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The measurement of the energy correlations between two^(252)Cf prompt fission neutrons
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作者 Huai-Yong Bai Hang Li +8 位作者 Hong-Jun Zhang Cheng-Guo Pang Ming Su Zhong-Hua Xiong Ji Wen Fan Gao Chen-Guang Li Xiao-Dong Wang Li-Sheng Yang 《Nuclear Science and Techniques》 2026年第4期202-215,共14页
The energy correlations of prompt fission neutrons have not yet been considered in the related coincidence and multiplication measurement techniques.To measure and verify the energy correlations,an experiment was perf... The energy correlations of prompt fission neutrons have not yet been considered in the related coincidence and multiplication measurement techniques.To measure and verify the energy correlations,an experiment was performed with a total measurement duration of approximately 1200 h.In the experiment,eight CLYC detectors and sixteen EJ309 liquid scintillation detectors were utilized,and the fission moment was tagged with the measured fissionγ-rays.The relative ratios of the energy spectra of the neutrons correlated with different energy neutrons to the^(252)Cf fission neutron energy spectra were obtained.The present results may be helpful for studying fission physics and nuclear technology applications. 展开更多
关键词 Energy correlations Prompt fission neutrons Energy spectrum Fissionγ-rays
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Electronic correlations and topological states at the interface of twisted bilayer graphene and chromium oxychloride
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作者 Minsheng Li Zehao Jia +6 位作者 Xiangyu Cao Qiang Ma Chang Jiang Yuda Zhang Linfeng Ai Pengliang Leng Faxian Xiu 《Chinese Physics B》 2026年第2期185-192,共8页
When two layers of graphene are stacked with a twist angle of approximately 1.1°,strong interlayer coupling gives rise to a pair of flat bands in twisted bilayer graphene(TBG),resulting in pronounced electron–el... When two layers of graphene are stacked with a twist angle of approximately 1.1°,strong interlayer coupling gives rise to a pair of flat bands in twisted bilayer graphene(TBG),resulting in pronounced electron–electron interactions.At half filling of the flat bands,TBG exhibits correlated insulating states.Here,we investigate the electrical transport properties of heterostructures composed of TBG and the antiferromagnetic insulator chromium oxychloride(CrOCl),and propose a strategy to modulate the correlated insulating states in TBG.During the transition from a conventional phase to a strong interfacial coupling phase,kink-like features are observed in the charge neutrality point(CNP),correlated insulating state,and band insulating state.Under a perpendicular magnetic field,the system exhibits broadened quantum Hall plateaus in the strong interfacial coupling regime.Electrons localized in the CrOCl layer screen the bottom gate,rendering the carrier density in TBG less sensitive to variations in the bottom gate voltage.These phenomena are well captured by a charge-transfer model between TBG and CrOCl.Our results provide insights into the control of electronic correlations and topological states in graphene moirésystems via interfacial charge coupling. 展开更多
关键词 twisted bilayer graphene correlated insulating state CrOCl interfacial coupling charge transfer
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Octupole correlations of the K^(π)=5/2^(+)ground-state band in^(229)Th
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作者 Yuan-Yuan Wang Peng-Wei Zhao 《Chinese Physics B》 2026年第2期156-161,共6页
