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Diagnostic value of mismatch-negativity and P3a event-related potentials for sepsis-associated encephalopathy in non-sedated patients:a pilot study
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作者 Zengzheng Ge Xin Lu +7 位作者 Shiyuan Yu Mubing Qin Chao Gong Qun Xu Yanxia Gao Joseph Harold Walline Huadong Zhu Yi Li 《World Journal of Emergency Medicine》 2026年第2期172-178,共7页
BACKGROUND:Although the Confusion Assessment Methods for the Intensive Care Unit(CAMICU) is a recommended tool for diagnosing sepsis-associated encephalopathy(SAE),it has several limitations.Mismatch-negativity(MMN) a... BACKGROUND:Although the Confusion Assessment Methods for the Intensive Care Unit(CAMICU) is a recommended tool for diagnosing sepsis-associated encephalopathy(SAE),it has several limitations.Mismatch-negativity(MMN) and P3a are components of event-related potentials(ERPs) used with electroencephalography(EEG) and are associated with cerebral function changes in critically ill patients.This study aimed to provide a quantitative,non-invasive method to guide SAE diagnosis in nonsedated patients.METHODS:From January 2022 to March 2023,sepsis patients without sedation were enrolled and assessed via the CAM-ICU,Glasgow Coma Scale(GCS),and ERP under standard procedures.Both MMN and P3a data were collected.The diagnostic value of MMN and P3a was assessed with processed ERP data.RESULTS:Thirty-six patients were included in this study,comprising 19 patients with SAE and 17 patients without SAE(NSAE).MMN and P3a amplitudes decreased,and only FzMMN amplitude significantly decreased in SAE patients(2.03 [1.08,2.93] mV vs.3.21 [1.92,4.34] mV,P=0.040).After median dichotomization,low F3P3a and FzP3a amplitudes were associated with higher CAM-ICU positivity rates and APACHE II scores.Both amplitude in F3P3a(AUC=0.710,95%CI:0.527–0.893,P=0.034) and FzP3a(AUC=0.700,95%CI:0.519–0.881,P=0.041) exhibited moderate diagnostic efficacy for SAE,while FzMMN amplitude lacks effective diagnostic value.CONCLUSION:In this pilot study,ERP components F3P3a and FzP3a amplitudes demonstrated moderate diagnostic value for SAE.These exploratory findings require confirmation in larger and powered cohorts. 展开更多
关键词 Sepsis-associated encephalopathy Event-related potentials Mismatch-negativity Electroencephalography Diagnostic value
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Redefining atomistic simulations of all-solid-state batteries through machine learning interatomic potentials
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作者 Qian Chen Siwen Wang Chen Ling 《Journal of Energy Chemistry》 2026年第1期666-687,I0015,共23页
All-solid-state batteries(ASSBs)represent a next-generation energy storage technology,offering enhanced safety,higher energy density,and improved cycling stability compared to conventional liquid-electrolyte-based lit... All-solid-state batteries(ASSBs)represent a next-generation energy storage technology,offering enhanced safety,higher energy density,and improved cycling stability compared to conventional liquid-electrolyte-based lithium-ion batteries.Understanding and optimizing the complex chemistries and interfaces that underpin ASSB performance present significant challenges from both experimental and modeling perspectives.In particular,atomistic simulations face difficulties in capturing the complex structure,disorder,and dynamic evolution of materials and interfaces under practically relevant conditions.While established methods such as density functional theory and classical force fields have provided valuable insights,some questions remain difficult to address,particularly those involving large system sizes or long timescales.Recently,machine learning interatomic potentials(MLIPs)have emerged as a transformative tool,enabling atomistic simulations at length and time scales that were previously challenging to access with conventional approaches.By delivering near first-principles accuracy with much greater efficiency,MLIPs open new avenues for