carbon stock of Larix olgensis plantation
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作者 yu bai Yong Pang Dan Kong 《Forest Ecosystems》 SCIE CSCD 2024年第4期543-555,共13页
Accurate estimations of biomass and its temporal dynamics are crucial for monitoring the carbon cycle in forest ecosystems and assessing forest carbon sequestration potentials.Recent studies have shown that integratin... Accurate estimations of biomass and its temporal dynamics are crucial for monitoring the carbon cycle in forest ecosystems and assessing forest carbon sequestration potentials.Recent studies have shown that integrating process-based models(PBMs)with remote sensing data can enhance simulations from stand to regional scales,significantly improving the ability to simulate forest growth and carbon stock dynamics.However,the utilization of PBMs for large-scale simulation of larch carbon storage distribution is still limited.In this study,we applied the parameterized 3-PG(Physiological Principles Predicting Growth)model across the Mengjiagang Forest Farm(MFF)to make broad-scale predictions of the biomass and carbon stocks of Larix olgensis plantation.The model was used to simulate average diameter at breast height(DBH)and total biomass,which were later validated with a wide range of observation data including sample plot data,forest management inventory data,and airborne laser scanning data.The results showed that the 3-PG model had relatively high accuracy for predicting both DBH and total biomass at stand and regional scale,with determination coefficients ranging from 0.78 to 0.88.Based on the estimation of total biomass,we successfully produced a carbon stock map of the Larix olgensis plantation in MFF with a spatial resolution of 20 m,which helps with relevant management advice.These findings indicate that the integration of 3-PG model and remote sensing data can well predict the biomass and carbon stock at regional and even larger scales.In addition,this integration facilitates the evaluation of forest carbon sequestration capacity and the development of forest management plans. 展开更多
关键词 3-PG model LARCH BIOMASS Carbon stock ALS
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Investigation of HO_(2) uptake mechanisms onto multiple-component ambient aerosols collected in summer and winter time in Yokohama,Japan
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作者 Jun Zhou yukiko Fukusaki +9 位作者 Kentaro Murano Tania Gautam yu bai Yoshimi Inomata Hiroaki Komatsu Mayuko Takeda Bin yuan Min Shao Yosuke Sakamoto Yoshizumi Kajii 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第3期18-29,共12页
The heterogeneous loss of HO_(2)radicals onto ambient aerosols plays an important role in tropospheric chemistry.However,sparse investigation of the dominating parameters controlling the HO_(2)uptake coefficients onto... The heterogeneous loss of HO_(2)radicals onto ambient aerosols plays an important role in tropospheric chemistry.However,sparse investigation of the dominating parameters controlling the HO_(2)uptake coefficients onto ambient aerosols(γHO_(2))has largely hindered the application of the measuredγHO_(2)to the global spatial prediction.Here we induced an offine method using LFP-LIF technique to measure the kinetics of HO_(2)uptake onto ambient aerosols collected in summertime and wintertime in Yokohama city,a regional urban site near Tokyo,Japan.By controlling the dominating parameters which infuenceγHO_(2),we were able to investigate the detailed HO_(2)uptake mechanism.We characterized the chemical composition of the collected ambient aerosols,including organics,inorganics,transition metals ions,etc.and modeledγHO_(2)using different mechanisms.Results show thatγHO_(2)increased with the increase in RH,and the aerosol states(“dry”or wet/aqueous)have large effects onγHO_(2).With fixed RH and aerosol chemical composition,γHO_(2)was highly dependent on pH and inversely correlated with[HO_(2)]_0.By combing the measuredγHO_(2)values with the modeled ones,we found that both the HO_(2)self-reaction and transition metal-catalyzed reactions should be accounted for to yield a single parameterization to predictγHO_(2),and different chemical compositions may have collective effects onγHO_(2).Results may serve for extending theγHO_(2)values measured at one observation site to different environmental conditions,which will help us to achieve more accurate modeling results concerning secondary pollutant formation(i.e.,ozone). 展开更多