The octupole correlations of the K^(π)=5/2^(+)ground state and the rotational spectrum built on it in^(229)Th are studied using the microscopic relativistic density functional theory on a three-dimensional lattice sp... The octupole correlations of the K^(π)=5/2^(+)ground state and the rotational spectrum built on it in^(229)Th are studied using the microscopic relativistic density functional theory on a three-dimensional lattice space and the reflection-asymmetric triaxial particle rotor model.It is found that^(229)Th has a ground state with static axial octupole and quadrupole deformations.The occurrence of octupole correlations,driven by the octupole deformation,is analyzed through the evolution of single-particle levels around the Fermi surface.The experimental energy spectrum and the electromagnetic transition probabilities,including B(E2)and B(M1),are reasonably well reproduced. 展开更多
关键词 octupole correlation relativistic density functional theory reflection-asymmetric triaxial particle rotor model rotational spectrum
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Recent advances in modelling structure-property correlations in high-entropy alloys 被引量:2
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作者 Akash A.Deshmukh Raghavan Ranganathan 《Journal of Materials Science & Technology》 2025年第1期127-151,共25页
Since antiquity,humans have been involved in designing materials through alloying strategies to meet the ever-growing technological demands.In 2004,this endeavor witnessed a significant breakthrough with the discovery... Since antiquity,humans have been involved in designing materials through alloying strategies to meet the ever-growing technological demands.In 2004,this endeavor witnessed a significant breakthrough with the discovery of high-entropy alloys(HEAs)comprising multi-principal elements.Owing to the four“core-effects”,these alloys exhibit exceptional properties including better structural stability,high strength and ductility,improved fatigue/fracture toughness,high corrosion and oxidation resistance,superconductiv-ity,magnetic properties,and good thermal properties.Different synthesis routes have been designed and used to meet the properties of interest for particular applications with varying dimensions.How-ever,HEAs are providing new opportunities and challenges for computational modelling of the complex structure-property correlations and in predictions of phase stability necessary for optimum performance of the alloy.Several attempts have been made to understand these alloys by empirical and computa-tional models,and data-driven approaches to accelerate the materials discovery with a desired set of properties.The present review discusses advances and inferences from simulations and models spanning multiple length and time scales explaining a comprehensive set of structure-properties relations.Addi-tionally,the role of machine learning approaches is also reviewed,underscoring the transformative role of computational modelling in unravelling the multifaceted properties and applications of HEAs,and the scope for future efforts in this direction. 展开更多
关键词 High-entropy alloys DFT Molecular dynamics CALPHAD Machine learning Structure-property correlations
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Utilizing On-the-Go Soil Sensors to Explore Correlations between Electrical Conductivity, Soil Reflectance, Slope, and Elevation of Mississippi Farm Soils 被引量:1
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作者 Reginald S. Fletcher 《Agricultural Sciences》 2025年第1期112-122,共11页
Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the m... Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the measurements. At MF3E, moderate variability was observed in apparent electrical conductivity shallow (ECas), slope, and ECa ratio measurements, with coefficients of variation ranging from 20% to 27%. In contrast, MF11S exhibited higher variability, particularly in ECas and ECad (deep) measurements, which exceeded 30% in their coefficient of variation values, indicating significant differences in soil composition and moisture content. Correlation analysis revealed strong positive relationships between the near-infrared-to-red ratio and red reflectance (r = 0.897***) soil values at MF3E. MF11S demonstrated a strong negative correlation between ECas and ECad readings with the x-coordinate (r ***). Scatter plots and fitted models illustrated the complexity of relationships, with many showing nonlinear trends. These findings emphasize the need for continuous monitoring and advanced modeling to understand the dynamic nature of soil properties and their implications for agricultural practices. Future research should explore the underlying mechanisms driving variability in the soil characteristics to enhance soil management strategies at the study sites. 展开更多