large-scale,long-timescale,and high-throughput simulations of solid-state battery materials.In this review,we present a comparative overview of density functional theory,classical force fields,and MLIPs,highlighting their respective strengths and limitations in ASSB research.We then discuss how MLIPs enable simulations that reach longer timescales,larger system sizes,and support high-throughput calculations,providing unique insights into ion transport and interfacial evolution in ASSBs.Finally,we conclude with a summary and outlook on current challenges and future opportunities for expanding MLIP capabilities and accelerating their impact in solid-state battery research. 展开更多
关键词 All-solid-state batteries Solid-state electrolytes Machine-learning interatomic potential Atomistic modeling lon transport INTERFACES
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Study of event-related potentials to identify differences in verbal working memory in patients with mild cognitive impairment with different Traditional Chinese Medicine syndromes
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作者 LIU Yong HOU Junlin +5 位作者 ZHAO Ziwei YAN Guoli LI Ning ZHAO Chun ZHAN Xianghong ZHOU Liyue 《Journal of Traditional Chinese Medicine》 2026年第1期211-218,共8页
OBJECTIVE:To examine the differences in cognitive processing between patients with mild cognitive impairment(MCI)of different Traditional Chinese Medicine(TCM)syndrome types to provide evidence supporting the TCM typi... OBJECTIVE:To examine the differences in cognitive processing between patients with mild cognitive impairment(MCI)of different Traditional Chinese Medicine(TCM)syndrome types to provide evidence supporting the TCM typing of MCI.METHODS:Participants were screened using a battery of scales for spleen and kidney deficiency(SKD)/liver Qi stagnation(LQS)-type MCI or those without syndrome or normal control(NC).Following sex,age,and educational matching,behavioral and electroencephalographic data were recorded using the verbal N-back experimental paradigm.The data were then analyzed and compared with respect to the reaction time and correctness of the participants in each group,as well as the amplitude and latency of the event-related potential(ERP)components of P2,N2,and P3.RESULTS:There were no statistically significant differences in the accuracy or reaction times of the behavioral data of the groups.Regarding ERP data,the SKD group had a shorter P2 latency than the LQS and NC groups,while the latter two groups did not differ statistically.The SKD group had a shorter N2 latency than the NC group,while the SKD group did not differ from the LQS group.The SKD and LQS groups had a shorter P3 latency than the NC group.CONCLUSION:Our study offers objective evidence of the distinction between the types of TCM syndrome.Different types of TCM syndromes produce different disease mechanisms,resulting in brain damage with different presentations of cognitive impairment and cognitive processing characteristics. 展开更多
关键词 mild cognitive impairment Traditional Chinese Medicine syndrome types event-related potential N-back paradigm
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Natural Tourism in Kosovo and the Potentials of the Dukagjin Region
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作者 Alberta Tahiri Anela Džogović +13 位作者 Idriz Kovaçi Thëllëza Latifi Sadrija Nora Draga Elvira Misini Ardiana Hyseni Selvije Lajqi Doresa Mulaj Fatbardha Shala Hyrije Bajramaj Kushtrim Agaj Flaka Muriqi Mimoza Mekuli Ismet Berisha Mendim Nimonaj 《Journal of Environmental & Earth Sciences》 2025年第3期274-285,共12页