关键词 HO_(2)uptake kinetics Offine method Impacting factors Mechanism
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Al-CeO_(2)-Mg refiner on grain refinement,cast fluidity and mechanical properties of AZ91 alloy
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作者 Wen-xue Fan yu bai +3 位作者 Hai Hao Bo Zhang Xing-guo Zhang Kai-xi Jiang 《China Foundry》 SCIE EI CAS CSCD 2024年第6期667-675,共9页
Grain refinement is a satisfying method to enhance the comprehensive performance of Mg alloys,and using grain refiners to improve the quality of Mg castings has become a common practice in the current casting industry... Grain refinement is a satisfying method to enhance the comprehensive performance of Mg alloys,and using grain refiners to improve the quality of Mg castings has become a common practice in the current casting industry.In this study,the effects of Al-CeO_(2)-Mg grain refiner addition on microstructure,cast fluidity,and mechanical properties of AZ91 alloy were systemically investigated by OM,SEM,DSC,TEM,sand Archimedean spiral mold fluidity test,and tensile test.The results show that the Al-CeO_(2)-Mg grain refiner has a remarkable effect on as-cast AZ91 alloy including notable grain refinement,enhancement of cast fluidity,and improvement of tensile properties.The average grain size of AZ91 alloy is refined by 63%with 1.0wt.%Al-CeO_(2)-Mg grain refiner.Meanwhile,the casting flow length of the as-cast AZ91 alloy is increased from 332 mm to 440 mm.The improvement of cast fluidity is attributed to the decreased liquidus temperature,shortening of solid-liquid two-phase temperature range,and refinement of microstructure. 展开更多
关键词 AZ91 magnesium alloy grain refiner cast fluidity mechanical properties
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Serum urate is associated with an increased risk of inflammatory bowel disease: A bidirectional Mendelian randomization study
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作者 Song Zhang Xue Fang +7 位作者 Le Kang Xiang-yu Sui Miao Liu yu-Jia Luo Shuo Fu Zhao-Shen Li Sheng-BingZhao yu bai 《World Journal of Clinical Cases》 SCIE 2024年第5期891-902,共12页
BACKGROUND Previous studies have indicated bidirectional associations between urate levels and inflammatory bowel disease(IBD),including ulcerative colitis(UC)and Crohn’s disease(CD).However,it remains unclear whethe... BACKGROUND Previous studies have indicated bidirectional associations between urate levels and inflammatory bowel disease(IBD),including ulcerative colitis(UC)and Crohn’s disease(CD).However,it remains unclear whether the observations are causal because of confounding factors.AIM To investigate the causal associations between urate levels and IBD using bidirec-tional Mendelian randomization(MR).METHODS Independent genetic variants for urate levels and IBD were selected as instru-mental variables from published genome-wide association studies(GWASs).Summary statistics for instrument-outcome associations were retrieved from three separate databases for IBD(the UK Biobank,the FinnGen database and a large GWAS meta-analysis)and one for urate levels(a large GWAS meta-analysis).MR analyses included the inverse-variance-weighted method,weighted-median estimator,MR-Egger and sensitivity analyses(MR-PRESSO).A meta-analysis was also conducted to merge the data from separate outcome databases using a fixed-effects model.RESULTS Genetically higher serum urate levels were strongly associated with an increased risk of UC[odds ratio(OR):1.95,95%confidence interval(CI):1.86-2.05]after outlier correction,and the ORs(95%CIs)for IBD and CD were 0.94(95%CI:0.86-1.03)and 0.91(95%CI:0.80-1.04),respectively.Animal studies have confirmed the positive association between urate levels and UC.Moreover,genetically predicted IBD was inversely related to urate levels(OR:0.97,95%CI:0.94-0.99).However,no association was observed between genetically influenced UC or CD and urate levels.CONCLUSION Urate levels might be risk factors for UC,whereas genetically predicted IBD was inversely associated with urate levels.These findings provide essential new insight for treating and preventing IBD. 展开更多
关键词 Inflammatory bowel disease Urate levels ANTIOXIDANT Mendelian randomization Single nucleotide polymorphism
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