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Correction:A Valuable and Low‑Budget Process Scheme of Equivalized 1 nm Technology Node Based on 2D Materials
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作者 Yang Shen Zhejia Zhang +6 位作者 Zhujun Yao Mengge Jin Jintian Gao Yuhan Zhao Wenzhong Bao Yabin Sun He Tian 《Nano-Micro Letters》 2025年第11期717-720,共4页
Correction to:Nano-Micro Letters(2025)17:191 https://doi.org/10.1007/s40820-025-01702-7 Following the publication of the original article[1],the authors reported an error in Fig.3(b),and the figure legend was reversed... Correction to:Nano-Micro Letters(2025)17:191 https://doi.org/10.1007/s40820-025-01702-7 Following the publication of the original article[1],the authors reported an error in Fig.3(b),and the figure legend was reversed.The correct Fig.3 has been provided in this orrection. 展开更多
关键词 equivalized nano micro letters process scheme D materials low budget figure legend error CORRECTION nm technology node
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A new scheme for isomer pumping and depletion with high-power lasers
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作者 C.-J.Yang K.M.Spohr +3 位作者 M.O.Cernaianu D.Doria P.Ghenuche V.Horny 《Matter and Radiation at Extremes》 2025年第5期1-9,共9页
We propose a novel scheme for the population and depletion of nuclear isomers.This scheme combines the γ photons with energiesà 10 keV emitted during the interaction of a contemporary high-intensity laser pulse ... We propose a novel scheme for the population and depletion of nuclear isomers.This scheme combines the γ photons with energiesà 10 keV emitted during the interaction of a contemporary high-intensity laser pulse with a plasma and one or multiple photon beams supplied by intense lasers.Owing to nonlinear effects,two-or multiphoton absorption dominates over the conventional multistep one-photon process for an optimized γ flash.Moreover,this nonlinear effect can be greatly enhanced with the help of externally supplied low-energy photons coming from another laser.These low-energy photons act such that the effective cross-section experienced by the γ photons becomes tunable,growing with the intensity I_(0) of the beam.Assuming I_(0)~10^(18) W·cm^(-2) for the photon beam,an effective cross-section as large as 10^(-21)-10^(-28) cm^(2) for the γ photons can be achieved.Thus,with state-of-the-art 10 PW laser facilities,the yields from two-photon absorption can reach 10^(6)-10^(9) isomers per shot for selected states that are separated from their ground state by E2 transitions.Similar yields for transitions with higher multipolarities can be accommodated by multiphoton absorption with additional photons provided. 展开更多
关键词 isomer pumping externally suppl two photon absorption high power lasers multiphoton absorption depletion scheme nonlinear effects intense lasersowing
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Corrigendum to“Evolution of multi-cluster fracturing in high-density layered shale considering the effect of injection scheme”[Pet.Sci.22(2025)2109-2122]
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作者 Xiao Yan Haitao Yu Peng Zhang 《Petroleum Science》 2025年第7期3068-3068,共1页
The authors regret Acknowledgements Firstly,the authors wish to acknowledge the academic support from Ruhr University Bochum during the first author's(Xiao Yan)research stay from 2018.11 to 2020.10,including the s... The authors regret Acknowledgements Firstly,the authors wish to acknowledge the academic support from Ruhr University Bochum during the first author's(Xiao Yan)research stay from 2018.11 to 2020.10,including the soft code implement and debug support from Vladislav Gudzulic and academic advising from Günther Meschke. 展开更多
关键词 research stay academic advising soft code implement debug support high density layered shale evolution injection scheme academic support multi cluster fracturing
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Laser-plasma acceleration of quasi-monoenergetic carbon ion beams with the“peeler”scheme
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作者 Bogdan Corobean Vojtech Horny +4 位作者 Alexander Pukhov Emmanuel d’Humieres Domenico Doria Calin Alexandru Ur Paolo Tomassini 《Matter and Radiation at Extremes》 2025年第5期28-37,共10页