This study aims to assess the potential of natural tourism in Kosovo,especially in the Dukagjin region as a case study.The main objective is to identify and analyze this region’s tourism potential to understand its i... This study aims to assess the potential of natural tourism in Kosovo,especially in the Dukagjin region as a case study.The main objective is to identify and analyze this region’s tourism potential to understand its impact and importance.180 respondents from the Dukagjin region participated in this study,and the quantitative method was used as a methodology.The measurement instrument consisted of 30 closed questions,which aimed to collect detailed information on the potential of natural tourism in this area.The study results showed that mountain,cultural,winter,healing,and rural tourism are especially important for developing the Dukagjin region.Furthermore,the analysis shows that 30%of the tourism potential is explained by rural tourism,underlining its importance in the local economy.Finally,the study’s findings are discussed,emphasizing their practical value for promoting and developing sustainable tourism in the region. 展开更多
关键词 Development Dukagjin Region Natural Tourism Rural Tourism Tourist potentials Tourism Promotion
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Delocalized Nonlinear Vibrational Modes in Bcc Lattice for Testing and Improving Interatomic Potentials
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作者 Denis S.Ryabov IgorV.Kosarev +2 位作者 Daxing Xiong Aleksey A.Kudreyko Sergey V.Dmitriev 《Computers, Materials & Continua》 2025年第3期3797-3820,共24页
Molecular dynamics(MD)is a powerful method widely used in materials science and solid-state physics.The accuracy of MD simulations depends on the quality of the interatomic potentials.In this work,a special class of e... Molecular dynamics(MD)is a powerful method widely used in materials science and solid-state physics.The accuracy of MD simulations depends on the quality of the interatomic potentials.In this work,a special class of exact solutions to the equations of motion of atoms in a body-centered cubic(bcc)lattice is analyzed.These solutions take the form of delocalized nonlinear vibrational modes(DNVMs)and can serve as an excellent test of the accuracy of the interatomic potentials used in MD modeling for bcc crystals.The accuracy of the potentials can be checked by comparing the frequency response of DNVMs calculated using this or that interatomic potential with that calculated using the more accurate ab initio approach.DNVMs can also be used to train new,more accurate machine learning potentials for bcc metals.To address the above issues,it is important to analyze the properties of DNVMs,which is the main goal of this work.Considering only the point symmetry groups of the bcc lattice,34 DNVMs are found.Since interatomic potentials are not used in finding DNVMs,they are exact solutions for any type of potential.Here,the simplest interatomic potentials with cubic anharmonicity are used to simplify the analysis and to obtain some analytical results.For example,the dispersion relations for small-amplitude phonon modes are derived,taking into account interactions between up to the fourth nearest neighbor.The frequency response of the DNVMs is calculated numerically,and for some DNVMs examples of analytical analysis are given.The energy stored by the interatomic bonds of different lengths is calculated,which is important for testing interatomic potentials.The pros and cons of using DNVMs to test and improve interatomic potentials for metals are discussed.Since DNVMs are the natural vibrational modes of bcc crystals,any reliable interatomic potential must reproduce their properties with reasonable accuracy. 展开更多
关键词 Interatomic potentials molecular dynamics bcc lattice long-range interactions dispersion relation nonlinear dynamics exact solution delocalized nonlinear vibrational mode
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Event-related potentials reveal hypnotherapy's impact on attention bias in social anxiety disorder
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作者 Han Zhang Mi Zhang +8 位作者 Ni Li Wen-Zhuo Wei Lin-Xi Yang Yong-Yi Li Zhen-Yue Zu Li-Jun Ma Hui-Xue Wang Kai Wang Xiao-Ming Li 《World Journal of Psychiatry》 2025年第5期241-256,共16页
