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Ultrahigh-Mass-Loading Electrodes With Enhanced Homogeneity Using a High-Concentration Slurry for Lithium-Ion Batteries
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作者 Jun Kyu Park Woohyeon Shin +14 位作者 Woohyeon Jo Hyo-Jeong Lee Won-Yong Jeon Jinho Ahn Jihee Yoon Yea-Ji Jeong Joonyoung Oh Minji Kang Min-Jae Choi Jin Joo Jongsoon Kim Seong-Keun Cho Jun Dong Park Jaewook Nam Jung-Keun Yoo 《Carbon Energy》 2026年第1期126-137,共12页
Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity c... Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity carbon nanotubes(CNT)conductive materials,and electrode thickening.However,these methods are still limited due to the limitation in the capacity of high-nickel NCM,aggregation of CNT conductive materials,and nonuniform material distribution of thick-film electrodes,which ultimately damage the mechanical and electrical integrity of the electrode,leading to a decrease in electrochemical performance.Here,we present an integrated binder-CNT composite dispersion solution to realize a high-solids-content(>77 wt%)slurry for high-mass-loading electrodes and to mitigate the migration of binder and conductive additives.Indeed,the approach reduces solvent usage by approximately 30%and ensures uniform conductive additive-binder domain distribution during electrode manufacturing,resulting in improved coating quality and adhesive strength for high-mass-loading electrodes(>12 mAh cm^(−2)).In terms of various electrode properties,the presented electrode showed low resistance and excellent electrochemical properties despite the low CNT contents of 0.6 wt%compared to the pristine-applied electrode with 0.85 wt%CNT contents.Moreover,our strategy enables faster drying,which increases the coating speed,thereby offering potential energy savings and supporting carbon neutrality in wet-based electrode manufacturing processes. 展开更多
关键词 cathodes DISPERSIBILITY dispersion solution high-mass-loading lithium-ion batteries
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基于WGAN-GP-Transformer的煤矿瓦斯爆炸风险预警
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作者 冯阳 李国哲 +2 位作者 金柱成 王晓丽 齐占峰 《天津理工大学学报》 2025年第5期155-160,共6页
煤矿瓦斯预警是确保工人健康和安全的重要手段之一。文中提出了利用因果卷积(causal convolutions,Causal Conv)和生成对抗网络(wasserstein generative adversarial network with gradient penalty,WGAN-GP)的WGAN-GPTransformer模型... 煤矿瓦斯预警是确保工人健康和安全的重要手段之一。文中提出了利用因果卷积(causal convolutions,Causal Conv)和生成对抗网络(wasserstein generative adversarial network with gradient penalty,WGAN-GP)的WGAN-GPTransformer模型。首先,通过WGAN-GP技术,平衡瓦斯浓度异常数据量,保证异常数据的充分训练;然后,利用添加因果卷积技术的Transformer模型来进行瓦斯煤矿风险预估。在验证模型有效性的案例研究中,利用了波兰上西里西亚煤矿的瓦斯浓度检测数据。在3~6 min后风险预测的误差评估中,所提出模型在预测准确率上相比传统预测模型提升了10.01%,在收敛时间上相比原Transformer模型降低了3.5倍。这些结果表明,文中提出的模型可以作为管理和降低瓦斯开采风险的有力工具。 展开更多
关键词 深度学习 生成对抗网络 预测准确率 收敛速度
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C-V fractal modeling of the pyrite thermoelectric coefficient and estimation of continuation of ore bodies at depth in the Pujon gold deposit,DPR Korea
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作者 Yon-Ho Kim Chung-Nam O +1 位作者 Kwang-U Choe Kwang-Chol Hwang 《Acta Geochimica》 2025年第6期1377-1394,共18页
This paper describes a method for estimating the continuation of ore bodies at depth based on concentrationvolume(C-V)fractal modeling of the pyrite thermoelectric coefficient in the Pujon gold deposit,Democratic Peo... This paper describes a method for estimating the continuation of ore bodies at depth based on concentrationvolume(C-V)fractal modeling of the pyrite thermoelectric coefficient in the Pujon gold deposit,Democratic People’s Republic of Korea.The method is first established using data in the Kumjomdong area,a well-explored brownfield,and it is then applied to estimate the continuation of ore bodies at depth in the Pyongsandok area,a less-explored greenfield.The methodology consists of four steps:(1)3D modeling of ore bodies using surface geological mapping,mining tunnels in different levels,and a borehole dataset;(2)3D modeling of thermoelectricity coefficients from Au-bearing pyrites based on discrete smooth interpolation and C-V fractal techniques;(3)determination of levels used for calculation of the thermoelectric parameter of pyrite by C-V fractal modeling instead of traditional levels;and(4)determination of the thermoelectric parameter vertical gradient of pyrite reflecting the variation characteristics of pyrite thermoelectricity in the Pujon deposit.The results indicate that(1)pyrites in the Pujon deposit are dominantly P-type,and it is not reasonable to use traditional levels to calculate the thermoelectric parameter of pyrite;(2)thresholds determined by C-V fractal modeling can be used as levels to calculate the thermoelectric parameter of pyrite;(3)the thermoelectric parameter vertical gradient of pyrite ranges from 1 to 2 in the Pujon deposit;and(4)ore body Pyongsan No.9 extends 85 m to 235 m downward from the current borehole location. 展开更多
