期刊文献+
共找到3,160篇文章
< 1 2 158 >
每页显示 20 50 100
Principled Pragmatism: Understanding the EU Position on Economic Relations with China
1
作者 Men Jing 《国际问题研究》 CSSCI 北大核心 2018年第3期216-230,共15页
关键词 principled PRAGMATISM he EU POSITION on ECONOMIC RELATIONS with China
在线阅读 下载PDF
Food Engineering Principle课程校企协同教学的创新探索
2
作者 周然 蔡紫晨 +1 位作者 余克志 沈恒 《中国现代教育装备》 2026年第1期138-141,共4页
本文探讨了在Food Engineering Principle课程中实施校企协同教学模式的必要性和优势。面对留学生教育中实践教学的挑战,提出了通过高校与企业的合作,引入企业技术人员参与教学,培养留学生的实践能力和理论知识应用能力。校企协同教学... 本文探讨了在Food Engineering Principle课程中实施校企协同教学模式的必要性和优势。面对留学生教育中实践教学的挑战,提出了通过高校与企业的合作,引入企业技术人员参与教学,培养留学生的实践能力和理论知识应用能力。校企协同教学模式充分发挥高校教师和企业教师各自优势,优化实践教学,提高了教学质量。实践证明,这种教学模式提高了留学生的培养水平,有利于提高我国的国际影响力。 展开更多
关键词 校企协同 留学生 Food Engineering Principle 食品工程原理
在线阅读 下载PDF
Thermally Drawn Flexible Fiber Sensors:Principles,Materials,Structures,and Applications
3
作者 ZhaoLun Zhang Yuchang Xue +7 位作者 Pengyu Zhang Xiao Yang Xishun Wang Chunyang Wang Haisheng Chen Xinghua Zheng Xin Yin Ting Zhang 《Nano-Micro Letters》 2026年第1期95-129,共35页
Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexib... Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexible fiber sensors.Through the preform-tofiber manufacturing technique,a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time.Examples include temperature,acoustic,mechanical,chemical,biological,optoelectronic,and multifunctional sensors,which operate on diverse sensing principles such as resistance,capacitance,piezoelectricity,triboelectricity,photoelectricity,and thermoelectricity.This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors.Finally,the future developments of thermally drawn fiber sensors are discussed. 展开更多
关键词 Thermally drawn fiber sensors Sensing principles Temperature sensors Mechanical sensors Multifunctional sensors
在线阅读 下载PDF
CAPGen: An MLLM-Based Framework Integrated with Iterative Optimization Mechanism for Cultural Artifacts Poster Generation
4
作者 Qianqian Hu Chuhan Li +1 位作者 Mohan Zhang Fang Liu 《Computers, Materials & Continua》 2026年第1期494-510,共17页
Due to the digital transformation tendency among cultural institutions and the substantial influence of the social media platform,the demands of visual communication keep increasing for promoting traditional cultural ... Due to the digital transformation tendency among cultural institutions and the substantial influence of the social media platform,the demands of visual communication keep increasing for promoting traditional cultural artifacts online.As an effective medium,posters serve to attract public attention and facilitate broader engagement with cultural artifacts.However,existing poster generation methods mainly rely on fixed templates and manual design,which limits their scalability and adaptability to the diverse visual and semantic features of the artifacts.Therefore,we propose CAPGen,an automated aesthetic Cultural Artifacts Poster Generation framework built on a Multimodal Large Language Model(MLLM)with integrated iterative optimization.During our research,we collaborated with designers to define principles of graphic design for cultural artifact posters,to guide the MLLM in generating layout parameters.Later,we generated these parameters into posters.Finally,we refined the posters using an MLLM integrated with a multi-round iterative optimization mechanism.Qualitative results show that CAPGen consistently outperforms baseline methods in both visual quality and aesthetic performance.Furthermore,ablation studies indicate that the prompt,iterative optimization mechanism,and design principles significantly enhance the effectiveness of poster generation. 展开更多
关键词 Aesthetic poster generation prompt engineering multimodal large language models iterative optimization design principles
在线阅读 下载PDF
Interfacial Superconductivity in the Type-Ⅲ Heterostructure SnSe_(2)/PtTe_(2)
5
作者 Jun Fan Xiao-Le Qiu +2 位作者 Ben-Chao Gong Kai Liu Zhong-Yi Lu 《Chinese Physics Letters》 2026年第1期248-264,共17页
Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems cons... Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems consisting of two insulators.Here,motivated by the emergence of an insulator-metal transition in type-Ⅲ heterostructures and the superconductivity in some“special”two-dimensional(2D)semiconductors via electron doping,we predict that the 2D heterostructure SnSe_(2)/PtTe_(2) is a model system for realizing IS by using firstprinciples calculations.Our results show that due to slight but crucial interlayer charge transfer,SnSe_(2)/PtTe_(2) turns to be a type-Ⅲ heterostructure with metallic properties and shows a superconducting transition with the critical temperature(T_(c))of 3.73 K.Similar to the enhanced electron–phonon coupling(EPC)in the electrondoped SnSe_(2) monolayer,the IS in the SnSe_(2)/PtTe_(2) heterostructure mainly originates from the metallized SnSe_(2) layer.Furthermore,we find that its superconductivity is sensitive to tensile lattice strain,forming a domeshaped superconducting phase diagram.Remarkably,at 7%biaxial tensile strain,the superconducting T_(c) can increase more than twofold(8.80 K),resulting from softened acoustic phonons at the𝑀point and enhanced EPC strength.Our study provides a concrete example for realizing IS in type-Ⅲ heterostructures,which waits for future experimental verification. 展开更多
关键词 d heterostructure condensed matter type III heterostructure PtTe interfacial superconductivity SnSe electron dopingwe first principles calculations
原文传递
High-T_(c) Nearly-Free-Electron Superconductivity in Quaternary Hydrides under Ambient Pressure
6
作者 Bin Li Zhisi Cao +4 位作者 Junjie Zhai Mian Wu Ding Chi Shengli Liu Jian Sun 《Chinese Physics Letters》 2026年第1期265-296,共32页
We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X... We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X represents transition metal elements.Systematic analysis of electronic band structures,phonon dispersions,and electron-phonon coupling reveals that substitution of MA binary metal combinations and X metal atoms can create favorable conditions for superconductivity.Mapping of superconducting critical temperatures,combined with dynamical stability analysis through phonon calculations,identifies ten superconducting candidates at ambient pressure.Among these,LiNaAgH_(6) exhibits nearly-free-electron behavior reminiscent of monovalent electron superconductors.It demonstrates exceptional superconducting properties with electron–phonon coupling λ=2.707,which yields a superconducting transition temperature T_(c) of 206.4 K using the Allen–Dynes formula.Its structural analogs MgNaPdH_(6),LiMgPdH_(6),LiMgAgH_(6),LiMgAuH_(6) all exhibit superconducting transition temperatures above 110 K.These findings advance our fundamental understanding of superconductivity in quaternary hydrides and provide guidance for rational design of new high-temperature superconducting materials. 展开更多
关键词 alkali alkaline earth elementsrespectivelyand hydride system quaternary hydrides transition metal analysis electronic band structuresphonon dispersionsand high t c superconductivity first principles calculations electron phonon coupling
原文传递
Three Parts of the Principled Consensus
7
《Beijing Review》 2008年第28期13-13,共1页
I. Cooperation Between China andJapan in the East China SeaChina and Japan have agreed throughserious consultations that the two sideswill conduct cooperation in the transitionalperiod prior to delimitation without pr... I. Cooperation Between China andJapan in the East China SeaChina and Japan have agreed throughserious consultations that the two sideswill conduct cooperation in the transitionalperiod prior to delimitation without preju-dicing their respective legal positions. 展开更多
关键词 Three Parts of the principled Consensus
原文传递
High temperature oxidation behavior of TiNbMoAlSi refractory high entropy alloy developed by electron beam additive manufacturing 被引量:3
8
