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Dynamic graph exploration by interactively linked node-link diagrams and matrix visualizations 被引量:1
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作者 Michael Burch Kiet Bennema ten Brinke +3 位作者 Adrien Castella Ghassen Karray Sebastiaan Peters Vasil Shteriyanov Rinse Vlasvinkel 《Visual Computing for Industry,Biomedicine,and Art》 EI 2021年第1期219-232,共14页
The visualization of dynamic graphs is a challenging task owing to the various properties of the underlying relational data and the additional time-varying property.For sparse and small graphs,the most efficient appro... The visualization of dynamic graphs is a challenging task owing to the various properties of the underlying relational data and the additional time-varying property.For sparse and small graphs,the most efficient approach to such visualization is node-link diagrams,whereas for dense graphs with attached data,adjacency matrices might be the better choice.Because graphs can contain both properties,being globally sparse and locally dense,a combination of several visual metaphors as well as static and dynamic visualizations is beneficial.In this paper,a visually and algorithmically scalable approach that provides views and perspectives on graphs as interactively linked node-link and adjacency matrix visualizations is described.As the novelty of this technique,insights such as clusters or anomalies from one or several combined views can be used to influence the layout or reordering of the other views.Moreover,the importance of nodes and node groups can be detected,computed,and visualized by considering several layout and reordering properties in combination as well as different edge properties for the same set of nodes.As an additional feature set,an automatic identification of groups,clusters,and outliers is provided over time,and based on the visual outcome of the node-link and matrix visualizations,the repertoire of the supported layout and matrix reordering techniques is extended,and more interaction techniques are provided when considering the dynamics of the graph data.Finally,a small user experiment was conducted to investigate the usability of the proposed approach.The usefulness of the proposed tool is illustrated by applying it to a graph dataset,such as e co-authorships,co-citations,and a Comprehensible Perl Archive Network distribution. 展开更多
关键词 Dynamic graph visualization node-link diagrams Adjacency matrices LAYOUTS Reorderings
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Visualizing ordered bivariate data on node-link diagrams 被引量:1
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作者 Osman Akbulut Lucy McLaughlin +2 位作者 Tong Xin Matthew Forshaw Nicolas S.Holliman 《Visual Informatics》 EI 2023年第3期22-36,共15页
Node-link visual representation is a widely used tool that allows decision-makers to see details about a network through the appropriate choice of visual metaphor.However,existing visualization methods are not always ... Node-link visual representation is a widely used tool that allows decision-makers to see details about a network through the appropriate choice of visual metaphor.However,existing visualization methods are not always effective and efficient in representing bivariate graph-based data.This study proposes a novel node-link visual model–visual entropy(Vizent)graph–to effectively represent both primary and secondary values,such as uncertainty,on the edges simultaneously.We performed two user studies to demonstrate the efficiency and effectiveness of our approach in the context of static nodelink diagrams.In the first experiment,we evaluated the performance of the Vizent design to determine if it performed equally well or better than existing alternatives in terms of response time and accuracy.Three static visual encodings that use two visual cues were selected from the literature for comparison:Width-Lightness,Saturation-Transparency,and Numerical values.We compared the Vizent design to the selected visual encodings on various graphs ranging in complexity from 5 to 25 edges for three different tasks.The participants achieved higher accuracy of their responses using Vizent and Numerical values;however,both Width-Lightness and Saturation-Transparency did not show equal performance for all tasks.Our results suggest that increasing graph size has no impact on Vizent in terms of response time and accuracy.The performance of the Vizent graph was then compared to the Numerical values visualization.The Wilcoxon signed-rank test revealed that mean response time in seconds was significantly less when the Vizent graphs were presented,while no significant difference in accuracy was found.The results from the experiments are encouraging and we believe justify using the Vizent graph as a good alternative to traditional methods for representing bivariate data in the context of node-link diagrams. 展开更多