BACKGROUND Exploring hypnotherapy's potential to modulate attention bias offers promising avenues for treating social anxiety disorder(SAD).AIM To determine if hypnotherapy can alleviate social anxiety by influenc... BACKGROUND Exploring hypnotherapy's potential to modulate attention bias offers promising avenues for treating social anxiety disorder(SAD).AIM To determine if hypnotherapy can alleviate social anxiety by influencing attention bias,specifically identifying the aspects of attention processes affected by hypnosis.METHODS In this study,69 SAD participants were divided into three groups based on their Liebowitz Social Anxiety Scale scores:Experimental group,control group,and baseline group.The experimental group(n=23)underwent six weekly hypnosis sessions,while the control(n=23)and baseline groups(n=23)received no treatment.To evaluate alterations in SAD severity and attention bias towards threatening stimuli following hypnotherapy,we employed a combination of self-report questionnaires,an odd-one-out task,and electroencephalography recordings.RESULTS The experimental group showed significant reductions in P1,N170,N2pc,and late positive potential(LPP)brain wave activities during attention sensitivity and disengagement conditions.This indicates that hypnotherapy modulates early-stage face processing and later-stage emotional evaluation of threat-related stimuli in SAD patients.CONCLUSION Our findings highlight P1,N170,N2pc,and LPP as key neural markers in SAD treatment.By identifying these neural markers influenced by hypnotherapy,we offer insight into the mechanisms by which this treatment modality impacts attentional processes,potentially easing SAD symptoms. 展开更多
关键词 Social anxiety disorder Attention bias HYPNOTHERAPY Event-related potentials Face processing
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Numerical solution of the Dirac equation with scalar,vector,and tensor potentials
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作者 Alexander Wallén Kiessling Daniel Karlsson +2 位作者 Yuxin Zhao Mário Bettencourt Amaro Chong Qi 《Nuclear Science and Techniques》 2025年第12期244-250,共7页
Solving the Dirac equation has played an important role in many areas of fundamental physics.In this work,we present the Dirac equation solver DiracSVT,which solves the Dirac equation with scalar,vector,and tensor nuc... Solving the Dirac equation has played an important role in many areas of fundamental physics.In this work,we present the Dirac equation solver DiracSVT,which solves the Dirac equation with scalar,vector,and tensor nuclear potentials in spherical coordinate space.The shooting method was used with a Runge–Kutta 4 integration scheme.The potentials are parameterized in a Woods–Saxon form,which reproduce well the known single-particle states around all doubly magic nuclei and can be applied to study the shell evolution of exotic nuclei.The code can be easily extended to the study of other systems,including atomic,hadron,and molecular physics. 展开更多
关键词 Dirac equation Nuclear physics SCALAR Vector and tensor potentials Shell evolution
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Modeling stopping power of ions in plasmas using parametric potentials
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作者 Tanguy Barges Delattre Sébastien Rassou Jean-Christophe Pain 《Matter and Radiation at Extremes》 2025年第6期86-100,共15页
We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The... We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The free-electron contribution is described by the Maynard–Deutsch–Zimmerman formula,and the bound-electron contribution relies on the Bethe formula with corrections,in particular taking into account density and shell effects.The results of the bound-state computation using three different parametric potentials are investigated within the Garbet formalism for the mean excitation energy.The first parametric potential is due to Green,Sellin,and Zachor,the second one was proposed by Yunta,and the third one was introduced by Klapisch in the framework of atomic-structure computations.The results are compared with those of self-consistent average-atom calculations.This approach correctly bridges the limits of neutral and fully ionized matter. 展开更多