We introduce a scheme aiming at the generation of quasi-monochromatic carbon ion bunches from laser-solid interaction.The proposed scheme is an extension of the“peeler”acceleration originally proposed for proton acc... We introduce a scheme aiming at the generation of quasi-monochromatic carbon ion bunches from laser-solid interaction.The proposed scheme is an extension of the“peeler”acceleration originally proposed for proton acceleration,which involves irradiating the narrow(submicrometer)side of a tape target.This results in the generation of a surface plasma wave and the subsequent acceleration of a proton bunch with high peak energy,quasi-monochromaticity,low energy bandwidth,and low divergence by the electrostatic field induced at the target rear.Up to now,the higher-Z(e.g.,carbon)ion bunches obtained with the peeler scheme have been found to exhibit an exponentially decaying thermal-like energy spectrum.To achieve a low energy bandwidth,we place a mass-limited carbon structure at the rear of the target.Using 3D particle-in-cell simulations,we show that a quasi-monochromatic carbon bunch can indeed be obtained.With a multi-PW laser pulse,10^(8) carbon ions with peak energy~110 MeV/u and with a divergence of 20° in the vertical plane and~1° in the horizontal plane can be generated.The quasi-monochromaticity,together with the low duration of the beam and in combination with the versatility of high-power laser facilities,should make this scheme attractive for practical applications such as heavy ion cancer therapy and higher-resolution diagnostics of extreme plasma states. 展开更多
关键词 carbon ion quasi monochromatic carbon ion beams electrostatic fie acceleration proton bunch generation surface plasma wave high power laser facilities tape targetthis peeler scheme
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S-scheme活性炭负载g-C_(3)N_(4)/TiO_(2)光催化混凝土降解性能分析
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作者 张典 《无机盐工业》 北大核心 2025年第4期118-127,共10页
为了解决抗生素废水污染和室内装修低浓度甲醛污染,采用简易的混合高温煅烧法制备了活性炭负载g-C_(3)N_(4)/TiO_(2)(g-C_(3)N_(4)/TiO_(2)/AC)复合光催化剂。通过XRD、XPS、TEM、UV-vis DRS和PL等技术对复合光催化剂的物相晶型、元素... 为了解决抗生素废水污染和室内装修低浓度甲醛污染,采用简易的混合高温煅烧法制备了活性炭负载g-C_(3)N_(4)/TiO_(2)(g-C_(3)N_(4)/TiO_(2)/AC)复合光催化剂。通过XRD、XPS、TEM、UV-vis DRS和PL等技术对复合光催化剂的物相晶型、元素组成、微观形貌、光谱响应范围和光生载流子重组等进行了表征。S-scheme异质结弯曲能带和内电场实现了光生载流子的高效分离,拓宽了光谱吸收范围,有效保留了高活性的·O_(2)^(-)、h^(+)和·OH等活性基团,表现出优异的磺胺甲基噻唑(STZ)降解活性和稳定性,g-C_(3)N_(4)/TiO_(2)/AC投加量为1.0 mg和STZ初始质量浓度为100 mg/L条件下,可见光照射30 min时STZ降解率为98.8%,明显优于g-C_(3)N_(4)、TiO_(2)和TiO_(2)/AC。g-C_(3)N_(4)/TiO_(2)/AC掺杂到环氧树脂涂料中合成了光催化涂料,通过空气喷枪均匀喷涂到混凝土表面得到光催化混凝土,光催化混凝土表现出良好的甲醛降解活性和稳定性,g-C_(3)N_(4)/TiO_(2)/AC负载量为3%、甲醛初始质量浓度为1000 mg/L、可见光照射180 min时,甲醛降解率达到了96.3%,有效实现了室内装修低浓度甲醛气体的高效降解。 展开更多
关键词 g-C_(3)N_(4) TiO_(2) S-scheme电荷转移机制
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Considering for the blanket structure scheme of HCCB DEMO 被引量:2
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作者 Zhou Zhao Zaixin Li +2 位作者 Xiaoyu Wang Xueren Wang Kaiming Feng 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第3期188-194,共7页
For the solid blanket concept of helium cooled ceramic breeder (HCCB) demonstration fusion power plant (DEMO), a feasible blanket structure with configuration 2×X is proposed as considering relatively low tempera... For the solid blanket concept of helium cooled ceramic breeder (HCCB) demonstration fusion power plant (DEMO), a feasible blanket structure with configuration 2×X is proposed as considering relatively low temperature limit of neutron multiplier beryllium pebbles. Based on that, preliminary design for the typical blanket module of HCCB DEMO has been carried out and verified by thermal-hydraulic analysis and structural analysis. Furthermore, the specific relationship of maximum temperature depended on the surface heating of blanket key part first wall (FW) is also analyzed. 展开更多
关键词 HELIUM cooled ceramic BREEDER (HCCB) Demonstration fusion power plant (DEMO) BLANKET structure scheme Preliminary design and analysis
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A conservative wavelet upwind scheme for compressible flows
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作者 Bing Yang Xiaojing Liu +1 位作者 Youhe Zhou Jizeng Wang 《Acta Mechanica Sinica》 2025年第7期149-167,共19页
