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不含3-圈和4-圈的IC-平面图的均匀染色问题
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作者 黄丹君 吴弦禧 《浙江师范大学学报(自然科学版)》 2026年第1期26-32,共7页
图G的均匀k-染色是图G的一个正常k-点染色,且满足对任意i,j∈{1,2,…,k},有||V_(i)|-|V_(j)||≤1,其中V_(i)(1≤i≤k)表示染颜色i的顶点集.基于已有的研究结果,研究了不含3-圈和4-圈的IC-平面图,运用反证法证明得到了:Δ(G)≥7且不含3-... 图G的均匀k-染色是图G的一个正常k-点染色,且满足对任意i,j∈{1,2,…,k},有||V_(i)|-|V_(j)||≤1,其中V_(i)(1≤i≤k)表示染颜色i的顶点集.基于已有的研究结果,研究了不含3-圈和4-圈的IC-平面图,运用反证法证明得到了:Δ(G)≥7且不含3-圈和4-圈的IC-平面图是均匀Δ(G)-可染的,其中Δ(G)是图G的最大度. 展开更多
关键词 均匀染色 ic-平面图 最大度
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Prediction of microstructure evolution of ZK61 alloy during hot spinning by internal state variable model 被引量:2
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作者 Jin-qi PAN Wen-cong ZHANG +3 位作者 Jian-lei YANG Song-hui WANG Yong WU Huan LI 《Transactions of Nonferrous Metals Society of China》 2025年第1期126-142,共17页
An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of t... An internal state variable(ISV)model was established according to the experimental results of hot plane strain compression(PSC)to predict the microstructure evolution during hot spinning of ZK61 alloy.The effects of the internal variables were considered in this ISV model,and the parameters were optimized by genetic algorithm.After validation,the ISV model was used to simulate the evolution of grain size(GS)and dynamic recrystallization(DRX)fraction during hot spinning via Abaqus and its subroutine Vumat.By comparing the simulated results with the experimental results,the application of the ISV model was proven to be reliable.Meanwhile,the strength of the thin-walled spun ZK61 tube increased from 303 to 334 MPa due to grain refinement by DRX and texture strengthening.Besides,some ultrafine grains(0.5μm)that played an important role in mechanical properties were formed due to the proliferation,movement,and entanglement of dislocations during the spinning process. 展开更多
关键词 internal state variable model hot spinning ZK61 alloy finite element simulation texture evolution
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A new radioactive microsphere:Y-90 carbon microsphere for selective internal radiation therapy of advanced liver cancer 被引量:1
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作者 Xiaosheng Zhao Jie Gao +13 位作者 Kun Shi Chixiang Zhang Wenliang Ma Guo Lyu Jun Zhang Jing Lu Qiangqiang Liu Xianjin Luo Kunru Yu Jianguo Li Qiang Ge Jiming Cai Chang Liu Zhiyong Qian 《Chinese Chemical Letters》 2025年第8期360-365,共6页
Radioactive microspheres have demonstrated excellent therapeutic effects and good tolerance in the treatment of unresectable primary and secondary liver malignancies.This is attributed to precise embolization and pote... Radioactive microspheres have demonstrated excellent therapeutic effects and good tolerance in the treatment of unresectable primary and secondary liver malignancies.This is attributed to precise embolization and potent anti-tumor effect.However,certain limitations such as unstable loading,perfusion stasis,heterogeneous distribution,ectopic distribution,and insufficient dosage,restrict their clinical application.Herein,a novel personalized Y-90 carbon microsphere with high uniformity,high specific activity and high availability(^(90)Y-HUACM)is presented.It is synthesized through planar molecular complex adsorption and chemical deposition solidification.^(90)Y-HUACM exhibited controllable size,excellent biocompatibility,outstanding in vitro and in vivo stability.The radiolabeling efficiency of Y-90 exceeded 99%and the leaching rate of Y-90 is far below 0.1%.Furthermore,the excellent anti-tumor effect,nuclide loading stability,anti-reflux characteristics,precise embolization,and biosafety of^(90)Y-HUACM were validated in a rabbit VX2liver tumor model.In summary,this new,high-performance,and customizable radioactive microsphere provides a superior choice for selective internal radiation treatment of advanced liver cancer is expected to be rapidly applied in clinical practice. 展开更多
关键词 Carbon microsphere Yttrium-90 Selective internal radiation therapy Livercancer RADIOACTIVE
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ICF理念框架下精准化康复训练在儿童脑性瘫痪痉挛型偏瘫中的应用
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作者 李家妮 张玉琼 +3 位作者 邓桂珠 柏亚平 钟粮蔚 李晓乐 《海南医学》 2026年第2期263-268,共6页