作者 Zhe Li Liang Wang +9 位作者 Yong Yang Chen Liu Baoxian Su Qingda Zhang Zhiwen Li Jiaqi Huang Binbin Wang Liangshun Luo Ruirun Chen Yanqing Su 《Journal of Materials Science & Technology》 2025年第12期131-146,共16页
Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-depo... Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-deposited and remelted were developed to refine the microstructure and enhance the oxidation resistance of refractory high entropy alloy using electron beam freeform fabrication(EBF3).Finer and short-range ordering structures were observed in the remelted sample,whereas the Al-deposited sample showcased the formation of silicide and intermetallic phases.High-temperature cyclic and isothermal oxidation tests at 1000℃ were carried out.The total weight gain after 60 h of cyclic oxidation decreased by 17.49%and 30.46%for the remelted and deposited samples,respectively,compared to the as-cast state.Oxidation kinetics reveal an evident lower mass gain and oxidation rate in the treated samples.A multilayer oxide consisting of TiO_(2)+Al_(2)O_(3)+SiO_(2)+AlNbO_(4) was studied for its excellent oxidation resistance.The oxidation behavior of rutile,corundum and other oxides was analyzed using first principles calculations and chemical defect analysis.Overall,this research,which introduces novel treatments,offers promising insights for enhancing the inherent oxidation resistance of refractory high entropy alloys. 展开更多
关键词 Refractory high entropy alloy OXIDATION Electron beam freeform fabrication Multilayer oxide First principles calculations
原文传递
Ethical governance of clinical research on the brain-computer interface for mental disorders:a modified Delphi study 被引量:1
9
作者 Qing Zhang Chen Zhang +6 位作者 Haiqing Ji Jing Chen Xingchao Wang Tianhong Zhang Pinan Liu Zhen Wang Yifeng Xu 《General Psychiatry》 2025年第4期308-318,共11页
Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for ... Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for stakeholders and the entire community.Aims This study aims to establish a multidisciplinary consensus of principles for ethical governance of clinical BCI research for mental disorders and offer practical ethical guidance to stakeholders involved.Methods A systematic literature review,symposium and roundtable discussions,and a pre-Delphi(round 0)survey were conducted to form the questionnaire for the three-round modified Delphi study.Two rounds of surveys,followed by a third round of independent interviews of 25 experts from BCI-related research domains,were involved.We conducted quantitative analysis of responses and agreements among experts to reveal the consensus and differences regarding the ethical governance of mental BCI research from a multidisciplinary perspective.Results The Delphi panel emphasised important concerns of ethical review practices and ethical principles within the BCI context,identified qualified and highly influential institutions and personnel in conducting and advancing clinical BCI research,and recognised prioritised aspects in the risk-benefit evaluation.Experts expressed diverse opinions on specific ethical concerns,including concerns about invasive technology,its impact on humanity and potential social consequences.Agreement was reached that the practices of ethical governance of clinical BCI for mental disorders should focus on patient voluntariness,autonomy,long-term effects and related assessments of BCI interventions,as well as privacy protection,transparent reporting and ensuring that the research is conducted in qualified institutions with strong data security.Conclusions Ethical governance of clinical research on BCI for mental disorders should include interdisciplinary experts to balance various needs and incorporate the expertise of different stakeholders to avoid serious ethical issues.It requires scientifically grounded approaches,continuous monitoring and interdisciplinary collaboration to ensure evidence-based policies,comprehensive risk assessments and transparency,thereby promoting responsible innovations and protecting patient rights and well-being. 展开更多