关键词 warm dense plasmaour free bound electrons maynard deutsch zimmerman formulaand parametric potentials ion stopping power bethe formula free electrons bound electrons
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REANN 2.0:An Efficient Package of Neural Network Potentials for Multi-Element Systems
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作者 Yixi Zhang Junfan Xia +1 位作者 Yaolong Zhang Bin Jiang 《Chinese Journal of Chemical Physics》 2025年第6期797-806,I0238,共11页
Recursively embedded atom neural network(REANN)is a general-purpose atomistic machine learning software package for representing potential energy and other physical properties.The original REANN 1.0 architecture is a ... Recursively embedded atom neural network(REANN)is a general-purpose atomistic machine learning software package for representing potential energy and other physical properties.The original REANN 1.0 architecture is a physically inspired invariant message passing neural network,which was designed for systems with a limited number of elements.It is efficient but hardly transferable to more complex multi-element systems.In this work,we release REANN 2.0 aimed at multi-element systems and universal potentials,which integrates element embedding and equivariant representation.Compared to the first version,REANN 2.0 demonstrates enhanced ele-ment transferability and higher accuracy across various periodic systems with higher efficiency.Built upon this framework,a pre-trained REANN-MPtrj model without fine-tuning accurately predicts the lithium-ion diffusion dynamics in a benchmark solid-state electrolyte Li_(3)YCl_(6).We hope this open-source software package will facilitate the development of computationally efficient universal potentials in the future. 展开更多
关键词 Machine learning potential Message passing neural network Universal machine learning potential Molecular dynamics
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A comprehensive review of meal replacement from dining table to sickbed:beyond biomedical potentials
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作者 Hao Qiang Tianshu Xu +4 位作者 Peng Ma Siyuan Zhang Guanhua Du Guifen Qiang Tengfei Ji 《Food Science and Human Wellness》 2025年第3期822-834,共13页
The emergence of meal replacement(MR)originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss.Indeed,the main application of current meal replacem... The emergence of meal replacement(MR)originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss.Indeed,the main application of current meal replacement is to lose body weight,whether patients with obesity,diabetes,fatty liver,infertile or pregnant women can benefit from weight loss.In addition,MRs still exhibit more biomedical potential in preventing and treating diseases,like anti-diabetes,improving fatty liver and kidney disease,preventing cancer,conceiving and reducing pregnancy complications,and improving life quality.Indeed,there are also disadvantages to meal replacement,including causing adverse effects,although most are acceptable and tolerated.To date,various commercially-developed MRs are walking from dining table to sickbed.Therefore,a scientific understanding of the advantages and disadvantages of meal replacements is crucial for their extensive application beyond biomedical potentials. 展开更多
关键词 Meal replacement Weight loss Biomedical potentials
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Three-component soliton states in spinor F=1 Bose-Einstein condensates with PT-symmetric generalized Scarf-Ⅱpotentials
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作者 Zhang-Lei Han Jun-Yi Lao +1 位作者 Jia-Rui Zhang Yu-Jia Shen 《Communications in Theoretical Physics》 2025年第4期1-11,共11页