目的探讨运用国际功能、残疾和健康分类(ICF)理念框架下精准化康复训练对儿童脑性瘫痪(CP)痉挛型偏瘫中的应用效果。方法选择东莞市妇幼保健院2020年6月至2023年12月收治的80例CP痉挛型偏瘫患儿,依据随机数字表法将其分为观察组与对照组... 目的探讨运用国际功能、残疾和健康分类(ICF)理念框架下精准化康复训练对儿童脑性瘫痪(CP)痉挛型偏瘫中的应用效果。方法选择东莞市妇幼保健院2020年6月至2023年12月收治的80例CP痉挛型偏瘫患儿,依据随机数字表法将其分为观察组与对照组,各40例。对照组在常规治疗基础上予以常规康复训练,观察组在对照组基础上予以ICF理念框架下精准化康复训练方案。比较两组患儿治疗后6个月的临床疗效、脑瘫儿手功能分级系统(MACS)Ⅰ级率、粗大运动评估88项(GMFM-88)评分、改良Ashworth痉挛评定量表(MAS)Ⅰ级率、0~6岁神经心理发育量表(DST)的发育商(DQ)值。结果治疗后6个月,观察组患儿总有效率为90.00%,明显高于对照组的70.00%,差异有统计学意义(P<0.05);治疗后6个月,两组患儿MACSⅠ级率、GMFM-88、MASⅠ级率及DST评分DQ值均上升,观察组患儿MACSⅠ级率、GMFM-88、MASⅠ级率及DST评分DQ值分别为55.00%、(78.24±3.17)分、72.50%、(78.45±3.90)分,明显高于对照组的30.00%、(73.10±4.63)分、27.50%、(75.18±4.77)分,差异均有统计学意义(P<0.05)。结论运用ICF理念框架下精准化康复训练方案在CP痉挛型偏瘫患儿中的效果显著,可有效改善患儿瘫侧肢体运动功能,提升智力水平。 展开更多
关键词 国际功能、残疾和健康分类 康复训练 儿童 脑性瘫痪痉挛型偏瘫 运动功能 智力
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Application of Sr_(2)FeMoO_(6−δ)-based medium entropy oxide as an anode internal reforming catalyst in solid oxide fuel cells fueled by low -concentration coal mine methane 被引量:1
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作者 Chuanqi Sun Jinke Zhang +7 位作者 Xiuyang Qian Mingfei Li Hongming Liu Jiangbo Dong Jinda Li Wenlin Yang Mumin Rao Yihan Ling 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2650-2658,共9页
Low-concentration coal mine methane(LC-CMM),which is predominantly composed of methane,serves as a clean and low-carbon energy resource with significant potential for utilization.Utilizing LC-CMM as fuel for solid oxi... Low-concentration coal mine methane(LC-CMM),which is predominantly composed of methane,serves as a clean and low-carbon energy resource with significant potential for utilization.Utilizing LC-CMM as fuel for solid oxide fuel cells(SOFCs)represents an efficient and promising strategy for its effective utilization.However,direct application in Ni-based anodes induces carbon deposition,which severely degrades cell performance.Herein,a medium-entropy oxide Sr_(2)FeNi_(0.1)Cr_(0.3)Mn_(0.3)Mo_(0.3)O_(6−δ)(SFNCMM)was developed as an anode internal reforming catalyst.Following reduction treatment,FeNi_(3) nano-alloy particles precipitate on the surface of the material,thereby significantly enhancing its catalytic activity for LC-CMM reforming process.The catalyst achieved a methane conversion rate of 53.3%,demonstrating excellent catalytic performance.Electrochemical evaluations revealed that SFNCMM-Gd_(0.1)Ce_(0.9)O_(2−δ)(GDC)with a weight ratio of 7:3 exhibited superior electrochemical performance when employed as the anodic catalytic layer.With H_(2) and LC-CMM as fuels,the single cell achieved maximum power densities of 1467.32 and 1116.97 mW·cm^(−2) at 800℃,respectively,with corresponding polarization impedances of 0.17 and 1.35Ω·cm^(2).Furthermore,the single cell maintained stable operation for over 100 h under LC-CMM fueling without significant carbon deposition,confirming its robust resistance to carbon formation.These results underscore the potential of medium-entropy oxides as highly effective catalytic layers for mitigating carbon deposition in SOFCs. 展开更多
关键词 solid oxide fuel cell medium entropy oxide low-concentration coal mine methane anode internal reforming catalyst electro-chemical performance
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Nonlinear Dynamic Modeling of Steel Catenary Risers with Varying Curvatures Under Internal Flow and External Current Excitation 被引量:1
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作者 LI Fang-qiu CHENG Hao +4 位作者 LIU Miao-er LI Xin-xin AN Chen LU Hai-long LU Zhao-kuan 《China Ocean Engineering》 2025年第5期904-916,共13页
As oil and gas exploration moves into deeper waters,marine risers are subjected to increasingly complex service conditions,including vessel motions,ocean currents,seabed-soil interactions,and internal flow effects.Thi... As oil and gas exploration moves into deeper waters,marine risers are subjected to increasingly complex service conditions,including vessel motions,ocean currents,seabed-soil interactions,and internal flow effects.This work establishes a dynamic behavior model of steel catenary risers(SCRs)with varying curvatures subjected to internal flow and external currents and considers the effects of pipe-soil interactions on the curvature profile.The governing equation is solved via the generalized integral transform technique(GITT),which yields a semi-analytical solution of a high-order nonlinear partial differential equation.Parametric studies are then performed to analyze the effects of varying curvature on the vibration frequency and amplitude of SCRs.The vibration frequency and amplitude increase with the touchdown angle and hang-off angle,although the effect of the hang-off angle is negligible.Additionally,as the curvature increases along the centerline axis,the position of the maximum amplitude of the SCR moves upward. 展开更多
关键词 steel catenary riser(SCR) CURVATURE generalized integral transform technique(GITT) dynamic behav-ior internal flow and external current