In this paper,we develop a fourth-order conservative wavelet-based shock-capturing scheme.The scheme is constructed by combining a wavelet collocation upwind method with the monotonic tangent of hyperbola for interfac... In this paper,we develop a fourth-order conservative wavelet-based shock-capturing scheme.The scheme is constructed by combining a wavelet collocation upwind method with the monotonic tangent of hyperbola for interface capturing(THINC)technique.We employ boundary variation diminishing(BVD)reconstruction to enhance the scheme’s effectiveness in handling shocks.First,we prove that wavelet collocation upwind schemes based on interpolating wavelets can be reformulated into a conservative form within the framework of wavelet theory,forming the foundation of the proposed scheme.The new fourthorder accurate scheme possesses significantly better spectral resolution than the fifth-and even seventh-order WENO-Z(weighted essentially non-oscillatory)schemes over the entire wave-number range.Moreover,the inherent low-pass filtering property of the wavelet bases allows them to filter high-frequency numerical oscillations,endowing the wavelet upwind scheme with robustness and accuracy in solving problems under extreme conditions.Notably,due to the wavelet multiresolution approximation,the proposed scheme possesses a distinctive shape-preserving property absent in the WENO-Z schemes and the fifth-order schemes with BVD reconstruction based on polynomials.Furthermore,compared to the fifth-order scheme with BVD reconstruction based on polynomials—which is significantly superior to the WENO schemes—the proposed scheme further enhances the ability to capture discontinuities. 展开更多
关键词 Conservative wavelet upwind scheme Boundary variation diminishing THINC scheme HIGH-RESOLUTION Compressible flows
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Construction and application of composite insulation scheme in the perioperative period of patients undergoing laparoscopic colorectal cancer surgery
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作者 Ling-Jun Du Yan-Guang Su +2 位作者 Zhu-Hua Shen Yan-Li Zhang Yong-Yi Ma 《World Journal of Gastrointestinal Surgery》 2025年第5期266-274,共9页
BACKGROUND Elderly patients undergoing laparoscopic colorectal cancer surgery are at high risk for hypothermia-related complications.This study explores the efficacy of periop-erative composite insulation intervention... BACKGROUND Elderly patients undergoing laparoscopic colorectal cancer surgery are at high risk for hypothermia-related complications.This study explores the efficacy of periop-erative composite insulation interventions in maintaining normothermia and reducing postoperative risks in this vulnerable group.AIM To evaluate the efficacy of perioperative composite insulation in older patients undergoing colorectal cancer surgery.METHODS We selected 100 older patients who underwent laparoscopic surgery for colorectal cancer at Huzhou Central Hospital from September 2023 to April 2024.Using a random number table,patients were divided into a control group and inter-vention group of 50 patients each.After returning to the regular ward,the con-ventional group received traditional insulation intervention measures,while the intervention group received composite insulation nursing intervention.We ob-served and recorded postoperative blood pressure and heart rate changes,as well as postoperative anesthesia recovery time and incidence of complications.RESULTS The statistical results showed significant differences(P<0.05)in heart rate changes and systolic blood pressure between the two groups.There was a sig-nificant change in heart rate between the groups immediately after surgery and at 15 and 30 minutes after surgery(P<0.05).The heart rate and systolic blood pressure of the intervention group were significantly lower than those of the control group at 15 and 30 minutes after surgery(P<0.05).The rewarming time of the intervention group was shorter than that of the control group,and the overall incidence of postoperative complications was significantly lower than that of the control group(P<0.05).CONCLUSION For elderly patients undergoing laparoscopic colorectal cancer surgery,a composite insulation intervention during the perioperative period can maintain body temperature,reduce postoperative stress,and significantly reduce the incidence of hypothermia and related complications. 展开更多
关键词 Laparoscopic surgery Composite insulation scheme Colorectal cancer Elderly patients Perioperative care Hypothermia prevention
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A Laboratorial Testing Scheme for 5G System:Channel Model Principle and Field Experiment Validation
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作者 Zhang Yuxiang Zhang Jianhua +7 位作者 Kang Yanan Zhao Mengxuan Qi Pan Zhang Zhen Tang Pan Tian Lei Liu Guangyi Yao Yuan 《China Communications》 2025年第9期113-128,共16页
As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple ... As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations. 展开更多