关键词 Bivariate network visualization Edge visualization Uncertainty visualization node-link diagram Quantitative evaluation
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SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)Diagram as a Petrochemical Tool for Deciphering the Tectono-Magmatic Characterization of Granitoid Suites 被引量:1
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作者 SUN Mingming WANG Yang 《Acta Geologica Sinica(English Edition)》 2025年第2期598-610,共13页
The SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)diagram is an empirically derived major element-based equivalent to the modal IUGS alkali feldspar-quartz-plagioclase classification scheme for granitoids.It employs the cont... The SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)diagram is an empirically derived major element-based equivalent to the modal IUGS alkali feldspar-quartz-plagioclase classification scheme for granitoids.It employs the content of SiO_(2)and CaO/(CaO+K_(2)O)ratio to approximate the IUGS classification diagram and a normative-based Q'-ANOR plot.Four trends have been superimposed onto the SiO_(2)'-CaO/(CaO+K_(2)O)diagram based on published datasets from the Peninsular Ranges(calcic:C),Tuolumne(calc-alkalic:CA),Sherman(alkali-calcic:AC),and Bjerkreim-Sokndal(alkalic:A)batholiths,which were employed to constrain the positions of the C-CA,CA-AC and AC-A suite boundaries on the SiO_(2)versus(Na_(2)O+K_(2)O-CaO)(or modified alkali-lime index,MALI)granitic classification diagram.A merit of the SiO_(2)'-CaO/(CaO+K_(2)O)plot is identifying rock types comprising a suite and their relative abundances.The distinguished projections of five typical granitoid assemblages,which are summarized by Bonin et al.(2020),demonstrate the ability of SiO_(2)'-CaO/(CaO+K_(2)O)diagram to decipher their petrogenesis.The SiO_(2)'-CaO/(CaO+K_(2)O)plots for the plutonic suites of'known'tectonic settings can reveal their evolution paths and the lithological statistics.Accordingly,it is suggested that the SiO_(2)'-CaO/(CaO+K_(2)O)plot can distinguish the tectonic environments of plutonic suits by comparing the plutonic suites or batholiths of'unknown'tectonic context to the published datasets from granitoid suites formed within'known'tectonic settings.The modified SiO_(2)'-CaO/(CaO+K_(2)O)diagram links the bulk chemical composition of granitoid suites to the likely source,magmatic evolution,and tectonic setting;thus,it may be a useful tectono-magmatic classification scheme for granitoid suites. 展开更多
关键词 classification of granitoid major-element chemistry SiO_(2)'–CaO/(CaO+K_(2)O)diagram tectono-magmatic character
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Growth diagram of AlN epilayers grown by plasma-assisted molecular beam epitaxy
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作者 Huan Liu Pengfei Shao +8 位作者 Yu Liu Qi Yao Tao Tao Zili Xie Dunjun Chen Bin Liu Hai Lu Rong Zhang Ke Wang 《Chinese Physics B》 2025年第7期580-585,共6页
We have investigated homoepitaxy of Al N films grown by molecular beam epitaxy(MBE)on Al N/sapphire templates.The MBE epitaxy of Al N at the low temperature range,which is suitable for Al Ga N,encounters significant c... We have investigated homoepitaxy of Al N films grown by molecular beam epitaxy(MBE)on Al N/sapphire templates.The MBE epitaxy of Al N at the low temperature range,which is suitable for Al Ga N,encounters significant challenge in preventing Al droplet and pits,since the migration and desorption rate of Al atom are very low.In contrast,by elevating the growth temperature,such a difficulty can be effectively overcome,and we were able to grow Al N films with much improved surface morphology and obtained step flow growth mode without any Al droplets and pits.The cathodoluminescence spectroscopy indicate that the impurity incorporation and defect generation in the Al N epilayers was suppressed by elevating the growth temperature.A systematic investigation on the influence of Al beam flux and growth temperature in a very wide range on the Al N films has been conducted,and a comprehensive growth diagram of MBE Al N has been obtained. 展开更多