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Discussion on“Data-driven Methods to Predict the Burst Strength of Corroded Line Pipelines Subjected to Internal Pressure https://doi.org/10.1007/s11804-022-00263-0”
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作者 Mojtaba Mokhtari Robert E.Melchers 《哈尔滨工程大学学报(英文版)》 2025年第1期249-251,共3页
The authors(Cai et al.,2022)claim that their proposed machine learning(ML)models,which are based on three typical ML algorithms and are trained to predict the burst capacity of pitting corroded pipelines,perform bette... The authors(Cai et al.,2022)claim that their proposed machine learning(ML)models,which are based on three typical ML algorithms and are trained to predict the burst capacity of pitting corroded pipelines,perform better than the existing semi-empirical formulas recommended by the international engineering code developers,DNV and ASME.The authors’assessments of the semi-empiri‐cal burst capacity formulas in Figure 10(a)and Table 8(Cai et al.,2022)incorrectly indicate that DNVGL-RP F101,ASME B31G,and modified ASME B31G are dan‐gerously unsafe due to significantly overestimating burst pressures in several cases.In contrast to the results and conclusions in Cai et al. 展开更多
关键词 internal FIGURE ASME
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Observation on the Effect of Internal Limiting Membrane Flipping and Covering Technique in the Treatment of High Myopic Macular Hole
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作者 Zhiwei Li 《Journal of Clinical and Nursing Research》 2025年第5期245-251,共7页
Objective:To evaluate the effectiveness of the internal limiting membrane(ILM)flipping and covering technique in the treatment of patients with high myopic macular hole(HMMH).Methods:One hundred and two patients with ... Objective:To evaluate the effectiveness of the internal limiting membrane(ILM)flipping and covering technique in the treatment of patients with high myopic macular hole(HMMH).Methods:One hundred and two patients with HMMH who were admitted to the hospital from June 2019 to June 2024 were selected.The minimum diameter of the macular hole(MH)in all patients was≤500μm.The patients were randomly divided into two groups.The experimental group received 25G pars plana vitrectomy(PPV)combined with ILM flipping and covering technique,while the reference group received PPV combined with ILM peeling.The efficacy indicators and best corrected visual acuity levels were compared between the two groups.Results:The MH closure rate and retinal reattachment rate were higher in the experimental group than in the reference group at 3 and 6 months postoperatively(P<0.05).The best corrected visual acuity level was higher in the experimental group than in the reference group at 3 and 6 months postoperatively(P<0.05).The Chinese version of the Visual Function-Related Quality of Life Questionnaire-25(CVRQOL-25)score was higher in the experimental group than in the reference group at 3 and 6 months postoperatively(P<0.05).No serious complications were observed in both groups postoperatively,and there was no difference between the two groups(P>0.05).Conclusion:The ILM flipping and covering technique can improve the MH closure rate and retinal reattachment rate in patients with HMMH(diameter≤500μm),enhance the best corrected visual acuity level,and improve the quality of life related to visual function,with fewer postoperative complications. 展开更多
关键词 internal limiting membrane flipping internal limiting membrane peeling High myopic macular hole
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All solid-solution S-scheme heterojunction with adjustable internal electric field for highly efficient photocatalytic activity
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作者 Shiya Yue Rong Li +3 位作者 Zhengrong Wei Yun Gao Karen Wilson Xuxing Chen 《Chinese Journal of Catalysis》 2025年第4期353-362,共10页
Developing an efficient photocatalyst is the key to realize the practical application of photocatalysis.The S-scheme heterojunction has great potential in photocatalysis due to its unique charge-carrier migration path... Developing an efficient photocatalyst is the key to realize the practical application of photocatalysis.The S-scheme heterojunction has great potential in photocatalysis due to its unique charge-carrier migration pathway,effective light absorption and high redox capacity.However,further enhancing the built-in electric field of the S-scheme,accelerating carrier separation,and achieving higher photocatalytic performance remain unresolved challenges.Herein,based on the continuously