关键词 channel model field experiment high-speed dynamic time-varying(HDT) multiple-cell-multiple-user-multiple-input-multiple-output(MC-MU-MIMO) testing scheme the fifth generation communication(5G)
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Two-Dimensional Nonlinear Reaction Diffusion Equation with Time Efficient Scheme
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作者 Shahid Hasnain Muhammad Saqib Daoud Suleiman Mashat 《American Journal of Computational Mathematics》 2017年第2期183-194,共12页
This research paper represents a numerical approximation to non-linear two-dimensional reaction diffusion equation from population genetics. Since various initial and boundary value problems exist in two-dimensional r... This research paper represents a numerical approximation to non-linear two-dimensional reaction diffusion equation from population genetics. Since various initial and boundary value problems exist in two-dimensional reaction-diffusion, phenomena are studied numerically by different numerical methods, here we use finite difference schemes to approximate the solution. Accuracy is studied in term of L2, L∞ and relative error norms by random selected grids along time levels for comparison with exact results. The test example demonstrates the accuracy, efficiency and versatility of the proposed schemes. It is shown that the numerical schemes give better solutions. Moreover, the schemes can be easily applied to a wide class of higher dimension nonlinear reaction diffusion equations with a little modification. 展开更多
关键词 Forward in TIME and CENTRE in Space (FTCS) Taylors Series CRANK Nicolson ALTERNATING Direction IMPLICIT (ADI) scheme
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Flow Dynamics in Restricted Geometries: A Mathematical Concept Based on Bloch NMR Flow Equation and Boubaker Polynomial Expansion Scheme 被引量:1
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作者 Omotayo Bamidele Awojoyogbe Oluwaseun Michael Dada +1 位作者 Karem Boubaker Omoniyi Adewale Adesola 《Journal of Applied Mathematics and Physics》 2013年第5期71-78,共8页
Computational techniques are invaluable to the continued success and development of Magnetic Resonance Imaging (MRI) and to its widespread applications. New processing methods are essential for addressing issues at ea... Computational techniques are invaluable to the continued success and development of Magnetic Resonance Imaging (MRI) and to its widespread applications. New processing methods are essential for addressing issues at each stage of MRI techniques. In this study, we present new sets of non-exponential generating functions representing the NMR transverse magnetizations and signals which are mathematically designed based on the theory and dynamics of the Bloch NMR flow equations. These signals are functions of many spinning nuclei of materials and can be used to obtain information observed in all flow systems. The Bloch NMR flow equations are solved using the Boubaker polynomial expansion scheme (BPES) and analytically connect most of the experimentally valuable NMR parameters in a simplified way for general analyses of magnetic resonance imaging with adiabatic condition. 展开更多
关键词 BLOCH NMR Flow Equations Boubaker POLYNOMIAL Expansion scheme (BPES) Magnetic Resonance Imaging (MRI) ADIABATIC Condition
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ADER-WAF Schemes for the Homogeneous One-Dimensional Shallow Water Equations
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作者 Pavlos Stampolidis Maria Ch. Gousidou-Koutita 《Applied Mathematics》 2025年第1期61-112,共52页
ADER-WAF methods were first introduced by researchers E.F. Toro and V.A. Titarev. The linear stability criterion for the model equation for the ADER-WAF schemes is CCFL≤1, where CCFLdenotes the Courant-Friedrichs-Lew... ADER-WAF methods were first introduced by researchers E.F. Toro and V.A. Titarev. The linear stability criterion for the model equation for the ADER-WAF schemes is CCFL≤1, where CCFLdenotes the Courant-Friedrichs-Lewy (CFL) coefficient. Toro and Titarev employed CCFL=0.95for their experiments. Nonetheless, we noted that the experiments conducted in this study with CCFL=0.95produced solutions exhibiting spurious oscillations, particularly in the high-order ADER-WAF schemes. The homogeneous one-dimensional (1D) non-linear Shallow Water Equations (SWEs) are the subject of these experiments, specifically the solution of the Riemann Problem (RP) associated with the SWEs. The investigation was conducted on four test problems to evaluate the ADER-WAF schemes of second, third, fourth, and fifth order of accuracy. Each test problem constitutes a RP characterized by different wave patterns in its solution. This research has two primary objectives. We begin by illustrating the procedure for implementing the ADER-WAF schemes for the SWEs, providing the required relations. Afterward, following comprehensive testing, we present the range for the CFL coefficient for each test that yields solutions with diminished or eliminated spurious oscillations. 展开更多