关键词 ALN EPITAXY films morphology growth diagram
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Introducing a new geostatistical approach to classify groundwater samples based on Stiff diagram: Case study of Chahardoly aquifer, west of Iran
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作者 Sajjad Moradi Nazarpoor Mohsen Rezaei +2 位作者 Hadi Jafari Yazdan Mohebi Reza Mirbageri 《Journal of Groundwater Science and Engineering》 2025年第4期423-433,共11页
Groundwater quality is pivotal for sustainable resource management,necessitating comprehen-sive investigation to safeguard this critical resource.This study introduces a novel methodology that inte-grates stiff diagra... Groundwater quality is pivotal for sustainable resource management,necessitating comprehen-sive investigation to safeguard this critical resource.This study introduces a novel methodology that inte-grates stiff diagrams,geostatistical analysis,and geometric computation to delineate the extent of a confined aquifer within the Chahrdoly aquifer,located west of Hamadan,Iran.For the first time,this approach combines these tools to map the boundaries of a confined aquifer based on hydrochemical characteristics.Stiff diagrams were used to calculate geometric parameters from groundwater chemistry data,followed by simulation using a linear model incorporating the semivariogram parameterγ(h).The Root Mean Square Error(RMSE)of the linear model was used to differentiate confined from unconfined aquifers based on hydrochemical signatures.Validation was conducted by generating a cross-sectional hydrogeological layer from well logs,confirming the presence of aquitard layers.The results successufully delineated the confined aquifer's extent,showing strong agreement with hydrogeological log data.By integrating stiff diagrams with semivariogram analysis,this study enhances the understanding of hydrochemical processes,offering a robust framework for groundwater resource identification and management. 展开更多
关键词 GEOSTATISTICS Stiff diagram SEMIVARIOGRAM Confined aquifer Chahardoly Asadabad
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Development and validation of a nomogram model for predicting the risk of H-type hypertension with pulse diagram parameters
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作者 Siman WANG Mengchu ZHANG +4 位作者 Minghui YAO Tianxiao XIE Rui GUO Yiqin WANG Haixia YAN 《Digital Chinese Medicine》 2025年第2期174-182,共9页
Objective To develop an onset risk prediction nomogram for patients with homocysteine-type(H-type)hypertension(HTH)based on pulse diagram parameters to assist early clinical prediction and diagnosis of HTH.Methods Pat... Objective To develop an onset risk prediction nomogram for patients with homocysteine-type(H-type)hypertension(HTH)based on pulse diagram parameters to assist early clinical prediction and diagnosis of HTH.Methods Patients diagnosed with essential hypertension and admitted to Shanghai Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine,Shang-hai Hospital of Traditional Chinese Medicine,and Shanghai Hospital of Integrated Tradition-al Chinese and Western Medicine from July 6th 2020 to June 16th 2021,and from August 11th 2023 to January 22nd 2024,were enrolled in this retrospective research.The baselines and clinical biochemical indicators of patients were collected.The SMART-I TCM pulse instru-ment was applied to gather pulse diagram parameters.Multivariate logistic regression was adopted to analyze the risk factors for HTH.RStudio was employed to construct the nomo-gram model,receiver operating characteristic(ROC)curve,and calibration curve(bootstrap self-sampling 200 times),and clinical decision curve were drawn to evaluate the model’s dis-crimination and clinical effectiveness.Results A total of 168 hospitalized patients with essential hypertension were selected and di-vided into non-HTH group(n=29)and HTH group(n=139).Compared with non-HTH