adjustable band structure of continuous solid-solution,a novel 0D/2D all solid-solution S-scheme heterojunction with adjustable internal electric field was designed and fabricated by employing a solid-solution of ZnxCd_(1–x)S and Bi_(2)MoyW_(1–y)O_(6)respectively as reduction and oxidation semiconductors.The synergistic optimization of effective light absorption,fast photogenerated carrier separation,and high redox potential leads can be tuned to promote photocatalytic activity.Under visible light,the S-scheme system constructed by Zn_(0.4)Cd_(0.6)S quantum dot(QDs)and Bi_(2)Mo_(0.2)W_(0.8)O_(6)monolayer exhibits a high rate for photocatalytic degradation C_(2)H_(4)(150.6×10^(–3)min^(–1)),which is 16.5 times higher than that of pure Zn_(0.4)Cd_(0.6)S(9.1×10^(–3)min^(–1))and 53.8 times higher than pure Bi_(2)Mo_(0.2)W_(0.8)O_(6)(2.8×10^(–3)min^(–1)).Due to the unique charge-carrier migration pathway,photo-corrosion of Zn_(x)Cd_(1–x)S is further inhibited simultaneously.In-situ irradiation X-ray photoelectron spectroscopy,photoluminescence spectroscopy,time-resolved photoluminescence,transient absorption spectroscopy and electron paramagnetic resonance provide compelling evidence for interfacial charge transfer via S-scheme pathways,while in-situ diffuse reflectance infrared Fourier transform spectroscopy identifies the reaction pathway for C_(2)H_(4)degradation.This novel S-scheme photocatalysts demonstrates excellent performance and potential for the practical application of the fruits and vegetables preservation at room temperatures. 展开更多
关键词 Photocatalysis S-scheme SOLID-SOLUTION internal electric field Ethylene
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Pd-Catalyzed highly regioselective migratory hydroesterification of internal olefins with formates
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作者 Junhua Li Tianci Shen +2 位作者 Yahui Zhuang Yu Fu Yian Shi 《Chinese Chemical Letters》 2025年第7期371-375,共5页
Double bonds of internal olefins can be efficiently migrated to the terminal carbons and regioselectively hydroesterified with formates in the presence of Pd(OAc)_(2) and 1,2-DTBPMB under mild reaction conditions,prov... Double bonds of internal olefins can be efficiently migrated to the terminal carbons and regioselectively hydroesterified with formates in the presence of Pd(OAc)_(2) and 1,2-DTBPMB under mild reaction conditions,providing a wide variety of corresponding linear carboxylic esters bearing various functional groups in good yields and>20:1 linear/branch ratios.The reaction is optionally simple and does not need to use CO gas and acid co-catalysts. 展开更多
关键词 PD-CATALYZED Migratory hydroesterification internal olefins Olefin isomerization FORMATES
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Dynamics and energetics of semidiurnal internal tides in the Weddell-Scotia Confluence
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作者 Wenjia Min Qun Li +4 位作者 Zhiliang Liu Bo Zhao Yue Ma Hang Chang Weidong Wang 《Acta Oceanologica Sinica》 2025年第3期117-129,共13页
We use a high-resolution numerical simulation to analyze the generation and evolution of semidiurnal internal tides in the Weddell-Scotia Confluence.Our results indicate that two ridges near the Antarctic Peninsula,th... We use a high-resolution numerical simulation to analyze the generation and evolution of semidiurnal internal tides in the Weddell-Scotia Confluence.Our results indicate that two ridges near the Antarctic Peninsula,the South Scotia Ridge(SSR)and the Philip Ridge(PR),are energetic sources of semidiurnal internal tides.The strongest semidiurnal barotropic to baroclinic energy conversion occurs around the crest of the SSR,reaching 0.3 W/m^(2).The depthintegrated,tidally averaged semidiurnal internal tide energy fluxes that radiated from the SSR reach about 2 kW/m.The northward semidiurnal internal tide energy fluxes entering the Scotia Sea are stronger than the southward energy fluxes entering the Powell Basin.For the SSR region between the South Orkney Plateau and Elephant Island,the areaintegrated barotropic to baroclinic conversion rate is 0.71 GW,of which 0.56 GW(79%)dissipates locally.The dissipation of internal tides occurs mainly in water depths of less than 1000 m.The dissipation rate over the SSR is as high as 10−7 W/kg.The energy fluxes create an anticlockwise gyre between the SSR and PR.The horizontal kinetic energy and available potential energy oscillate sinusoidally with peaks occurring at quarter-wavelength intervals.This energy pattern suggests the formation of standing waves due to interference between the semidiurnal internal tides originating from the SSR and PR.The results of this study show that internal tides and related mixing need to be considered in the analysis of water mass transformation in the Southern Ocean. 展开更多