关键词 1D Shallow Water Equations ADER-WAF schemes Finite Volume schemes Riemann Problem
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Asynchronous deployment scheme and multibody modeling of a ring-truss mesh reflector antenna
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作者 Baiyan He Kangkang Li +3 位作者 Lijun Jia Rui Nie Yesen Fan Guobiao Wang 《Acta Mechanica Sinica》 2025年第5期190-206,共17页
Mesh reflector antennas are the mainstream of large space-borne antennas,and the stretching of the truss achieves their deployment.Currently,the truss is commonly designed to be a single degree of freedom(DOF)deployab... Mesh reflector antennas are the mainstream of large space-borne antennas,and the stretching of the truss achieves their deployment.Currently,the truss is commonly designed to be a single degree of freedom(DOF)deployable mechanism with synchronization constraints.However,each deployable unit’s drive distribution and resistance load are uneven,and the forced synchronization constraints lead to the flexible deformation of rods and difficulties in the deployment scheme design.This paper introduces an asynchronous deployment scheme with a multi-DOF closed-chain deployable truss.The DOF of the truss is calculated,and the kinematic and dynamic models are established,considering the truss’s and cable net’s real-time coupling.An integrated solving algorithm for implicit differential-algebraic equations is proposed to solve the dynamic models.A prototype of a six-unit antenna was fabricated,and the experiment was carried out.The dynamic performances in synchronous and asynchronous deployment schemes are analyzed,and the results show that the cable resistance and truss kinetic energy impact under the asynchronous deployment scheme are minor,and the antenna is more straightforward to deploy.The work provides a new asynchronous deployment scheme and a universal antenna modeling method for dynamic design and performance improvement. 展开更多
关键词 Mesh antenna Deployment dynamic Driving scheme Performance evaluation Numerical analysis
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Evolution of multi-cluster fracturing in high-density layered shale considering the effect of injection scheme
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作者 Xiao Yan Haitao Yu Peng Zhang 《Petroleum Science》 2025年第5期2109-2122,共14页
Shale oil reservoir is generally characterized by well-developed bedding planes,and multi-cluster fracturing is the most effective technique to achieve stable shale oil production.In this paper,a multi-cluster fractur... Shale oil reservoir is generally characterized by well-developed bedding planes,and multi-cluster fracturing is the most effective technique to achieve stable shale oil production.In this paper,a multi-cluster fracturing model for a horizontal well in shale with high-density bedding planes is established.The fracture morphology,fracture geometry,fracturing area and multiple fracture propagation mechanism are analyzed under simultaneous fracturing,sequential fracturing,and alternative fracturing.Results show that in the case of small cluster spacing and three clusters,the growth of the middle fracture is inhibited and develops along the bedding planes under both simultaneous fracturing and alternative fracturing.For sequential fracturing,the increase in the interval time between each fracturing advances the post fracturing fracture deflecting to the pre-existing fractures through the bedding planes.The reactivation of the bedding planes can promote the extension of the fracturing area.Increasing the injection rate and the number of clusters promotes the activation of bedding planes.However,it is preferable to reduce the number of clusters to obtain more main fractures.Compared with modified alternating fracturing and cyclic alternating fracturing,alternating shut-in fracturing creates more main fractures towards the direction of the maximum in-situ stress.The fracturing efficiency for high-density layered shale is ranked as simultaneous fracturing>alternative fracturing>sequential fracturing. 展开更多