关键词 Mobile Soil Sensors NEAR-INFRARED Correlation Nonlinear
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Correlations of resilience with coping styles and quality of life in patients with malignancies 被引量:1
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作者 Xue-Jin Qin Man-Man Kang +4 位作者 Fei Zhong Jing-Jing Liu Zheng-Chun Zhu Di Zhang Ke Han 《World Journal of Psychiatry》 2025年第4期186-194,共9页
BACKGROUND Resilience is an individual’s ability and psychological rebound capacity to adapt well after experiencing adversity,trauma,etc.Patients with strong resilience can face illnesses actively.AIM To determine t... BACKGROUND Resilience is an individual’s ability and psychological rebound capacity to adapt well after experiencing adversity,trauma,etc.Patients with strong resilience can face illnesses actively.AIM To determine the association of resilience with coping styles and quality of life in patients with malignancies.METHODS This study included patients with malignant tumors who were hospitalized at Fuyang Hospital Affiliated to Anhui Medical University from March 2022 to March 2024.The Connor-Davidson Resilience Scale,Medical Coping Modes Questionnaire,Social Support Rating Scale,and the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 were utilized to assess patients’resilience,coping styles,social support,and quality of life,respectively.Pearson correlation analysis was conducted to assess the correlations.RESULTS A total of 175 patients with malignant tumors demonstrated no marked difference in terms of age,education level,employment status,monthly household income,and disease staging(P<0.05).Further,patients with malignancies demonstrated scores of 17.49±1.20,17.27±1.46,and 11.19±1.29 points in terms of coping styles in confrontation,avoidance,and resignation dimensions,respectively.Subjective support,objective support,and support utilization scores in terms of social support were 10.67±1.80,11.26±2.08,and 9.24±1.14 points,respectively.The total resilience score and tenacity,self-improvement,and optimism dimension scores were positively correlatedwith the confrontation coping style score,whereas the total resilience score and tenacity and self-improvementscores were negatively associated with avoidance and resignation coping style scores(P<0.05).The total resiliencescore and the tenacity dimension score were positively associated with physical,role,cognitive,emotional,andsocial functions,as well as global health status(P<0.05),and were inversely related to fatigue,insomnia,andeconomic difficulties(P<0.05).CONCLUSIONThe resilience of patients with malignancies is positively associated with the confrontation dimension in the copingstyle,the total and various social support domain scores,and the overall quality of life.Clinical medical staff needto pay attention to the effect of medical coping styles and social support on the resilience level of patients withmalignancies to further improve their quality of life. 展开更多
关键词 Malignant tumor RESILIENCE Coping style Quality of life CORRELATION
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Correlations of the expression of Cx43,SCF^(FBXW7),p-cyclin E1(Ser73),p-cyclin E1(Thr77)and p-cyclin E1(Thr395)in colon cancer tissues
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作者 Rong-Gang Luan Ming-Da Liu +9 位作者 Zi-Feng Deng Cong-Lan Lu Mei-Ling Yu Ming-Yu Zhang Rong Liu Ran An You-Liang Yao Dong-Bei Guo Yong-Xing Zhang Lei Zhao 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期207-213,共7页