关键词 Thermoelectricity coefficient of pyrite DSI C-V fractal Pujon gold deposit
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Constitutive modeling to predict flow stress of AerMet 100 ultra-high strength steel in hot working process
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作者 Ri Sung Kim Kyong Ho Sim Hye Yong Ri 《Journal of Iron and Steel Research International》 2025年第9期2834-2846,共13页
The phenomenological and physically based models,using the true stress–true strain curve data obtained under various hot working conditions of 850–1200°C and 0.001–10 s−1,were developed and improved for AerMet... The phenomenological and physically based models,using the true stress–true strain curve data obtained under various hot working conditions of 850–1200°C and 0.001–10 s−1,were developed and improved for AerMet 100 ultra-high strength steel.The predictability of the developed constitutive models was verified and compared.The determination coefficient and average absolute relative error were 0.9988 and 3.72%for the improved version of the modified Zerilli–Armstrong model,0.9985 and 3.96%for the improved version of the modified Johnson–Cook model,0.9947 and 4.59%for the strain-compensated Arrhenius-type model and 0.9913 and 5.43%for the improved Khan–Huang–Liang model,respectively.The results showed that the improved versions of the modified Zerilli–Armstrong model have the best predictability among the studied constitutive models.Comparing the predictability before and after the improvement,the average absolute relative error was increased by 65.14%for the modified Zerilli–Armstrong model and 58.45%for the modified Johnson–Cook model.This indicates that the phenomenological improvement of physically based constitutive models allows us to develop effectively constitutive equations with high prediction accuracy. 展开更多
关键词 AerMet 100 steel High-temperature flow stress Arrhenius-type model Johnson-Cook model Khan-Huang-Liang model Zerilli-Armstrong model
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Solution of multigroup neutron diffusion equation in 3D hexagonal geometry using nodal Green's function method
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作者 Il-Mun Ho Kum-Hyok Ok Chol So 《Nuclear Science and Techniques》 2025年第9期33-42,共10页
In this paper,we propose a numerical calculation model of the multigroup neutron diffusion equation in 3D hexagonal geometry using the nodal Green's function method and verified it.We obtained one-dimensional tran... In this paper,we propose a numerical calculation model of the multigroup neutron diffusion equation in 3D hexagonal geometry using the nodal Green's function method and verified it.We obtained one-dimensional transverse integrated equations using the transverse integration procedure over 3D hexagonal geometry and denoted the solutions as a nodal Green's functions under the Neumann boundary condition.By applying a quadratic polynomial expansion of the transverse-averaged quantities,we derived the net neutron current coupling equation,equation for the expansion coefficients of the transverse-averaged neutron flux,and formulas for the coefficient matrix of these equations.We formulated the closed system of equations in correspondence with the boundary conditions.The proposed model was tested by comparing it with the benchmark for the VVER-440 reactor,and the numerical results were in good agreement with the reference solutions. 展开更多
关键词 NGFM Hexagonal geometry Multigroup neutron diffusion equation
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A Meshfree Approach for Dynamic Analysis of Sandwich Conical and Cylindrical Shells with Varying Thicknesses
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作者 Songhun Kwak Yon Kim +1 位作者 Jongguk Yun Unjong Jo 《Acta Mechanica Solida Sinica》 2025年第4期713-738,共26页