group,HTH group had a lower body mass index(BMI),and higher proportions of male pa-tients and drinkers(P<0.05).The ventricular wall thickening(VWT)could not be deter-mined.The proportions of left common carotid intima-media wall thickness(LCCIMWT)and serum creatinine(SCR)were higher in HTH group(P<0.05).The pulse diagram parameter As was significantly higher,and H4/H1 and T1/T were lower in HTH group(P<0.05).Gender,al-cohol consumption,serum creatinine,and the pulse diagram parameter H4/H1 were identi-fied as independent risk factors for HTH(P<0.05).The nomogram’s area under the ROC curve(AUC)was 0.795[95%confidence interval(CI):(0.7066,0.8828)],with a specificity of 0.724 and sensitivity of 0.799.After 200 times repeated bootstrap self-samplings,the calibra-tion curve showed that the simulated curve fits well with the actual curve(x^(2)=9.5002,P=0.3019).The clinical decision curve indicated that the nomogram’s applicability was optimal when the threshold for predicting HTH was between 0.38 and 1.00.Conclusion The nomogram model could be valuable for predicting the onset risk of HTH and pulse diagram parameters can facilitate early screening and prevention of HTH. 展开更多
关键词 H-type hypertension Homocysteine NOMOGRAM Pulse diagram parameters Prediction model
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Design of high-performance Cu-Be alloy based on machine learning with integrated phase diagram information
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作者 Wei Chen Yan-Bin Jiang +7 位作者 Fei Tan Zi-Xuan Zhao Mu-Zhi Ma Meng Wang Xiao-Yu Jiang Yi-Wei Qin Qian Lei Zhou Li 《Rare Metals》 2025年第8期5824-5843,共20页
High cost of raw materials and the insufficient research on alloy systems severely constrained the development of Cu-Be alloys.The complex coupling relationship between composition and preparation process poses challe... High cost of raw materials and the insufficient research on alloy systems severely constrained the development of Cu-Be alloys.The complex coupling relationship between composition and preparation process poses challenges to the use of machine learning methods for the precise design of Cu-Be alloy.This study develops a novel method for integrated design of copper alloy composition and processing based on a Long Short-Term Memory model followed by an Encoder model(LSTM-Encoder)and enriches the framework by integrating phase diagram information.This approach not only capitalizes on the patterns of microstructural evolution during heat treatment as indicated in phase diagrams to reveal their intrinsic links with alloy performance but also eliminates cross-interference within sample data,thus significantly enhancing the model's generalization and predictive accuracy,which achieves high efficient and precise design of low-cost(low Be content) and high-performance Cu-Be alloys.Compared with other models,the LSTM-Encoder model incorporating phase diagram information(LSTM-Encoder-Ⅱ) showed significant superiority in prediction accuracy.After two rounds of experimental verification and iteration,the LSTM-Encoder-Ⅱ model attained prediction accuracies of 96% for hardness and 93% for electrical conductivity.Various Cu-Be-X alloys with excellent comprehensive performance and low cost have been designed,and Cu-1.5Be-0.1Ni-0.3Co alloy achieves a tensile strength of 1211 MPa and an electrical conductivity of 30.3% IACS,and Cu-1.5Be-0.6Ni alloy attains a tensile strength of1290 MPa and an electrical conductivity of 29.3% IACS,both of which are comparable to the C17200 alloy,with raw material cost reduced by more than 14%. 展开更多
关键词 Phase diagram information Cu-Be alloys Machine learning Alloy design LSTM-Encoder
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Diagnostic Illustrations:Integration and Changes of Western Transmission of Traditional Chinese Medicine Pulse Diagnosis Diagrams
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作者 MA Jie 《Chinese Medicine and Culture》 2025年第2期111-123,共13页