关键词 Multi-cluster fracturing Bedding planes Fracture morphology Injection scheme Numerical simulation
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Detecting Ethereum Ponzi Scheme Based on Hybrid Sampling for Smart Contract
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作者 Yuanjun Qu Xiameng Si +1 位作者 Haiyan Kang Hanlin Zhou 《Computers, Materials & Continua》 2025年第2期3111-3130,共20页
With the widespread use of blockchain technology for smart contracts and decentralized applications on the Ethereum platform, the blockchain has become a cornerstone of trust in the modern financial system. However, i... With the widespread use of blockchain technology for smart contracts and decentralized applications on the Ethereum platform, the blockchain has become a cornerstone of trust in the modern financial system. However, its anonymity has provided new ways for Ponzi schemes to commit fraud, posing significant risks to investors. Current research still has some limitations, for example, Ponzi schemes are difficult to detect in the early stages of smart contract deployment, and data imbalance is not considered. In addition, there is room for improving the detection accuracy. To address the above issues, this paper proposes LT-SPSD (LSTM-Transformer smart Ponzi schemes detection), which is a Ponzi scheme detection method that combines Long Short-Term Memory (LSTM) and Transformer considering the time-series transaction information of smart contracts as well as the global information. Based on the verified smart contract addresses, account features, and code features are extracted to construct a feature dataset, and the SMOTE-Tomek algorithm is used to deal with the imbalanced data classification problem. By comparing our method with the other four typical detection methods in the experiment, the LT-SPSD method shows significant performance improvement in precision, recall, and F1-score. The results of the experiment confirm the efficacy of the model, which has some application value in Ethereum Ponzi scheme smart contract detection. 展开更多
关键词 Blockchain smart contract detection Ponzi scheme long short-term memory hybrid sampling
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Sensitivity of a Kilometer-Scale Variable-Resolution Global Nonhydrostatic Model to Microphysics Schemes in Simulating a Mesoscale Convective System
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作者 Yihui ZHOU Rucong YU +2 位作者 Yi ZHANG Jian LI Haoming CHEN 《Advances in Atmospheric Sciences》 2025年第7期1333-1348,共16页
Accurately simulating mesoscale convective systems(MCSs)is essential for predicting global precipitation patterns and extreme weather events.Despite the ability of advanced models to reproduce MCS climate statistics,c... Accurately simulating mesoscale convective systems(MCSs)is essential for predicting global precipitation patterns and extreme weather events.Despite the ability of advanced models to reproduce MCS climate statistics,capturing extreme storm cases over complex terrain remains challenging.This study utilizes the Global–Regional Integrated Forecast System(GRIST)with variable resolution to simulate an eastward-propagating MCS event.The impact of three microphysics schemes,including two single-moment schemes(WSM6,Lin)and one double-moment scheme(Morrison),on the model sensitivity of MCS precipitation simulations is investigated.The results demonstrate that while all the schemes capture the spatial distribution and temporal variation of MCS precipitation,the Morrison scheme alleviates overestimated precipitation compared to the Lin and WSM6 schemes.The ascending motion gradually becomes weaker in the Morrison scheme during the MCS movement process.Compared to the runs with convection parameterization,the explicit-convection setup at 3.5-km resolution reduces disparities in atmospheric dynamics due to microphysics sensitivity in terms of vertical motions and horizontal kinetic energy at the high-wavenumber regimes.The explicit-convection setup more accurately captures the propagation of both main and secondary precipitation centers during the MCS development,diminishing the differences in both precipitation intensity and propagation features between the Morrison and two single-moment schemes.These findings underscore the importance of microphysics schemes for global nonhydrostatic modeling at the kilometer scale.The role of explicit convection for reducing model uncertainty is also outlined. 展开更多