Introducing PT-symmetric generalized Scarf-Ⅱpotentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seek stable soliton states in quasi-onedimensional spin-1 Bose-Einstein condensat... Introducing PT-symmetric generalized Scarf-Ⅱpotentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seek stable soliton states in quasi-onedimensional spin-1 Bose-Einstein condensates.In scenarios where the spin-independent parameter c_(0)and the spin-dependent parameter c_(2)vary,we use both analytical and numerical methods to investigate the three-coupled nonlinear Gross-Pitaevskii equations with PT-symmetric generalized Scarf-Ⅱpotentials.We obtain analytical soliton states and find that simply modulating c_(2)may change the analytical soliton states from unstable to stable.Additionally,we obtain numerically stable double-hump soliton states propagating in the form of periodic oscillations,exhibiting distinct behavior in energy exchange.For further investigation,we discuss the interaction of numerical double-hump solitons with Gaussian solitons and observe the transfer of energy among the three components.These findings may contribute to a deeper understanding of solitons in Bose-Einstein condensates with PT-symmetric potentials and may hold significance for both theoretical understanding and experimental design in related physics experiments. 展开更多
关键词 three-component soliton states PT-symmetric generalized Scarf-Ⅱpotentials Bose-Einstein condensates Three-coupled nonlinear Gross-Pitaevskii equations
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Bridging theory and practice:scalable prediction of alloy nanoparticle morphology and stability via machine-learned moment tensor potentials
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作者 Hung Ngo Manh Chi Ho Lee Sang Uck Lee 《Rare Metals》 2025年第11期9021-9035,共15页
Alloy nanoparticles exhibit unique properties that significantly differentiate them from their bulk counterparts,making them crucial for catalytic applications.However,the design of functional nanoparticles is often c... Alloy nanoparticles exhibit unique properties that significantly differentiate them from their bulk counterparts,making them crucial for catalytic applications.However,the design of functional nanoparticles is often constrained by the challenge of accurately predicting their stability,especially at large scales,where traditional ab initio methods are limited by computational demands.To overcome this,we introduce a novel method for predicting the thermodynamic stability and chemical ordering of alloy nanoparticles,utilizing the machine-learned moment tensor potential(MTP) integrated with active learning techniques.This approach allows precise assessment of the energetics of alloy nanoparticles regardless of morphology and remains scalable to experimental sizes,maintaining an optimal balance between computational efficiency and accuracy.The effectiveness of our method was demonstrated through its ability to predict the groundstate configurations of alloy spherical nanoparticles(SNPs),which is consistent with experimental results.In particular,the machine-learned MTP model enables a thorough investigation of the thermodynamic stability of SNPs and accurate prediction of the chemical ordering of SNPs depending on the type and composition ratio of the binary alloy systems.Consequently,this work not only highlights the superior performance of our approach over traditional computational methods for modeling large nanoparticles but also establishes a systematic approach for evaluating the stability of nanoparticles at full scale.We believe that our findings will pave the way for more reliable and scalable predictions in nanoparticle research and potentially accelerate the development of novel nanoparticle-based technologies. 展开更多
关键词 Machine learning potential ALLOY Nanoparticles stability Chemical ordering
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An in-depth study of spin-and momentum-dependent interaction potentials between two spin-1/2 fermions mediated by light spin-0 particles
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作者 Yang Zhong Zhi-Hui Guo Hai-Qing Zhou 《Communications in Theoretical Physics》 2025年第8期82-93,共12页