Throughout the long development of the Silk Road,traditional medical techniques from various countries have continued to intersect and integrate,and traditional Chinese medicine(TCM)has also been transmitted to Eurasi... Throughout the long development of the Silk Road,traditional medical techniques from various countries have continued to intersect and integrate,and traditional Chinese medicine(TCM)has also been transmitted to Eurasia via the Silk Road.In the process of TCM knowledge dissemination,the tangible pulse diagnosis diagrams(脉诊图)have been collected in works such as Tānksūqnāmah(《伊利汗中国科技珍宝书》Ilkhanate Chinese Science and Technology Treasure Book),Specimen Medicinae Sinicae(《中医指南》A Guide to Traditional Chinese Medicine),and Die Chinesische Medizin(《中华医学》Chinese Medicine),and has become an important carrier and cultural symbol of pulse diagnostics,integrating into Eurasian medicine.The dissemination of TCM pulse diagnosis and the pulse diagnosis diagrams are closely related to Nan Jing(《难经》The Classic of Difficult Issues)and the pulse studies of the Jin dynasty medical scholar,Wang Shuhe(王叔和).The study found that the pulse diagnosis diagrams had distinct characteristics in its transmission to the West in different eras,and they are analyzed from the perspectives of“communicators(translators)”,“translation characteristics”,“cultural background”,“inheritance system”,revealing multiple integrations and transformations of ancient TCM pulse diagnosis diagrams in the East-West exchange and mutual learning.The pulse diagnosis diagrams have gradually become a symbol of TCM diagnostic methods,forming an inseparable link between TCM and pulse diagnosis in the minds of scholars and the public in the East and West. 展开更多
关键词 Pulse diagnosis diagrams TRANSLATION ACCULTURATION Medical exchange Traditional Chinese medicine
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AI-driven Automated Construction of Block Copolymer Phase Diagrams
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作者 Qing-Shu Dong Qing-Liang Song +1 位作者 Kun Tian Wei-Hua Li 《Chinese Journal of Polymer Science》 2025年第10期1730-1738,共9页
The self-assembly of block copolymers serves as an effective approach for fabricating various periodic ordered nanostructures. By employing self-consistent field theory (SCFT) to calculate the phase diagrams of block ... The self-assembly of block copolymers serves as an effective approach for fabricating various periodic ordered nanostructures. By employing self-consistent field theory (SCFT) to calculate the phase diagrams of block copolymers, one can accurately predict their self-assembly behaviors, thus providing guidance for the fabrication of various novel structures. However, SCFT is highly sensitive to initial conditions because it finds the free energy minima through an iterative process. Consequently, constructing phase diagrams using SCFT typically requires predefined candidate structures based on the experience of researchers. Such experience-dependent strategies often miss some structures and thus result in inaccurate phase diagrams. Recently, artificial intelligence (AI) techniques have demonstrated significant potential across diverse fields of science and technology. By leveraging AI methods, it is possible to reduce reliance on human experience, thereby constructing more robust and reliable phase diagrams. In this work, we demonstrate how to combine AI with SCFT to automatically search for self-assembled structures of block copolymers and construct phase diagrams. Our aim is to realize automatic construction of block copolymer phase diagrams while minimizing reliance on human prior knowledge. 展开更多
关键词 Block copolymer Self-consistent field theory Phase diagram Artificial intelligence Bayesian optimization
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Identification indexes and diagrams for natural gas origin:Connotation,significance and application
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作者 PENG Ping'an HOU Dujie +8 位作者 TENGER NI Yunyan GONG Deyu WU Xiaoqi FENG Ziqi HU Guoyi HUANG Shipeng YU Cong LIAO Fengrong 《Petroleum Exploration and Development》 2025年第3期573-586,共14页