关键词 internal tides Weddell-Scotia Confluence standing waves MITgcm
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Spatiotemporal Dynamics of Internal Migration in Burkina Faso
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作者 Gansaonré Raogo Noël Dahani Dramane 《Journal of Environmental & Earth Sciences》 2025年第2期31-48,共18页
Migration is a complex demographic phenomenon.Its dynamics can be explained by several factors whose spatial and temporal evolution is not easy to control.That is why this article aims to understand the factors of mig... Migration is a complex demographic phenomenon.Its dynamics can be explained by several factors whose spatial and temporal evolution is not easy to control.That is why this article aims to understand the factors of migration from a spatiotemporal perspective to fill the gaps in the literature.The aim of this article is to analyse the spatiotemporal dynamics of internal migration factors to deduce the zones of origin and destination in Burkina Faso.To do this,several types of data were used.These included secondary,spatial,statistical and survey data.The results of this study show that the influence of internal migration factors is uneven.The spatial distribution of internal migration factors follows a north-south gradient,with favourable conditions in the south.In fact,the northern part is characterised by a large population exodus,with around 42.6%of outgoing internal migrants,and the southern part by a large population influx.This southern part of the country receives around 34.6%of internal migrants.The areas from which migrants depart have unfavourable climatic,environmental,or socio-economic conditions,whereas the areas to which migrants migrate are characterised by favourable conditions for these factors. 展开更多
关键词 Burkina Faso internal Migration FACTOR GIS Multi-Criteria Analysis
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Effects of internals on macroscopic fluid dynamics in a bubble column
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作者 Shijie Liu Jin Liang +4 位作者 Qin Li Hui Yu Haoliang Wang Xiangyang Li Chao Yang 《Chinese Journal of Chemical Engineering》 2025年第1期19-29,共11页
The effects of internals on liquid mixing and gas-liquid mass transfer have rarely been investigated in bubble columns,and the commonly used measurement method overestimates significantly overall gas holdup.Firstly,ga... The effects of internals on liquid mixing and gas-liquid mass transfer have rarely been investigated in bubble columns,and the commonly used measurement method overestimates significantly overall gas holdup.Firstly,gas holdup measurement method is improved by conducting multi-point liquid level measurement and using net fluid volume instead of bed volume to calculate gas holdup.Then,a stable conductivity method for liquid macromixing has been established by shielding large bubbles using#16nylon mesh.Subsequently,the influences of internal coverage(=12.6%,18.9% and 25.1%) on macroscopic fluid dynamics in a bubble column with a free wall area are systematically investigated.It is found that the presence of internals has a notable effect on macroscopic fluid dynamics.The overall gas holdup and gas-liquid volumetric mass transfer coefficient decrease,and the macromixing time decreases with the increase of internal cross-sectional area coverage.These are mainly caused by the uneven distribution of airflow due to the low resistance in the free wall area.This design makes maintenance easier,but in reality,the reactor performance has decreased.Further improvements will be made to the reactor performance based on such a configuration through flow guidance using baffles. 展开更多
关键词 Bubble column internalS Macroscopic fluid dynamics MIXING Mass transfer
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Energetics of Internal Tides and Lee Waves Under Different Background Flow Intensities
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作者 JIANG Zenghao CHEN Xu +1 位作者 MENG Jing CAO Anzhou 《Journal of Ocean University of China》 2025年第2期259-268,共10页