We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles,in both momentum and co... We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles,in both momentum and coordinate spaces.Our calculation is based on the four-point Green's function rather than the scattering amplitude.Among the sixteen potential components,eight that vanish in the non-relativistic limit are shown to acquire nonzero relativistic and off-shell corrections.In addition to providing relativistic and off-shell corrections to the operator basis commonly used in the literature,we introduce an alternative operator basis that facilitates the derivation of interaction potentials in the coordinate space.Furthermore,we calculate both the long-range and short-range components of the potentials,which can be useful for future experimental analyses at both macroscopic and atomic scales. 展开更多
关键词 AXION potential relativistic correction
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Effective nucleus-nucleus potentials for heavy-ion fusion reactions
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作者 Ning Wang Jin-Ming Chen Min Liu 《Nuclear Science and Techniques》 2025年第2期103-111,共9页
Based on the Skyrme energy density functional and reaction Q-value,this study proposed an effective nucleus-nucleus poten-tial for describing the capture barrier in heavy-ion fusion processes.The 443 extracted barrier... Based on the Skyrme energy density functional and reaction Q-value,this study proposed an effective nucleus-nucleus poten-tial for describing the capture barrier in heavy-ion fusion processes.The 443 extracted barrier heights were well reproduced with a root-mean-square(RMS)error of 1.53 MeV,and the RMS deviations with respect to 144 time-dependent Hartree-Fock capture barrier heights were only 1.05 MeV.Coupled with the Siwek-Wilczyński formula,wherein three parameters were determined by the proposed effective potentials,the measured capture cross sections at energies around the barriers were reasonably well reproduced for several fusion reactions induced by nearly spherical nuclei as well as by nuclei with large deformations,such as^(154)Sm and^(238)U.The shallow capture pockets and small values of the average barrier radii resulted in the reduction of the capture cross sections for 52,54Cr-and 64 Ni-induced reactions,which were related to the synthesis of new super-heavy nuclei. 展开更多
关键词 Nucleus-nucleus potential Fusion reactions Superheavy nuclei Capture cross sections
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Unchanged top surface-state structures in three-dimensional topological insulator Sb_(2)Te_(3) thin films in the presence of bottom-surface moiré potentials
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作者 Dezhi Song Fuyang Huang +1 位作者 Jun Zhang Ye-Ping Jiang 《Chinese Physics B》 2025年第12期400-404,共5页
The exertion of a long-period potential on two-dimensional(2D)systems leads to band-structure downfolding and the formation of mini flat bands,thereby providing a route for band engineering and enabling the realizatio... The exertion of a long-period potential on two-dimensional(2D)systems leads to band-structure downfolding and the formation of mini flat bands,thereby providing a route for band engineering and enabling the realization of new physical phenomena through the tuning of electron–electron interactions.In this work,the effect of the moiré superlattice formed between the substrate and the bottom quintuple layer(QL)of 3-and 4-QL three-dimensional(3D)topological insulator Sb_(2)Te_(3) thin films on the top surface states is investigated.The scanning tunneling spectra reveal that the bulk-like bands exhibit potential variations consistent with the moirépattern.In contrast,the surface states display only minimal potential variations,resulting in the absence of mini-band formation in the top surface states.These surface states remain nearly unaffected,as confirmed by Landau-level spectroscopy and simulations.The results suggest distinct roles of the bottom-surface moirépotential on the bulk states and the top surface states in the weak coupling regime between the two surfaces. 展开更多
关键词 scanning tunneling spectroscopy topological surface states HETEROSTRUCTURE moirépotential
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全球煤岩气资源潜力与分布 被引量:1