BACKGROUND Previous cellular studies have demonstrated that elevated expression of Cx43 promotes the degradation of cyclin E1 and inhibits cell proliferation through ubiquitination.Conversely,reduced expression result... BACKGROUND Previous cellular studies have demonstrated that elevated expression of Cx43 promotes the degradation of cyclin E1 and inhibits cell proliferation through ubiquitination.Conversely,reduced expression results in a loss of this capacity to facilitate cyclin E degradation.The ubiquitination and degradation of cyclin E1 may be associated with phosphorylation at specific sites on the protein,with Cx43 potentially enhancing this process by facilitating the phosphorylation of these critical residues.AIM To investigate the correlation between expression of Cx43,SKP1/Cullin1/F-box(SCF)FBXW7,p-cyclin E1(ser73,thr77,thr395)and clinicopathological indexes in colon cancer.METHODS Expression levels of Cx43,SCF^(FBXW7),p-cyclin E1(ser73,thr77,thr395)in 38 clinical colon cancer samples were detected by immunohistochemistry and were analyzed by statistical methods to discuss their correlations.RESULTS Positive rate of Cx43,SCF^(FBXW7),p-cyclin E1(Ser73),p-cyclin E1(Thr77)and p-cyclin E1(Thr395)in detected samples were 76.32%,76.32%,65.79%,5.26%and 55.26%respectively.Positive expressions of these proteins were not related to the tissue type,degree of tissue differentiation or lymph node metastasis.Cx43 and SCF^(FBXW7)(r=0.749),p-cyclin E1(Ser73)(r=0.667)and p-cyclin E1(Thr395)(r=0.457),SCF^(FBXW7) and p-cyclin E1(Ser73)(r=0.703)and p-cyclin E1(Thr395)(0.415)were correlated in colon cancer(P<0.05),and expressions of the above proteins were positively correlated in colon cancer.CONCLUSION Cx43 may facilitate the phosphorylation of cyclin E1 at the Ser73 and Thr195 sites through its interaction with SCF^(FBXW7),thereby influencing the ubiquitination and degradation of cyclin E1. 展开更多
关键词 Colon cancer CX43 SCF^(FBXW7) Phosphorylation of cyclin E1 Sites of cyclin E1 Correlation analysis
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Application of Multiple Correlations Analysis in Portfolio Selection
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作者 Ruili Sun Junpeng Jia Shiguo Huang 《Proceedings of Business and Economic Studies》 2025年第4期305-319,共15页
Portfolio selection based on the global minimum variance(GMV)model remains a significant focus in financial research.The covariance matrix,central to the GMV model,determines portfolio weights,and its accurate estimat... Portfolio selection based on the global minimum variance(GMV)model remains a significant focus in financial research.The covariance matrix,central to the GMV model,determines portfolio weights,and its accurate estimation is key to effective strategies.Based on the decomposition form of the covariance matrix.This paper introduces semi-variance for improved financial asymmetric risk measurement;addresses asymmetry in financial asset correlations using distance,asymmetric,and Chatterjee correlations to refine covariance matrices;and proposes three new covariance matrix models to enhance risk assessment and portfolio selection strategies.Testing with data from 30 stocks across various sectors of the Chinese market confirms the strong performance of the proposed strategies. 展开更多
关键词 Portfolio selection GMV model Semi-variance Asymmetric correlation Chatterjee correlation
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Observable-manifested correlations in many-body quantum chaotic systems
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作者 Xiao Wang Jiaozi Wang Wen-ge Wang 《Communications in Theoretical Physics》 2025年第12期143-151,共9页