关键词 variable-resolution modeling global nonhydrostatic model microphysics scheme mesoscale convective system explicit convection
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A Precipitation Classification Scheme for China with Special Consideration of Extreme Events
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作者 MA Ya-yu WANG Jing-song +5 位作者 ZHAO Liang LI Wen-juan YANG Hao WEN Wu ZHOU Hang CHEN Min 《Journal of Tropical Meteorology》 2025年第5期497-510,共14页
Due to global warming, extreme weather and climate events are becoming more frequent, highlighting the need to explore the changing characteristics of precipitation in China, including extreme precipitation. A cluster... Due to global warming, extreme weather and climate events are becoming more frequent, highlighting the need to explore the changing characteristics of precipitation in China, including extreme precipitation. A clustering algorithm was developed to classify summer(June, July, and August) daily precipitation in China from 1961 to 2020, considering spatial distribution, standard deviations, and frequency of extreme precipitation events. The results reveal six distinct precipitation climate zones, a classification that differs from previous divisions. While overall precipitation has decreased in most regions, the frequency of extreme precipitation events has increased across all clusters, indicating a shift in precipitation distribution patterns. Analysis shows that the weakened Lake Baikal blocking high and strengthened Mongolian cyclone influence the arid region in northwest China(Cluster 1), which is characterized by the lowest precipitation.The transition zone between the monsoon and arid region(Cluster 2) is affected by the Mongolian cyclone, water vapor transport from the Indian Ocean, and shifts in the monsoon boundary. Clusters 3 and 4 represent areas associated with advancement and retreat of the summer monsoon. In the Meiyu region, two distinct subregions have been identified exist.Cluster 4 is primarily influenced by the East Asia-Pacific wave train. Despite sharing similar climate drivers and proximity,Clusters 4 and 5 differ significantly due to topographic variations and disparate levels of urbanization. Cluster 5 exhibits a higher average precipitation, greater variability, and more frequent extreme events. Cluster 6 exhibits the highest overall precipitation in the coastal areas of Guangdong and Guangxi, where abundant water vapor contributes to a higher frequency of extreme precipitation. In addition, anthropogenic activities and urbanization significantly influence precipitation in Beijing-Tianjin-Hebei and Yangtze River Delta regions. This research proposes a precipitation classification scheme integrating multiple precipitation parameters, providing support for risk management and mitigation strategies in the face of increasing extreme precipitation events. 展开更多
关键词 precipitation characteristics extreme precipitation K-means clustering algorithm precipitation classification scheme risk management
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Microwave-assisted preparation of Z scheme heterojunction by anchoring ZnFe_(2)O_(4)on tubular-like g-C_(3)N_(4)for peroxymonosulfate activation towards levofloxacin degradation
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作者 HAN Peng-da DONG Guo-hua +6 位作者 ZHANG Xin-jia CHAI Dong-feng SU Ting ZHANG Zhuan-fang ZHAO Ming LI Jin-long ZHANG Wen-zhi 《Journal of Central South University》 2025年第3期894-918,共25页
It is still challenging for exploring high-active photocatalysts to efficiently remove levofloxacin(LFX)by activating peroxymonosulfate(PMS).Herein,we constructed a novel Z scheme ZnFe_(2)O_(4)/g-C_(3)N_(4)/CQDs(ZCC)h... It is still challenging for exploring high-active photocatalysts to efficiently remove levofloxacin(LFX)by activating peroxymonosulfate(PMS).Herein,we constructed a novel Z scheme ZnFe_(2)O_(4)/g-C_(3)N_(4)/CQDs(ZCC)heterojunction by anchoring ZnFe_(2)O_(4)on tubular-like g-C_(3)N_(4)induced by CQDs(denoted as CNC)using microwave-assisted thermal methods.The ZCC exhibits the highest photocatalytic activity in activating PMS for LFX degradation,endowing a removal rate~95.3%,which is 4.8 and 7.3 times that of pure ZnFe_(2)O_(4)(19.8%)and g-C_(3)N_(4)(13.1%),separately.The enhanced photocatalytic activity of ZCC can be attributed to the distinctive morphology of CNC,enhanced