Ocean mixing is a consequence of essential dynamic processes such as internal tides and lee waves that occur near the seafloor topography.Internal tides and lee waves are generated by barotropic tidal currents and geo... Ocean mixing is a consequence of essential dynamic processes such as internal tides and lee waves that occur near the seafloor topography.Internal tides and lee waves are generated by barotropic tidal currents and geostrophic flows,respectively.Ocean current is composed of multiple flows;thus,internal tides and lee waves occur concurrently in the real ocean.In this paper,the Massachusetts Institute of Technology general circulation model(MITgcm)is used to conduct 2D numerical experiments.By varying background flow intensities,the energy and dissipation relationship between internal tides and lee waves are investigated.The results reveal that the internal tide beams become asymmetric due to the influence of Doppler shift.The lee wave structure gradually leads the wave field when the background flow velocity rises constantly.The presence of a background flow increases the energy portion of the high-mode wave by up to 15%-20%.Moreover,strong shear,owing to the background flow,considerably increases dissipation.When the background flow velocity is higher than the barotropic tidal current velocity,the isopycnal overturn triggered by the lee wave generates a dissipation of the same order of magnitude as the shear. 展开更多
关键词 internal tides lee waves ENERGETicS turbulent dissipation rate
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A new paradigm of internal wave in the Arctic Ocean
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作者 LI Qun 《Advances in Polar Science》 2025年第1期1-4,共4页
In the Arctic Ocean,turbulent mixing drives vertical heat flux,thereby affecting the sea ice variability.Internal wave is regarded as one of the important energy sources of mixing in this region.The high latitude and ... In the Arctic Ocean,turbulent mixing drives vertical heat flux,thereby affecting the sea ice variability.Internal wave is regarded as one of the important energy sources of mixing in this region.The high latitude and sea ice cover make internal wave in the Arctic Ocean apparently differs from that in mid-and low-latitude oceans.However,the internal wave and its underlying mechanism are less understood due to the lack of observations.This paper briefly reviews the recent studies and unresolved questions on the internal wave in the Arctic Ocean,including wind-driven near-inertial wave,internal tide,and high-frequency internal wave.The aim is to provide new insights for in-depth research in the future,with a focus on the mechanisms responsible for the evolution of internal wave under the rapidly changing Arctic climate. 展开更多
关键词 internal wave turbulent mixing Arctic Ocean sea ice TIDE
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An optimal control method of internal resonances for vibration isolation system using an aperiodic isolator
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作者 Yujun Liu Jing Liu +2 位作者 Guang Pan Qiaogao Huang Baowei Song 《Acta Mechanica Sinica》 2025年第1期175-191,共17页
Periodic isolator is well known for its wave filtering characteristic.While in middle and high frequencies,the internal resonances of the periodic isolator are evident especially when damping is small.This study propo... Periodic isolator is well known for its wave filtering characteristic.While in middle and high frequencies,the internal resonances of the periodic isolator are evident especially when damping is small.This study proposes a novel aperiodic vibration isolation for improving the internal resonances control of the periodic isolator.The mechanism of the internal resonances control by the aperiodic isolator is firstly explained.For comparing the internal resonances suppression effect of the aperiodic isolator with the periodic isolator,a dynamic model combing the rigid machine,the isolator,and the flexible plate is derived through multi subsystem modeling method and transfer matrix method,whose accuracy is verified through the finite element method.The influences of the aperiodicity and damping of the isolator on the vibration isolation performance and internal resonances suppression effect are investigated by numerical analysis.The numerical results demonstrate that vibration attenuation performances of the periodic isolator and aperiodic isolator are greatly over than that of the continuous isolator in middle and high frequencies.The aperiodic isolator opens the stop bandgaps comparing with the periodic isolator where the pass bandgaps are periodically existed.The damping of the isolator has the stop bandgap widening effect on both the periodic isolator and the aperiodic isolator.In addition,a parameter optimization algorithm of the aperiodic isolator is presented for improving the internal resonances control effect.It is shown that the vibration peaks within the target frequency band of the aperiodic isolator are effectively reduced after the optimization.Finally,the experiments of the three different vibration isolation systems are conducted for verifying the analysis work. 展开更多