In this paper,we investigate the distinctions between dynamical quantum chaotic systems and random models from the perspective of observable properties,particularly focusing on the eigenstate thermalization hypothesis... In this paper,we investigate the distinctions between dynamical quantum chaotic systems and random models from the perspective of observable properties,particularly focusing on the eigenstate thermalization hypothesis(ETH).Through numerical simulations,we find that for dynamical systems,the envelope function of off-diagonal elements of observables exhibits an exponential decay at largeΔE,while for randomized models,it tends to be flat.We demonstrate that the correlations of chaotic eigenstates,originating from the delicate structures of Hamiltonians,play a crucial role in the non-trivial structure of the envelope function.Furthermore,we analyze the numerical results from the perspective of the dynamical group elements in Hamiltonians.Our findings highlight the importance of correlations in physical chaotic systems and provide insights into the deviations from random matrix theory(RMT)predictions.These understandings offer valuable directions for future research. 展开更多
关键词 eigenstate thermalization quantum chaos many body correlations
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Correlations of the net baryon number and electric charge in nuclear matter
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作者 Xin-Ran Yang Guo-Yun Shao +1 位作者 Chong-Long Xie Zhi-Peng Li 《Nuclear Science and Techniques》 2025年第8期154-164,共11页
We investigated the correlations between the net baryon number and electric charge up to the sixth order related to the interactions of nuclear matter at low temperature and explored their relationship with the nuclea... We investigated the correlations between the net baryon number and electric charge up to the sixth order related to the interactions of nuclear matter at low temperature and explored their relationship with the nuclear liquid-gas phase transition(LGPT)within the framework of the nonlinear Walecka model.The calculations showed that strong correlations between the baryon number and electric charge existed near the LGPT,and higher-order correlations were more sensitive than the lower-order correlations near the phase transition.However,in the high-temperature region away from the LGPT,the rescaled lower-order correlations were relatively larger than most of the higher-order correlations.In addition,some of the fifth-and sixth-order correlations possibly changed sign from negative to positive along the chemical freeze-out line with decreasing temperature.In combination with future experimental projects at lower collision energies,the derived results can be used to study the phase structure of strongly interacting matter and analyze the related experimental signals. 展开更多
关键词 correlations of conserved charges Nuclear matter Nuclear liquid–gas phase transition Heavy-ion collision
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Towards understanding the microstructure-mechanical property correlations of multi-level heterogeneous-structured Al matrix composites
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作者 Yuesong Wu Xiaobin Lin +4 位作者 Xudong Rong Xiang Zhang Dongdong Zhao Chunnian He Naiqin Zhao 《Journal of Materials Science & Technology》 2025年第6期117-123,共7页
1.Introduction The strength-ductility trade-offdilemma has long been a per-sistent challenge in Al matrix composites(AMCs)[1,2].This is-sue primarily arises from the agglomeration of reinforcements at the grain bounda... 1.Introduction The strength-ductility trade-offdilemma has long been a per-sistent challenge in Al matrix composites(AMCs)[1,2].This is-sue primarily arises from the agglomeration of reinforcements at the grain boundaries(GBs),which restricts local plastic flow dur-ing the plastic deformation and leads to stress concentration[3,4].Recently,the development of concepts aimed at achieving hetero-geneous grain has emerged as a promising approach for enhanc-ing comprehensive mechanical properties[5,6]. 展开更多