关键词 modified Delphi study ethical governance mental disorders establish multidisciplinary consensus principles systematic literature reviewsymposium clinical brain computer interface interdisciplinary research ethical principles
暂未订购
Research of NOx Sensors Performance Test 被引量:1
10
作者 Zhengang Zhang Zhonggang Tang +3 位作者 Wei Gao Li Liu Cong Wang Hourui Sun 《Journal of Materials Science and Chemical Engineering》 2025年第2期23-30,共8页
NOx sensors, as a core component of diesel engine exhaust treatment system, play an important role in exhaust emission control, which can accurately and quickly detect the NOx and O2 concentration. It has become a nec... NOx sensors, as a core component of diesel engine exhaust treatment system, play an important role in exhaust emission control, which can accurately and quickly detect the NOx and O2 concentration. It has become a necessary option for the detection of existing exhaust emission standards. At present, there is limited and scattered information on knowledge and test methods of NOx sensors, the research of NOx sensors has become a challenging research topic at home and abroad. Based on these requirements, the article systematically integrates the knowledge of principle and testing methods. First of all, through introducing functional description of NOx sensors and the basic principle of NOx sensors, the relevant scholars can have an overall understanding of the product and master the operation mode of products. Secondly, the current status of performance test bench and methods of NOx sensors were described, which can contribute to having a clear understanding of the development process. After that, a new structure of NOx sensors test bench was purposed, which contains six major units including standard gas source, gas mixing unit, analyzer measurement unit, sensor measurement unit, data processing and display unit, exhaust gas treatment unit. And the test bench was validated. The experimental results show that the test bench has the advantages of high-repeatability, high reliability and low cost. And it can realize automatic detection of multiple target values, which is worthy further promotion. Thereby, the article can contribute to the development of its technology indirectly. 展开更多
关键词 NOx Sensors FUNCTION Performance Test Basic Principle
在线阅读 下载PDF
美国拜沃新款生物农药获全美50州登记,有效防治蓟马、蚜虫、粉虱等害虫
11
《农药》 北大核心 2025年第5期327-327,共1页
美国拜沃(Bio Works)的新生物杀虫剂Principle WP已获得包括加州在内美国所有50个州的登记,产品即将在美国上市。Principle WP基于活性成分球孢白僵菌Beauveria bassiana,无抗性问题,可高效防治蓟马、蚜虫、粉虱等害虫。这款制剂获准用... 美国拜沃(Bio Works)的新生物杀虫剂Principle WP已获得包括加州在内美国所有50个州的登记,产品即将在美国上市。Principle WP基于活性成分球孢白僵菌Beauveria bassiana,无抗性问题,可高效防治蓟马、蚜虫、粉虱等害虫。这款制剂获准用于室内和户外使用,可以喷洒于叶面,浇灌土壤,蘸取或空中施用。 展开更多
关键词 生物农药 拜沃 Principle WP 登记
原文传递
Effects of Sc Content on Microstructure and Thermophysical Properties of Al-xSc Alloys
12
作者 Wu Daogao Zhang Lu +8 位作者 Xu Minglei Feng Jing Li Shuan Zhang Xiaowei Wang Zhiqiang Yang Hongbo Dong Ruifeng Chen Xihao Wang Ning 《稀有金属材料与工程》 北大核心 2025年第9期2220-2230,共11页
AlScN piezoelectric films prepared by AlSc alloy sputter targets are essential materials for 5G radio frequency filters.The thermophysical properties of AlSc alloy targets are closely related to their welding processe... AlScN piezoelectric films prepared by AlSc alloy sputter targets are essential materials for 5G radio frequency filters.The thermophysical properties of AlSc alloy targets are closely related to their welding processes and applications.Al-xSc alloys(x=5,10,15,20,25,at%)were prepared by vacuum induction melting,whose purity is mainly determined by the raw materials and the production process.The results reveal that as the Sc content increases from 5at%to 20at%,the volume fraction of the Al_(3)Sc phase in the alloy increases from 26.9%to 80.2%,and the average grain size of the Al_(3)Sc phase increases from 12.9μm to 67.7μm during this period.Additionally,both the coefficient of thermal expansion(CTE)and thermal conductivity(TC)of AlSc alloys exhibit a downward trend.Based on experimental data and first-principles calculations,the effective medium theory and the Turner model effectively predict the TC and CTE of Al-xSc alloys.The optimal characteristic parameter(k0)of the Turner model is determined to be 50.The model predictions align well with the experimental results. 展开更多