关键词 internal resonances Vibration isolation Periodic structure Vibration wave propagation
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Internal surface finishing and roughness measurement:A critical review
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作者 Jiang GUO Qikai LI +5 位作者 Pu QIN Ankang YUAN Mingyang LU Xiaolong KE Yicha ZHANG Benny CFCHEUNG 《Chinese Journal of Aeronautics》 2025年第8期563-587,共25页
Modern industrial equipment is increasingly characterized by miniaturization,integration,and high performance,necessitating the production of complex structural parts with exceptionally high internal surface quality.D... Modern industrial equipment is increasingly characterized by miniaturization,integration,and high performance,necessitating the production of complex structural parts with exceptionally high internal surface quality.Direct manufacturing often leads to high internal surface roughness,which traditional finishing and measuring methods cannot adequately address due to the decreasing size and increasing complexity of internal structures.This is especially true for components like pipes with large aspect ratios,extremely small deep holes,multi-stage bends,cross pipes,and array holes.To meet the high-performance manufacturing demands of these parts,advanced internal surface finishing and roughness measurement technologies have gained significant attention.This review focuses on the challenges and solutions related to internal surface parts with various apertures and complex structures.Internal surface finishing methods are categorized into mechanical finishing,fluid-based finishing,and energy-field-based finishing based on their characteristics.Roughness measurement technologies are divided into tool-probing and non-probing methods.The principles,required equipment,and key parameters of each finishing and measurement approach are discussed in detail.Additionally,the advantages and limitations of these methods are summarized,and future trends are forecasted.This paper serves as a comprehensive guide for researchers and engineers aiming to enhance the internal surface quality of complex structure parts. 展开更多
关键词 internal surface finishing Roughness measurement Small aperture Complex structure Tool-probing
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Clinical Efficacy of Different Internal Fixation Implants for Post-Traumatic Nonunion of Limb Fractures:A Comparative Study
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作者 Li He Cheng Weiqiang Zhu Dingguo 《Science International Innovative Medicine》 2025年第2期25-30,共6页
To compare the clinical efficacy of locking plate(LP)fixation and intramedullary nail(IMN)fixation for the treatment of post-traumatic nonunion of diaphyseal fractures of the femur and tibia.Methods:This single-center... To compare the clinical efficacy of locking plate(LP)fixation and intramedullary nail(IMN)fixation for the treatment of post-traumatic nonunion of diaphyseal fractures of the femur and tibia.Methods:This single-center retrospective comparative study included 50 adult patients with aseptic nonunion of femoral or tibial diaphyseal fractures treated at our institution between January 2015 and January 2025.Patients underwent either locking-plate(LP)fixation(n=25)or intramedullary nailing(IMN)(n=25).The primary outcome was radiographic union at 12 months postoperatively.Secondary outcomes included time to union,operative time,intraoperative blood loss,length of hospital stay,incidence of complications(superficial/deep infection,implant failure,malunion),and 12-month functional status assessed by the Lower Extremity Functional Scale(LEFS).Statistical comparisons used Welch t tests for continuous variables and χ^(2) or Fisher exact tests for categorical variables.The protocol received institutional review board approval with waiver of informed consent.Results:Among 50 patients(LP=25;IMN=25),the 12-month union rate was 88.00%(22/25)in the LP group and 96.00%(24/25)in the IMN group(p=0.609).Time to union was shorter with IMN(6.20±1.83 vs 7.51±2.12 months;p=0.023).Operative time(110.52±25.23 vs 145.81±30.21 min;p<0.01)and intraoperative blood loss(250.41±80.64 vs 350.22±95.30 ml;p<0.01)favored IMN.Length of hospital stay was similar(6.24±1.83 vs 6.82±2.11 days;p=0.284).The incidence of superficial wound infection did not differ significantly(12.00%vs 4.00%;p=0.609).Twelve-month LEFS scores were comparable(65.44±10.21 vs 67.10±9.83;p=0.451).Conclusion:Both locking plate and intramedullary nail fixation are effective in the treatment of femoral and tibial nonunion,with high rates of union and good functional outcomes.Intramedullary nailing may be associated with a shorter time to union,reduced operative time and blood loss,and a lower risk of superficial wound infection compared to locking plate fixation.The choice of implant should be individualized based on fracture characteristics,patient factors,and surgeon preference. 展开更多