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作者 李国欣 陈瑞银 +7 位作者 温志新 张君峰 贺正军 冯佳睿 康海亮 孟庆洋 马超 苏玲 《石油勘探与开发》 北大核心 2026年第1期14-26,共13页
基于全球94个主要含煤盆地的区域地质、地震、钻井、测井、录井和生产动态等资料,在煤资源筛选和统计的基础上,参考国内煤岩气界定方法和评价标准,类比中国沉积盆地煤岩的构造沉积和埋藏热演化条件,以体积法为主,部分地区采用容积法,估... 基于全球94个主要含煤盆地的区域地质、地震、钻井、测井、录井和生产动态等资料,在煤资源筛选和统计的基础上,参考国内煤岩气界定方法和评价标准,类比中国沉积盆地煤岩的构造沉积和埋藏热演化条件,以体积法为主,部分地区采用容积法,估算全球煤岩气资源潜力,明确资源分布;基于5类共14项参数指标体系及赋分标准,对盆地排队优选,指出未来重点攻关方向。研究表明:(1)全球煤岩主要发育在4类原型盆地的4类沼泽环境,分布于五大成煤期和八大聚煤带,煤地质资源量约为42×10^(12) t,其中1 500 m以深煤岩的地质资源量为22×10^(12) t。(2)全球深层煤岩中赋存的煤岩气地质资源量约为232×10^(12) m^(3),其中俄罗斯、加拿大、美国、中国和澳大利亚5个国家煤岩气地质资源量之和占比超过90%,中国占比为24%。(3)全球煤岩气资源量前10大盆地为阿尔伯塔、库兹涅茨克、鄂尔多斯、东西伯利亚、博文、西西伯利亚、四川、南图尔盖、勒拿—维柳伊、塔里木,占比75%;二叠系、白垩系、石炭系、侏罗系、古近系—新近系的煤岩气资源量占比分别为32%,30%,18%,10%,7%。(4)综合评价全球煤岩气勘探开发最为现实的前10大重点盆地为阿尔伯塔、鄂尔多斯、库兹涅茨克、圣胡安、四川、东西伯利亚、落基山、博文、准噶尔、沁水。在中国成功开发实践的推动下,煤岩气目前正处于理论突破、技术创新和产量增长期,或将引领新一轮全球非常规油气革命。 展开更多
关键词 煤岩气 地质资源量 资源潜力 盆地类型 资源分布 含气量
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基于四重表征认知模型深度理解活化能概念——过氧化氢与碘化钾反应活化能测定的数字化实验
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作者 陈航 杜钦之 +2 位作者 葛琳 张明晓 陈时洪 《化学教育(中英文)》 北大核心 2026年第3期107-114,共8页
基于自主研发的数字化实验系统,开发了H_(2)O_(2)与KI反应活化能的测定实验。通过加热棒自动升温并结合温度传感器精准控温,利用电势传感器表征反应过程中电势随时间的变化,依据电势时间曲线所呈现的电势突跃确定反应时间,从而实现活化... 基于自主研发的数字化实验系统,开发了H_(2)O_(2)与KI反应活化能的测定实验。通过加热棒自动升温并结合温度传感器精准控温,利用电势传感器表征反应过程中电势随时间的变化,依据电势时间曲线所呈现的电势突跃确定反应时间,从而实现活化能的准确测定。同时,优化了H_(2)O_(2)与KI的物质的量之比、Na_(2)S_(2)O_(3)的用量、溶液酸度及反应温度。该数字化实验有效解决了传统活化能测定实验中“控温不稳”“计时不准”及“终点判定主观性强”的瓶颈,使得抽象的活化能形象化和定量化,利于化学反应基本原理教学质量的提升和学生学科素养的发展。 展开更多
关键词 活化能 数字化实验 温度传感器 电势传感器 电势突跃
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基于大数据分析的油井压裂潜力评价方法
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作者 王治国 刘健康 +5 位作者 姜雪岩 杨冰冰 王元庆 郑宪宝 梁鸿雁 穆文志 《大庆石油地质与开发》 北大核心 2026年第1期93-101,共9页
特高含水后期剩余油高度分散,油井压裂潜力精准评价难度加大。基于两相达西渗流理论,系统梳理影响压裂效果的6大方面29项因素,建立大庆XB开发区压裂样本库,采用相关分析和专家经验相结合确定压裂效果10项主控因素。在Kmeans聚类数据降... 特高含水后期剩余油高度分散,油井压裂潜力精准评价难度加大。基于两相达西渗流理论,系统梳理影响压裂效果的6大方面29项因素,建立大庆XB开发区压裂样本库,采用相关分析和专家经验相结合确定压裂效果10项主控因素。在Kmeans聚类数据降噪基础上,建立了基于LightGBM机器学习算法的压裂初期日增油量预测模型,并将预测模型与穷举搜索算法相结合,实现了以增油最佳或效益最佳为目标的压裂潜力快速评价。现场试验32口井,单井增油量较常规方法提高0.4 t/d,含水率较常规方法多下降1.7百分点,产出投入比达到4.1。该方法大幅度提高了压裂潜力评价精度及效率,为精准措施挖潜提供有效手段。 展开更多
关键词 油井压裂 机器学习 大数据 降噪 潜力评价
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基于知识势的领导过程研究
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作者 陈国权 罗庆烨 +2 位作者 王婧懿 林燕玲 王小晔 《中国管理科学》 北大核心 2026年第1期128-141,共14页
领导者和追随者之间的知识关系将如何影响领导过程?为了回答这个问题,本研究以势科学为基础,关注领导者-追随者二元关系的知识构成属性,提出了“知识势”的概念,将领导者相对追随者的知识势定义为领导者和追随者之间某一些领域的知识差... 领导者和追随者之间的知识关系将如何影响领导过程?为了回答这个问题,本研究以势科学为基础,关注领导者-追随者二元关系的知识构成属性,提出了“知识势”的概念,将领导者相对追随者的知识势定义为领导者和追随者之间某一些领域的知识差别与另一些领域的知识联系的乘积,认为领导者和追随者在某一些领域的知识差别越大,而在另一些领域的知识联系越紧密时,知识势就越大,越有助于领导过程的顺利开展。本研究通过理论研究得出:(1)领导者和追随者在某一些领域的知识差别有助于领导者建立说服过程中的可信度、指出追随者在工作中出现的问题并提供反馈与指导、培养追随者使其提升工作能力和职业素养;(2)领导者和追随者在某一些领域的知识联系有助于双方降低沟通和协调的成本并且构建更高质量的领导-成员交换关系;(3)基于“差别×联系=势”的思想,领导者和追随者在不同领域的知识差别和知识联系相互促进、相互补充,协同影响领导过程;(4)究竟是哪些领域的知识差别,又是哪些领域的知识联系构成了知识势,取决于情境因素。最后,本研究探讨了知识势对于领导力、团队知识构成以及势科学文献的理论贡献,以及它对组织和领导者提供的实践启示。 展开更多
关键词 知识势 势科学 领导力 领导-成员关系 团队知识构成
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低空经济产业关键核心技术发展潜力预测及竞争态势研究 被引量:1
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作者 杨东 彭前朝 魏泽龙 《统计与信息论坛》 北大核心 2026年第1期49-60,共12页
预测关键核心技术发展趋势,评估技术竞争态势,对低空经济产业实现技术突破和应用场景开发至关重要。首先,考虑知识流动的方向性和共现关系的权重性构建有向加权国际专利分类号共现网络,从地位垄断性、知识主导性和技术新颖性三个维度构... 预测关键核心技术发展趋势,评估技术竞争态势,对低空经济产业实现技术突破和应用场景开发至关重要。首先,考虑知识流动的方向性和共现关系的权重性构建有向加权国际专利分类号共现网络,从地位垄断性、知识主导性和技术新颖性三个维度构建指标体系识别低空经济产业关键核心技术;其次,结合技术生命周期理论预测关键核心技术发展潜力;最后,构建主体合作网络,通过专利持有与合作贡献两维度评估区域竞争力。围绕低空经济产业展开实证研究,预测并识别具备发展潜力的关键核心技术,涵盖B64U20/87(飞行器成像设备安装技术)、B64U60/40(可折叠起落架)、G06F17/10(电数字数据处理中的复杂数学运算方法)、H04W24/02(无线通信网络性能优化技术)、B64U10/14(四轴飞行器)和G06V20/17(飞行器拍摄装置或优化方法)。北京在上述技术领域综合实力位居全国第一,广东、江苏、浙江和陕西处于第二梯队。基于研究结论,提出以下政策建议:一是强化技术预见能力,建立低空经济专利大数据监测平台,定期开展技术扫描与竞争态势分析;二是完善产业链生态,推动数据处理、飞控系统、通信导航等重点技术领域协同发展;三是建立区域协同创新机制,形成以北京为引领、多省份协同分工的集群发展格局;四是推动差异化产品开发,依托地方优势打造低空物流、旅游等特色应用场景,避免同质竞争。研究结论为政府和企业把握低空经济产业技术发展路径、认识技术发展差距、制定发展战略提供了参考依据。 展开更多
关键词 低空经济产业 关键核心技术 发展潜力预测 竞争态势分析 区域竞争力
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