关键词 reinforcements agglomeration comprehensive mechanical properties agglomeration reinforcements plastic deformation strength ductility trade off multi level heterogeneous structured Al matrix composites microstructure mechanical property correlations al matrix composites amcs
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The impact of tensor force on collective correlations and neutrinoless double-βdecay
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作者 Chang-Feng Jiao Cen-Xi Yuan 《Nuclear Science and Techniques》 2025年第11期233-242,共10页
The tensor force changes the nuclear shell structure and thus may result in underlying influence of the collectivity and decay properties of the nucleus.We carefully examined the impact of the monopole and multipole e... The tensor force changes the nuclear shell structure and thus may result in underlying influence of the collectivity and decay properties of the nucleus.We carefully examined the impact of the monopole and multipole effects originating from the tensor force on both the collectivity and the matrix element for the neutrinoless double-β(0νββ)decay,using the generatorcoordinate method with an effective interaction.To analyze the effect of the tensor force,we employed an effective Hamiltonian associated with the monopole-based universal interaction that explicitly consists of the central,tensor,and spin-orbit coupling terms.The interferences among the shell structure,quadrupole collectivity,nucleon occupancy,and 0νββmatrix elements were analyzed in detail.A better understanding of the tensor force would be of great importance in reducing the theoretical uncertainty in 0νββnuclear matrix element calculations. 展开更多
关键词 Neutrinoless double-beta decay Collective correlations Tensor force
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Canopy structural heterogeneity drives α and β species-genetic diversity correlations in a Chinese subtropical forest
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作者 Zhiliang Yao Xia Pan +6 位作者 Xin Yang Xiaona Shao Bin Wang Yun Deng Zhiming Zhang Qiaoming Li Luxiang Lin 《Plant Diversity》 2025年第1期106-114,共9页
Patterns and drivers of species–genetic diversity correlations(SGDCs)have been broadly examined across taxa and ecosystems and greatly deepen our understanding of how biodiversity is maintained.However,few studies ha... Patterns and drivers of species–genetic diversity correlations(SGDCs)have been broadly examined across taxa and ecosystems and greatly deepen our understanding of how biodiversity is maintained.However,few studies have examined the role of canopy structural heterogeneity,which is a defining feature of forests,in shaping SGDCs.Here,we determine what factors contribute toα-andβ-species–genetic diversity correlations(i.e.,α-andβ-SGDCs)in a Chinese subtropical forest.For this purpose,we used neutral molecular markers to assess genetic variation in almost all adult individuals of the dominant tree species,Lithocarpus xylocarpus,across plots in the Ailaoshan National Natural Reserve.We also quantified microhabitat variation by quantifying canopy structure heterogeneity with airborne laser scanning on 201-ha subtropical forest plots.We found that speciesα-diversity was negatively correlated with geneticα-diversity.Canopy structural heterogeneity was positively correlated with speciesα-diversity but negatively correlated with geneticα-diversity.These contrasting effects contributed to the formation of a negativeα-SGDC.Further,we found that canopy structural heterogeneity increases speciesα-diversity and decreases geneticα-diversity by reducing the population size of target species.Speciesβ-diversity,in contrast,was positively correlated with geneticβ-diversity.Differences in canopy structural heterogeneity between plots had non-linear parallel effects on the two levels ofβ-diversity,while geographic distance had a relatively weak effect onβ-SGDC.Our study indicates that canopy structural heterogeneity simultaneously affects plot-level community species diversity and population genetic diversity,and species and genetic turnover across plots,thus drivingα-andβ-SGDCs. 展开更多