Accurate identification of natural gas origin is fundamental to the theoretical research on natural gas geosciences and the exploration deployment and resource potential assessment of oil and gas.Since the 1970s,Acade... Accurate identification of natural gas origin is fundamental to the theoretical research on natural gas geosciences and the exploration deployment and resource potential assessment of oil and gas.Since the 1970s,Academician Dai Jinxing has developed a comprehensive system for natural gas origin determination,grounded in geochemical theory and practice,and based on the integrated analysis of stable isotopic compositions,molecular composition,light hydrocarbon fingerprints,and geological context.This paper systematically reviews the core framework established by him and his team according to related references and application results,focusing on the conceptual design and technical pathways of key diagnostic diagrams such asδ^(13)C_(1)-C_(1)/(C_(2)+C_(3)),δ^(13)C_(1)-δ^(13)C_(2)-δ^(13)C_(3),δ^(13)CCO_(2)versus CO_(2)content,and the C7light hydrocarbon ternary plot.We evaluate the applicability and innovation of these tools in distinguishing between oil-type gas,coal-derived gas,microbial gas,and abiogenic gas,as well as in identifying mixed-source gases and multi-stage charging systems.The findings suggest that this identification system has significantly advanced natural gas geochemical interpretation in China,shifting from single-indicator analyses to multi-parameter integration and from qualitative assessments to systematic graphical identification,and has also exerted considerable influence on international research in natural gas geochemistry.The structured overview of the development trajectory of natural gas origin discrimination methodologies provides a technical support for natural gas geological theory and practice and offers a scientific foundation for the academic evaluation and application of related achievements. 展开更多
关键词 natural gas natural gas geochemistry origin identification identification index identification diagram coal-derivedgas inorganic origin
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Virtual force node deployment algorithm of field observation instrument based on voronoi diagram
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作者 HUO Jiuyuan WANG Lei 《Journal of Measurement Science and Instrumentation》 2025年第3期435-445,共11页
Aiming at node deployment in the monitoring area of the field observation instrument network in the cold and arid regions,we propose a virtual force algorithm based on Voronoi diagram(VFAVD),which adopts probabilistic... Aiming at node deployment in the monitoring area of the field observation instrument network in the cold and arid regions,we propose a virtual force algorithm based on Voronoi diagram(VFAVD),which adopts probabilistic sensing model that is more in line with the actual situation.First,the Voronoi diagram is constructed in the monitoring area to determine the Thiessen polygon of each node.Then,the virtual force on each node is calculated,and the node update its position according to the direction and size of the total force,so as to achieve the purpose of improving the network coverage rate.The simulation results show that the proposed algorithm can effectively improve the coverage rate of the network,and also has a good effect on the coverage uniformity. 展开更多
关键词 field observation instrument network node deployment Voronoi diagram virtual force network coverage rate
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Theoretical prediction of KF-RbF-CsF-BeF_(2)system:phase diagrams calculation and ab initio molecular dynamics
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作者 Hui-Qin Yin Lin-Bing Jiang +3 位作者 Xuan-Chun Wu Biao Hu Yang Wang Wen-Guan Liu 《Nuclear Science and Techniques》 2025年第11期149-166,共18页
Thermodynamic optimization of the AF-BeF_(2)(A=K,Rb,and Cs),KF-CsF,and RbF-CsF systems was performed within the framework of phase diagrams calculation.The model parameters were optimized based on experimental data an... Thermodynamic optimization of the AF-BeF_(2)(A=K,Rb,and Cs),KF-CsF,and RbF-CsF systems was performed within the framework of phase diagrams calculation.The model parameters were optimized based on experimental data and theoretically calculated values.The results show that the thermodynamically calculated values for the AF-BeF_(2)(A=K,Rb,and Cs),KF-CsF,and RbF-CsF systems agree well with the experimental data.Next,a set of reliable and self-consistent thermodynamic databases was built,and the liquidus projections and invariant points of the sub-ternary systems of the KF-RbF-CsF-BeF_(2)system were calculated.Furthermore,the melting temperature with the corresponding composition was predicted using the phase diagrams calculation technique,and the radial distribution functions,coordination numbers,angular distribution functions,and diffusion coefficients of the quaternary KF-RbF-CsF-BeF_(2)system were calculated using ab initio molecular dynamics.The results show that the quaternary KF-RbF-CsF-BeF_(2)system with the proportion 3.50-28.92-21.78-45.80 mol%or 1.80-35.42-52.40-10.38 mol%is one of the most promising candidate coolants for molten salt reactors in terms of thermodynamics and kinetics.This work provides direct guidelines for the screening and optimization of molten salts in the nuclear energy field. 展开更多