关键词 NONUNION Limb Fractures internal Fixation Locking Plate Intramedullary Nail Clinical Efficacy
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Progress on oceanic sediment dynamic processes induced by nonlinear internal waves
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作者 Weihan Ruan Yanwei Zhang +2 位作者 Danni Lyu Liuzhenyi Zhang Zhiyuan Zhuang 《Acta Oceanologica Sinica》 2025年第1期59-71,共13页
Nonlinear internal waves(NLIWs)exhibit robust dynamic submesoscale motions,connecting large-scale tides to smallscale shear instabilities in the ocean.Previous studies have mainly focused on their generation mechanism... Nonlinear internal waves(NLIWs)exhibit robust dynamic submesoscale motions,connecting large-scale tides to smallscale shear instabilities in the ocean.Previous studies have mainly focused on their generation mechanisms and evolution along their paths.Considering their global distribution resulting from the primary origin in tide-topography interaction,there is an increasing cross-disciplinary interest in understanding how these energetic and ubiquitous NLIWs contribute to sediment redistribution in the ocean.This paper presents fundamental theories on NLIWs and comprehensively reviews triggering mechanisms,different types of instability,and sediment responses by summarizing recent theoretical parameterizations,numerical simulations,laboratory experiments,and in-situ observations.We specifically focus on elucidating various types of instability along with their impact on sediment dynamic processes.Finally,we outline several unresolved issues that require further exploration for a quantitative investigation into NLIWinduced sediment transfer in the ocean. 展开更多
关键词 nonlinear internal waves INSTABILITY sediment resuspension and transport in-situ observations
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Robotic approach for lymphadenectomy of internal mammary lymph nodes in breast cancer: Five case reports
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作者 Alessandro Pardolesi Michele Ferrari +7 位作者 Giovanni Leuzzi Alessia Stanzi Matteo Calderoni Clarissa Uslenghi Marco Scarci Federico Raveglia Ugo Cioffi Piergiorgio Solli 《World Journal of Clinical Oncology》 2025年第10期285-294,共10页
BACKGROUND Internal mammary(IM)lymphadenopathies in breast cancer indicate a worse prognosis than axillary metastases,yet they are rarely assessed.Accurate staging is essential for treatment planning.Robotic biopsy of... BACKGROUND Internal mammary(IM)lymphadenopathies in breast cancer indicate a worse prognosis than axillary metastases,yet they are rarely assessed.Accurate staging is essential for treatment planning.Robotic biopsy offers a promising alternative to video-assisted thoracic surgery for precise histological sampling.This article outlines a systematic robot-assisted dissection approach to enhance staging accuracy and optimize breast cancer management.CASE SUMMARY At our institution,robotic lymphadenectomy of the IM chain was performed in 5 patients between July 2020 and December 2024.Patients were positioned in a 30°semi-supine position with a roll under the shoulder to elevate the chest.The camera port was inserted in the fifth intercostal space along the mid-axillary line,allowing a 0°,12 mm robotic camera to inspect the chest cavity;CO_(2) insufflation(8 L/minute,8-10 mmHg)facilitated lung collapse and pneumo-mediastinum formation for improved dissection.Under direct vision,two additional operative ports were placed:One in the third intercostal space(anterior axillary line)and another in the fifth intercostal space(3-4 cm lateral to the parasternal line).The mean operative time was 118 minutes,with a median hospital stay of two days.No major complications occurred.Histology confirmed breast carcinoma metas tases in three patients,while two had benign disease.CONCLUSION Robotic biopsy of IM lymph nodes is safe,feasible,and provides key information on breast cancer management,with very rare contraindications. 展开更多
关键词 Breast cancer Lymph node internal mammary chain Robotic surgery Case report
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