关键词 Dominant species Forest structure LIDAR Lithocarpus xylocarpus Speciesegenetic diversity correlation Subtropical evergreen broad-leaved forest
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Cross-correlations between signal's components
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作者 Quankun Zhao Sen Li +2 位作者 Changgui Gu Haiying Wang Huijie Yang 《Chinese Physics B》 2025年第2期483-494,共12页
Detecting coupling pattern between elements in a complex system is a basic task in data-driven analysis. The trajectory for each specific element is a cooperative result of its intrinsic dynamic, its couplings with ot... Detecting coupling pattern between elements in a complex system is a basic task in data-driven analysis. The trajectory for each specific element is a cooperative result of its intrinsic dynamic, its couplings with other elements, and the environment. It is subsequently composed of many components, only some of which take part in the couplings. In this paper we present a framework to detect the component correlation pattern. Firstly, the interested trajectories are decomposed into components by using decomposing methods such as the Fourier expansion and the Wavelet transformation. Secondly, the cross-correlations between the components are calculated, resulting into a component cross-correlation matrix(network).Finally, the dominant structure in the network is identified to characterize the coupling pattern in the system. Several deterministic dynamical models turn out to be characterized with rich structures such as the clustering of the components. The pattern of correlation between respiratory(RESP) and ECG signals is composed of five sub-clusters that are mainly formed by the components in ECG signal. Interestingly, only 7 components from RESP(scattered in four sub-clusters) take part in the realization of coupling between the two signals. 展开更多
关键词 coupling structure cross-correlation matrix component correlation network
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Detailed discussion of discrepancy between theoretical and observed spectral lines in Kr-like W^(38+)based on advanced consideration of core electron correlations
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作者 Guo-Qing Peng Kai Wang +1 位作者 Jun Yan Wei Kang 《Chinese Physics B》 2025年第5期328-337,共10页
For the observed line at 799.23°A in tungsten EBIT experiment,which was assigned to be^(3)F_(4)^(o)−^(3)F_(3)^(o)([Ar]4s^(2)4p^(5)4d)of W^(38+)ion,there were noticeable deviations for most calculated wavelengths ... For the observed line at 799.23°A in tungsten EBIT experiment,which was assigned to be^(3)F_(4)^(o)−^(3)F_(3)^(o)([Ar]4s^(2)4p^(5)4d)of W^(38+)ion,there were noticeable deviations for most calculated wavelengths from the measured value.To clarify this issue,we carry out an extensive calculation for energy levels and transition properties of W^(38+)ion using the multi-configuration Dirac–Hartree–Fock and relativistic configuration interaction method,in which more deeper inner core electron correlations are included,and different forms of Breit interaction as well as quantum electrodynamics corrections are investigated.It is found that the inner core electron correlations can affect the total energy of levels,while only slightly modify the excited energy of levels in 4s^(2)4p^(5)4d complex.The present calculated wavelengths agree with the corresponding measured values excellently except the line at 799.23Å.Thus we are strongly suspicious this line should be misidentified,and suggest that new experiment with higher resolution and spectra analysis based on more accurate atomic data should be performed for W^(38+)ion. 展开更多
关键词 Kr-like W^(38+) the multi-configuration Dirac-Hartree-Fock(MCDHF)method electron correlation imbalance Breit interaction quantum electrodynamic(QED)