关键词 AlSc alloys first principles MICROSTRUCTURE thermophysical properties
原文传递
Kazdan-Warner Problems on Compact Riemann Surfaces
13
作者 LI Jiayu ZHU Xiaobao 《数学进展》 北大核心 2025年第2期424-430,共7页
Let(M,g)be a compact Riemann surface with unit area,h a smooth function on M.The Kazdan-Warner problem is that under what kind of conditions on h the equationΔu=8π-8πhe^(u) has a solution.In this survey article,we ... Let(M,g)be a compact Riemann surface with unit area,h a smooth function on M.The Kazdan-Warner problem is that under what kind of conditions on h the equationΔu=8π-8πhe^(u) has a solution.In this survey article,we shall review the development of this problem along the variational method. 展开更多
关键词 Kazdan-Warner equation variational method blow-up analysis maximum principle sign-changing function
原文传递
Investigating Solutions in Nonlinear Evolution Equations:A Focus on Local Existence in Mixed Types
14
作者 NAFFISA Toureche Trouba FAN Long ABDELGHANI Dahou 《应用数学》 北大核心 2025年第3期691-702,共12页
With the urgent need to resolve complex behaviors in nonlinear evolution equations,this study makes a contribution by establishing the local existence of solutions for Cauchy problems associated with equations of mixe... With the urgent need to resolve complex behaviors in nonlinear evolution equations,this study makes a contribution by establishing the local existence of solutions for Cauchy problems associated with equations of mixed types.Our primary contribution is the establishment of solution existence,illuminating the dynamics of these complex equations.To tackle this challenging problem,we construct an approximate solution sequence and apply the contraction mapping principle to rigorously prove local solution existence.Our results significantly advance the understanding of nonlinear evolution equations of mixed types.Furthermore,they provide a versatile,powerful approach for tackling analogous challenges across physics,engineering,and applied mathematics,making this work a valuable reference for researchers in these fields. 展开更多
关键词 Nonlinear evolution equation Contraction mapping principle Sobolev space Dissipative system
在线阅读 下载PDF
First-principles study on the structure-property relationship of AlX and InX(X=N,P,As,Sb)
15
作者 HE Zhihao DING Jiafu +1 位作者 WANG Yunjie SU Xin 《无机化学学报》 北大核心 2025年第5期1007-1019,共13页
This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materi... This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materials for optical devices.Band structure calculations reveal that,except for InSb,all other compounds are direct bandgap semiconductors,with AlN exhibiting a bandgap of 3.245 eV.The valence band maximum of these eight compounds primarily stems from the p-orbitals of Al/In and X.In contrast,the conduction band minimum is influenced by all orbitals,with a predominant contribution from the p-orbitals.The static dielectric constant increased with the expansion of the unit cell volume.Compared to AlX and InX with larger X atoms,AlN and InN showed broader absorption spectra in the near-ultraviolet region and higher photoelectric conductance.Regarding mechanical properties,AlN and InN displayed greater shear and bulk modulus than the other compounds.Moreover,among these eight crystal types,a higher modulus was associated with a lower light loss function value,indicating that AlN and InN have superior transmission efficiency and a wider spectral range in optoelectronic material applications. 展开更多
关键词 aluminium‑based semiconductor indium‑based semiconductor first principle electronic structure optical property
在线阅读 下载PDF