关键词 Molten salt KF-RbF-CsF-BeF_(2) Calculation of phase diagrams Ab initio molecular dynamics
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Phase diagram as a lens for unveiling thermodynamics trends in lithium-sulfur batteries
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作者 Bo-Bo Zou Hong-Jie Peng 《Chinese Chemical Letters》 2025年第7期8-9,共2页
Lithium-sulfur battery(LSB)has attracted worldwide attention owing to its overwhelmingly high theoretical energy density of 2600Wh/kg due to the unique 16-electron electrochemical conversion reaction of elemental sulf... Lithium-sulfur battery(LSB)has attracted worldwide attention owing to its overwhelmingly high theoretical energy density of 2600Wh/kg due to the unique 16-electron electrochemical conversion reaction of elemental sulfur(S_(8))[1].However,the electrochemical conversion reaction of S_(8) is an exceedingly complex process that involves the generation of multiple intermediates(e.g.,lithium polysulfides(LiPSs))and multiphase transitions[1,2].Currently,the mechanistic investigations of the electrochemical conversion reaction of S_(8) upon discharging a LSB cell heavily rely on electrochemical titration and spectroscopic techniques[3].Nevertheless,the considerable complexity and intrinsic instability of the LSB system present substantial obstacles to obtaining accurate information for all sulfur-containing species,which significantly obstructs in-depth elucidation of the fundamental discharge mechanism of LSB[3,4]. 展开更多
关键词 generation multiple electrochemical conversion reaction electrochemical conversion THERMODYNAMICS mechanistic investigations phase diagram lithium sulfur batteries spectroscopic techniques
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煤炭超临界水气化-氧化解耦式制氢系统能效分析
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作者 王浩 孙维东 +1 位作者 王闯 吕友军 《西安交通大学学报》 北大核心 2026年第2期59-70,共12页
针对煤炭超临界水气化制氢系统整体能量集成优化不足的问题,提出了一种以1000 m^(3)·h^(-1)氢气产量(在0℃、1个大气压的标准条件下)为目标的煤炭超临界水气化-氧化解耦式超临界水制氢示范系统,并基于热力学方法对该系统进行了能... 针对煤炭超临界水气化制氢系统整体能量集成优化不足的问题,提出了一种以1000 m^(3)·h^(-1)氢气产量(在0℃、1个大气压的标准条件下)为目标的煤炭超临界水气化-氧化解耦式超临界水制氢示范系统,并基于热力学方法对该系统进行了能效分析。基于不同煤种的气化特性确定了解耦式系统的设计参数,考察了不同煤质、温度和压力对系统能量效率的影响规律;根据图像㶲分析方法揭示了气化器、氧化器、换热器组和系统整体不可逆损失的产生机理。结果表明:在水煤质量比为1∶4,质量流量为1280 kg·h^(-1)的条件下,红柳林煤的制氢效率高达66.92%;系统制氢效率随着预热水温度的增加呈现出先增加后下降的趋势,随着反应压力的增加,总产气量和氢气产量均下降;系统中气化反应器和氧化反应器的不可逆损失最大,高品位产气与低品位吸热混合工质之间存在较大品位差距是不可逆损失产生的主要原因;减少换热器不可逆损失的途径是减少冷热流体的品位差,即减少换热全过程的温度差。该研究结果可为煤炭超临界水气化制氢系统设计提供技术参考。 展开更多
关键词 超临界水气化 解耦式系统 图像㶲分析 热力学
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基于因果图的研究前沿演化动因识别研究
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作者 白如江 任前前 +3 位作者 陈鑫 牛湘荷 张新雨 刘睿琳 《现代情报》 北大核心 2026年第2期45-60,共16页
[目的/意义]在全球科技创新格局加速重构背景下,揭示研究前沿演化的动因有助于为中国科技战略的前瞻布局提供情报支持。[方法/过程]基于BERTopic主题模型融合前沿判别指标,识别研究前沿主题,并运用主题相似度测度方法解析其演化路径。... [目的/意义]在全球科技创新格局加速重构背景下,揭示研究前沿演化的动因有助于为中国科技战略的前瞻布局提供情报支持。[方法/过程]基于BERTopic主题模型融合前沿判别指标,识别研究前沿主题,并运用主题相似度测度方法解析其演化路径。创新性地提出大语言模型与因果图融合分析方法,构建面向文本的因果要素智能抽取与结构化语义表征模型。结合Louvain算法构建领域因果图,借助关键节点测度、因果流模式建模和因果子图发现等方法,从关键驱动要素、作用模式及演化趋势3个层面揭示研究前沿演化的动因及其特征。[结果/结论]研究发现,生物交叉领域研究前沿演化的动因包含SARS-CoV-2、Alzheimer’s Disease、ALKBH3等事件要素,因果流模式和因果子图实现了因果环节与因果路径轨迹的刻画,为研究前沿主题演化深层次逻辑揭示提供了证据支持。 展开更多
关键词 研究前沿 主题演化 动因识别 大语言模型 因果图
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基于高精度地质建模技术的断层侧向封闭性评价方法——以辽河坳陷兴隆台构造带太古界潜山油气藏为例
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作者 李滨 闵忠顺 +3 位作者 孟令娜 张源李 尹剑峰 周培杰 《岩性油气藏》 北大核心 2026年第1期126-135,共10页
Allan图分析对于断层封闭性的研究具有重要意义。以辽河坳陷兴隆台构造带太古界潜山油气藏为例,综合测录井、三维地震和实验分析测试资料,提出了一种基于高精度地质建模技术的改进Allan图法,用于分析断层封闭性。研究结果表明:(1)基于井... Allan图分析对于断层封闭性的研究具有重要意义。以辽河坳陷兴隆台构造带太古界潜山油气藏为例,综合测录井、三维地震和实验分析测试资料,提出了一种基于高精度地质建模技术的改进Allan图法,用于分析断层封闭性。研究结果表明:(1)基于井-震联合建立的高精地质模型可解决井位数据缺失的问题,在精细剖析变质岩潜山各个区域的岩性发育情况及造缝能力的基础上,高精地质模型可准确刻画断层两侧的地层接触关系和岩性分布规律,经人工检查和调整可形成最终的改进Allan图。(2)研究区断面上共存在6种岩性对接模式,其中具备良好封闭性的对接模式包含角砾岩-泥岩、混合岩-泥岩、混合岩-片麻岩、混合岩-角砾岩、角砾岩-角砾岩,区外围断层F3、F5全封闭,区内渗漏点海拔为-4 390 m。(3)结合模糊数学方法、现场流体分布进行了交叉检验,各个区域分析结果与改进Allan图法分析的断层侧向封闭性吻合度高,说明该方法在变质岩潜山表现出优异的适用性和准确性,具有较高的应用价值。 展开更多