light response,increased specific surface area and abundant pore structure.Besides,the formed Z scheme heterojunction and CQDs acting as a transmission bridge of the photogenerated charges(e−and h+)can accelerate transfer and inhibit recombination of e−and h+.Radical capture experiments and electron spin resonance(ESR)measurements revealed that SO4•-and O2•-play a predominant role in degradation process of LFX.Liquid chromatography-mass spectrometry(LC-MS)was applied to identify intermediates and propose feasible degradation pathways of LFX.In conclusion,this study presents a promising strategy for regulating the photocatalytic activity of g-C_(3)N_(4)by simultaneously integrating CQDs induction and Z scheme heterojunction construction. 展开更多
关键词 ZnFe_(2)O_(4) carbon quantum dots g-C_(3)N_(4) LEVOFLOXACIN Z scheme heterojunction
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Compact finite difference schemes for the backward fractional Feynman–Kac equation with fractional substantial derivative
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作者 Jiahui Hu Jungang Wang +1 位作者 Yufeng Nie Yanwei Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期226-236,共11页
The fractional Feynman-Kac equations describe the distributions of functionals of non-Brownian motion, or anomalous diffusion, including two types called the forward and backward fractional Feynman-Kac equations, wher... The fractional Feynman-Kac equations describe the distributions of functionals of non-Brownian motion, or anomalous diffusion, including two types called the forward and backward fractional Feynman-Kac equations, where the nonlocal time-space coupled fractional substantial derivative is involved. This paper focuses on the more widely used backward version. Based on the newly proposed approximation operators for fractional substantial derivative, we establish compact finite difference schemes for the backward fractional Feynman-Kac equation. The proposed difference schemes have the q-th(q = 1, 2, 3, 4) order accuracy in temporal direction and fourth order accuracy in spatial direction, respectively. The numerical stability and convergence in the maximum norm are proved for the first order time discretization scheme by the discrete energy method, where an inner product in complex space is introduced. Finally, extensive numerical experiments are carried out to verify the availability and superiority of the algorithms. Also, simulations of the backward fractional Feynman-Kac equation with Dirac delta function as the initial condition are performed to further confirm the effectiveness of the proposed methods. 展开更多
关键词 BACKWARD FRACTIONAL Feynman-Kac EQUATION FRACTIONAL substantial DERIVATIVE compact finite difference scheme numerical inversion of LAPLACE transforms
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Central Upwind Scheme for Solving Multivariate Cell Population Balance Models
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作者 Shahzadi Mubeen ur Rehman Nadia Kiran Shamsul Qamar 《Applied Mathematics》 2014年第8期1187-1201,共15页
Microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins and other constituents. Because of the included level of details, multi-var... Microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins and other constituents. Because of the included level of details, multi-variable cell population balance models (PBMs) offer the most general way to describe the complicated phenomena associated with cell growth, substrate consumption and product formation. For that reason, solving and understanding of such models are essential to predict and control cell growth in the processes of biotechnological interest. Such models typically consist of a partial integro-differential equation for describing cell growth and an ordinary integro-differential equation for representing substrate consumption. However, the involved mathematical complexities make their numerical solutions challenging for the given numerical scheme. In this article, the central upwind scheme is applied to solve the single-variate and bivariate cell population balance models considering equal and unequal partitioning of cellular materials. The validity of the developed algorithms is verified through several case studies. It was found that the suggested scheme is more reliable and effective. 展开更多
关键词 CELL Population BALANCE CELL Growth Substrate CONSUMPTION CENTRAL UPWIND scheme Equal and Unequal Partitioning of Cells
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