Large Deviations for Fractional Stochastic Heat Equation with Gaussian Noise Rough in Space
16
作者 WANG Zhi LIU Junfeng 《数学进展》 北大核心 2025年第6期1368-1392,共25页
In this paper we study the Freidlin-Wentzell's large deviation principle for the following nonlinear fractional stochastic heat equation driven by Gaussian noise∂/∂tu^(ε)=D_(δ)^(α)(t,x)+√εσ(u^(ε)(t,x))W(t,x... In this paper we study the Freidlin-Wentzell's large deviation principle for the following nonlinear fractional stochastic heat equation driven by Gaussian noise∂/∂tu^(ε)=D_(δ)^(α)(t,x)+√εσ(u^(ε)(t,x))W(t,x),(t,x)∈[0,T]×R,where D_(δ)^(α)is a nonlocal fractional differential operator and W is the Gaussian noise which is white in time and behaves as a fractional Brownian motion with Hurst index H satisfying 3-α/4<H<1/2,in the space variable.The weak convergence approach plays an important role. 展开更多
关键词 fractional stochastic heat equation fractional Brownian motion large deviation principle weak convergence
原文传递
AGU Posts Principles to Guide-and Foster-Geoengineering Research
17
作者 Sean Cummings 《Engineering》 2025年第9期10-13,共4页
On 17 October 2024,the American Geophysical Union(AGU)in Washington,DC,USA,released the Ethical Framework Principles for Climate Intervention Research[1],a set of guidelines designed to help scientists,funders,policym... On 17 October 2024,the American Geophysical Union(AGU)in Washington,DC,USA,released the Ethical Framework Principles for Climate Intervention Research[1],a set of guidelines designed to help scientists,funders,policymakers,and private entities research and govern geoengineering technologies as ethically as possible.Commissioned in 2022 by the AGU Board of Directors and produced with internal funding only,the document advocates that geoengineering research projects fully consider all possible risks and benefits-environmental,sociocultural,and geopolitical-and include input from any groups such projects might impact. 展开更多
关键词 ethical framework environmental risks GEOENGINEERING geopolitical considerations research principles climate intervention sociocultural impacts ethical framework principles
在线阅读 下载PDF
Identification of High-Risk Populations: The Cornerstone of Effective and Cost-Efficient Cancer Screening
18
作者 Wei Cao Fei Wang Ni Li 《Biomedical and Environmental Sciences》 2025年第4期401-402,共2页
Cancer screening is a strategy focused on highrisk populations rather than universal populationwide screening, based on a comprehensive evaluation of epidemiological principles and practical feasibility. The effective... Cancer screening is a strategy focused on highrisk populations rather than universal populationwide screening, based on a comprehensive evaluation of epidemiological principles and practical feasibility. The effectiveness of screening depends on factors such as disease prevalence, as well as the sensitivity and specificity of the screening technology employed. 展开更多
关键词 epidemiological principles practical feasibility cancer screening screening technology sensitivity high risk populations disease prevalence practical feasibility epidemiological principles
暂未订购
UNCERTAINTY PRINCIPLES AND SIGNAL RECOVERY RELATED TO THE CANONICAL FOURIER-BESSEL TRANSFORM
19
作者 Jihed SAHBANI Lazhar DHAOUADI 《Acta Mathematica Scientia》 2025年第5期2190-2207,共18页
The aim of this paper is to prove another variation on the Heisenberg uncertainty principle,we generalize the quantitative uncertainty relations in n different(time-frequency)domains and we will give an algorithm for ... The aim of this paper is to prove another variation on the Heisenberg uncertainty principle,we generalize the quantitative uncertainty relations in n different(time-frequency)domains and we will give an algorithm for the signal recovery related to the canonical Fourier-Bessel transform. 展开更多
关键词 Fourier Bessel transform linear canonical transform quantitative uncertainty principles Heisenberg uncertainty principle signal recovery
在线阅读 下载PDF
上一页 1 2 158 下一页 到第
使用帮助 返回顶部