关键词 改进Allan图法 断层封闭性 储气库 高精度地质建模 太古界潜山 兴隆台构造带 辽河坳陷
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基于谱聚类的随机子空间模态参数自动识别
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作者 胡志祥 程成 +1 位作者 胥河阳 黄磊 《工程力学》 北大核心 2026年第1期39-49,共11页
实现模态参数自动识别对于实时结构健康监测系统具有重要意义。针对随机子空间方法输出的稳定图存在大量虚假模态的不足,该文提出了基于加权距离函数的谱聚类算法,并将其应用于稳定图的自动识别,旨在提高模态识别的精确性。介绍了谱聚... 实现模态参数自动识别对于实时结构健康监测系统具有重要意义。针对随机子空间方法输出的稳定图存在大量虚假模态的不足,该文提出了基于加权距离函数的谱聚类算法,并将其应用于稳定图的自动识别,旨在提高模态识别的精确性。介绍了谱聚类算法和随机子空间方法的原理,并将加权距离函数用于计算待聚类节点的相似矩阵,综合考虑模态数据的贡献。通过模态验证准则对稳定图的模态参数进行预处理,剔除明显的虚假模态,以提高聚类效果。将该文方法应用于平面桁架模型和实测人行桥的模态参数计算,结果表明所提出的方法能有效剔除稳定图中的虚假模态,并具有良好的鲁棒性。 展开更多
关键词 结构健康监测 模态参数识别 随机子空间 谱聚类 稳定图 距离函数
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Predominance diagrams for Zn(Ⅱ)-NH_3-Cl^--H_2O system 被引量:3
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作者 丁治英 陈启元 +1 位作者 尹周澜 刘葵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期832-840,共9页
The thermodynamics in zinc hydrometallurgical process was studied using a chemical equilibrium modeling code(GEMS) to predict the zinc solubility and construct the species distribution and predominance diagrams for ... The thermodynamics in zinc hydrometallurgical process was studied using a chemical equilibrium modeling code(GEMS) to predict the zinc solubility and construct the species distribution and predominance diagrams for the Zn(Ⅱ)-NH3-H2O and Zn(Ⅱ)-NH3-Cl--H2O system.The zinc solubilities in ammoniacal solutions were also measured with equilibrium experiments,which agree well with the predicted values.The distribution and predominance diagrams show that ammine and hydroxyl ammine complexes are the main aqueous Zn species,Zn(NH3)24-is predominant in weak alkaline solution for both Zn(Ⅱ)-NH3-H2O and Zn(Ⅱ)-NH3-Cl--H2O systems.In Zn(Ⅱ)-NH3-Cl--H2O system,the ternary complexes containing ammonia and chloride increase the zinc solubility in neutral solution.There are three zinc compounds,Zn(OH)2,Zn(OH)1.6Cl0.4 and Zn(NH3)2Cl2,on which the zinc solubility depends,according to the total ammonia,chloride and zinc concentration.These thermodynamic diagrams show the effects of ammonia,chloride and zinc concentration on the zinc solubility,which can provide thermodynamic references for the zinc hydrometallurgy. 展开更多
关键词 THERMODYNAMICS predominance diagram zinc hydrometallurgy ammonia leaching
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φ-pH diagram of V-Ti-H_2O system during pressure acid leaching of converter slag containing vanadium and titanium 被引量:4
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作者 牟望重 张廷安 +2 位作者 豆志河 吕国志 刘燕 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2078-2086,共9页
To analyze the thermodynamic characteristics of leaching process of converter slag, φ-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures rangi... To analyze the thermodynamic characteristics of leaching process of converter slag, φ-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures ranging from 60 to 200 ℃ was obtained by recently published critically assessed standard Gibbs energies and activity coefficients of various species. When pH2, stable regions of V3+, VO2+ and VO2+ exist in the stable region of TiO2. The pH values of stable regions of vanadium and titanium decrease and redox potentials become more positive with the temperature increasing. Vanadium and titanium could be separated by one-step leaching based on thermodynamics. The experiment results of pressure acid leaching of converter slag show that leaching rates of vanadium and titanium are 96.87% and 8.76% respectively, at 140 ℃ of temperature, 0.5 MPa of oxygen partial pressure, 0.055-0.075mm of particle size, 15:1 of liquid to solid ratio, 120 min of leaching time, 500 r/min of stirring speed and 200 g/L of initial acid concentration. Vanadium and titanium could be selectively separated in the pressure acid leaching process, and the experiment result is in agreement with thermodynamic calculation result. 展开更多
关键词 φ-pH diagram V-Ti-H2O system pressure acid leaching converter slag VANADIUM titanium
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