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上行相关性、下行相关性与收益率预测
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作者 郑振龙 杨玉晓 陈蓉 《数理统计与管理》 北大核心 2026年第1期147-160,共14页
投资者在股票市场进行分散投资时,仍然承担着股票间的相关性风险,研究相关性风险与预期收益率的关系,对投资组合的选择有重要的参考意义。本文首次把相关性风险分解为上行相关性和下行相关性,然后利用日内高频数据,分析了它们对未来不... 投资者在股票市场进行分散投资时,仍然承担着股票间的相关性风险,研究相关性风险与预期收益率的关系,对投资组合的选择有重要的参考意义。本文首次把相关性风险分解为上行相关性和下行相关性,然后利用日内高频数据,分析了它们对未来不同期限中国股票市场收益率的预测能力。实证结果发现:(1)相关性风险对股票市场未来不同期限收益率有负向预测力。(2)相关性对中长期整体市场收益率预测表现更佳,在对未来六个月和一年的沪深300样本内预测R^(2)超过了7%。(3)结合样本内和样本外的预测结果,与总的相关性和上行相关性相比,下行相关性对股票市场收益率的预测能力更稳健,尤其是样本外预测效果更优。为了进一步说明相关性稳健的预测能力,我们还考察了上证50,结果显示相关性对其仍保持着预测能力。相关性风险是投资者不可忽视的风险,特别是下行相关性风险。 展开更多
关键词 上行相关性 下行相关性 收益率预测
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黑河干流景观格局对底栖动物的影响
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作者 张宝泉 李能安 +1 位作者 王昱 刘开清 《干旱区研究》 北大核心 2026年第2期398-409,共12页
景观格局对内陆河生物多样性的影响程度和机制对于干旱区内陆河河流生态系统保护具有重要意义。本文以黑河干流为研究对象,基于景观格局数据和底栖动物数据,采用冗余分析和相关性分析探究了不同缓冲区下景观格局和底栖动物之间的关系。... 景观格局对内陆河生物多样性的影响程度和机制对于干旱区内陆河河流生态系统保护具有重要意义。本文以黑河干流为研究对象,基于景观格局数据和底栖动物数据,采用冗余分析和相关性分析探究了不同缓冲区下景观格局和底栖动物之间的关系。结果表明:底栖动物的现存量和生物多样性在空间上均表现为中游>上游,在时间上均表现为夏季>秋季;河岸带缓冲区景观组成主要以草地、未利用地和耕地为主,在600 m缓冲区内景观类型丰富且空间异质性强;耕地有利于耐污类群和刮食者生存,草地有利于清洁型物种和捕食者生存;景观指数PD和SHDI与底栖动物现存量和生物多样性呈正相关,而CONTAG与底栖动物现存量和生物多样性呈负相关;冗余分析表明,600 m河岸带缓冲区是景观格局对底栖动物群落影响最为显著的空间尺度。因此,在该尺度范围内应重点关注景观要素的合理配置,通过提升中游区域林草植被的种植密度、聚集程度与景观连通性,有助于增强干旱内陆河流域的生物多样性水平。 展开更多
关键词 黑河 相关性分析 景观格局 底栖动物
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不同发酵温度对鲊广椒滋味品质及微生物群落的影响
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作者 王玉荣 王鑫 +3 位作者 圣群航 张海波 侯强川 郭壮 《轻工学报》 北大核心 2026年第1期16-25,共10页
【目的】揭示不同发酵温度对鲊广椒滋味品质及微生物群落的影响。【方法】采用电子舌技术对不同发酵温度(20℃、25℃、30℃和35℃)下鲊广椒的滋味品质进行评价,并结合MiSeq高通量测序技术对其微生物群落结构进行解析,最后基于普氏分析... 【目的】揭示不同发酵温度对鲊广椒滋味品质及微生物群落的影响。【方法】采用电子舌技术对不同发酵温度(20℃、25℃、30℃和35℃)下鲊广椒的滋味品质进行评价,并结合MiSeq高通量测序技术对其微生物群落结构进行解析,最后基于普氏分析对微生物群落与滋味品质进行关联性分析。【结果】不同发酵温度下,鲊广椒的滋味品质和微生物群落结构均存在显著性差异(P<0.05),主要细菌属为乳杆菌属(Lactobacillus)和芽孢杆菌属(Bacillus),主要真菌属为生丝毕赤酵母属(Hyphopichia)、曲霉菌属(Aspergillus)、枝孢菌属(Cladosporium)、赤霉菌属(Gibberella)、柯达酵母属(Kodamaea)和季也蒙酵母属(Meyerozyma),其中20℃发酵鲊广椒的酸味更为突出,微生物种类更优,乳杆菌属为其主要优势细菌属,生丝毕赤酵母属为其主要优势真菌属,不动杆菌属(Acinetobacter)、罗森伯格氏菌属(Rosenbergiella)和枝孢菌属为区别于其他3组微生物群落结构的关键菌属;鲊广椒的微生物群落与滋味指标之间存在显著相关性(P<0.05),且优势微生物之间的相互作用共同促进了鲊广椒滋味特征的构建。【结论】20℃发酵鲊广椒的微生物群落丰富度和滋味品质均较好。 展开更多
关键词 鲊广椒 发酵温度 微生物群落 滋味品质 相关性
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大豆的营养成分对南溪豆腐干加工品质的影响
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作者 刘一静 黄昕怡 +3 位作者 狄飞达 张驰松 冯骏 方秋野 《粮食与油脂》 北大核心 2026年第3期57-62,共6页
选取不同大豆品种,研究大豆营养成分(粗蛋白质、粗脂肪、水分)与豆腐干加工品质之间的关系。结果表明:10个大豆品种粗蛋白质含量变异系数小,粗脂肪和水分含量变异系数大。豆腐干得率为186.71~263.34 g/100 g,持水性为53.20%~60.10%,水... 选取不同大豆品种,研究大豆营养成分(粗蛋白质、粗脂肪、水分)与豆腐干加工品质之间的关系。结果表明:10个大豆品种粗蛋白质含量变异系数小,粗脂肪和水分含量变异系数大。豆腐干得率为186.71~263.34 g/100 g,持水性为53.20%~60.10%,水分含量为57.76%~64.58%。质构特性指标中硬度、脆度等变异程度稍大,弹性等与品质相关指标的变异程度较小。而且豆腐干得率、持水性与大豆的粗蛋白质含量均呈正相关(r=0.728、r=0.400),持水性与粗脂肪含量也呈正相关(r=0.375);豆腐干多项质构特性与粗蛋白质含量呈正相关,弹性和内聚性与粗脂肪含量呈正相关。通过聚类分析发现,大豆2291、2115、2242、2171和桂夏7号制作的豆腐干具有较好的综合品质。 展开更多
关键词 不同大豆品种 营养成分 豆腐干 相关性分析
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孕早中期血清内皮素-1、脂联素表达与子痫前期发生风险的关系
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作者 曹丹 李婕娜 +3 位作者 李叶 桑爱红 张玉珠 何晓翠 《中国妇产科临床杂志》 北大核心 2026年第1期52-55,共4页
目的探讨孕早中期血清内皮素、脂联素表达与子痫前期发生风险的关系。方法回顾性收集2023年1月至2025年1月于菏泽市立医院建档并完成分娩的538例孕妇的临床资料,根据妊娠期间是否发生子痫前期分为发生组(n=32)与未发生组(n=506)。比较... 目的探讨孕早中期血清内皮素、脂联素表达与子痫前期发生风险的关系。方法回顾性收集2023年1月至2025年1月于菏泽市立医院建档并完成分娩的538例孕妇的临床资料,根据妊娠期间是否发生子痫前期分为发生组(n=32)与未发生组(n=506)。比较两组孕早中期血清内皮素-1、脂联素水平、血清内皮素-1差值(S内皮素-1)及脂联素差值(S脂联素),分析孕早中期血清内皮素-1、脂联素水平与子痫前期发生风险的关系。结果与未发生组相比,发生组孕早中期血清内皮素-1水平较高,血清脂联素水平较低,S内皮素-1、S脂联素较大(P<0.05);发生组孕中期血清内皮素-1水平高于孕早期,脂联素水平低于孕早期(P<0.05)。Logistic回归分析显示,孕早中期内皮素-1、脂联素水平及S内皮素-1、S脂联素值均为孕妇子痫前期发生的影响因素(P<0.05)。限制性立方样条法(RCS)分析显示,孕妇子痫前期发生的风险与孕早中期内皮素-1、脂联素及S内皮素-1和S脂联素水平呈非线性-剂量反应关系。结论孕早中期血清内皮素-1和脂联素水平的动态变化可辅助临床早期识别子痫前期高风险群体。 展开更多
关键词 子痫前期 内皮素 脂联素 相关性
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