In this paper,a meshfree Jacobi point interpolation(MJPI)approach for the dynamic analysis of sandwich laminated conical and cylindrical shells with varying thickness is presented.The theoretical formulations for sand... In this paper,a meshfree Jacobi point interpolation(MJPI)approach for the dynamic analysis of sandwich laminated conical and cylindrical shells with varying thickness is presented.The theoretical formulations for sandwich laminated shells with varying thickness are established using the modified variational principle within the framework of first-order shear deformation theory(FSDT).The displacement components of the sandwich shell are expanded using the MJPI shape function and Fourier series in the meridional and circumferential directions,respectively.The accuracy and reliability of the proposed MJPI shape function are validated against numerical results from published literature and the commercial simulation tool Abaqus.Finally,the effects of different parameters such as thickness gradient,thickness power index and boundary condition on the free vibration and dynamic response of the sandwich laminated shell are investigated. 展开更多
关键词 Meshfree Jacobi point interpolation Dynamic analysis Varying thickness Sandwich laminated shell
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Overcoming transparency limitations in 3D-printed yttria ceramics
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作者 Sinuo Zhang Chang Woo Gal +5 位作者 Imam Akbar Sutejo Shakeel Abbas Yeong-Jin Choi Ha-Neul Kim Young-Jo Park Hui-suk Yun 《Journal of Materials Science & Technology》 2025年第22期59-71,共13页
Microstructure and surface roughness are two critical factors governing the transparency of transparent ceramics.The manufacturing mechanism of additive manufacturing(AM)layer by layer is destined that the layer thick... Microstructure and surface roughness are two critical factors governing the transparency of transparent ceramics.The manufacturing mechanism of additive manufacturing(AM)layer by layer is destined that the layer thickness has an important influence on the microstructure and surface quality of the printed workpiece.Simultaneously,the occurrence of the stair-stepping phenomenon unavoidably results in a significant surface roughness.Therefore,in this study,yttria(Y_(2)O_(3))transparent ceramics with different printing layer thicknesses were fabricated by AM to investigate the effect of layer thickness on its optical and mechanical properties.The findings indicate that an increase in the layer thickness correlates with a heightened density in the printed green bodies,subsequently leading to enhanced transmittance in the final sintered body.When the layer thickness approximates or falls below the size of large particle agglomerations found in ceramic powders,numerous pores,and voids emerge within the green bodies.Significantly,at a layer thickness of 45µm,the in-line transmittance of Y_(2)O_(3)can reach up to 97.73%of the theoretical limit.In addition,the surface roughness of the Y_(2)O_(3)ceramics decreased as the layer thickness increased.To facilitate the further transition from translucent to transparent 3D Y_(2)O_(3)structures,a vibration-assisted chemical-mechanical polishing technique was developed by replacing water with a colloidal SiO_(2) suspension.This technique resulted in a significant reduction in the surface roughness of the Y_(2)O_(3)ceramics by 95.42%and eliminated the stair-stepping phenomenon caused by AM,thus increasing 66.12%of the in-line transmittance.These enhancements expand their potential applications in laser amplification,optical communications,and other areas requiring high-transparency materials.The method developed in this study can be used for the AM-based fabrication of transparent 3D polycrystalline ceramics. 展开更多
关键词 Additive manufacturing YTTRIA Layer thickness Surface roughness Optical properties
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Pills as Aids?Substance Use,School Satisfaction,Sleep Quality,Body Image,and MentalWell-Being Among Korean Adolescents
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作者 Wufan Jia Seung Hee Yoo Hye Eun Lee 《International Journal of Mental Health Promotion》 2025年第12期1897-1906,共10页
Background:With growing concerns about the abuse of prescription and over-the-counter(OTC)medications,such as medications for attention-deficit/hyperactivity disorder(ADHD),diet pills,and sleep aids,among adolescents ... Background:With growing concerns about the abuse of prescription and over-the-counter(OTC)medications,such as medications for attention-deficit/hyperactivity disorder(ADHD),diet pills,and sleep aids,among adolescents in South Korea,this study aimed to investigated how these substances affect key aspects of adolescent well-being,specifically school satisfaction,body image,and sleep quality,and their association with mental health outcomes.Methods:A two-wave longitudinal survey was conducted with Korean female high school students(Wave 1:n=494;Wave 2:n=189).Linear regression analyses were used to evaluate the effects of ADHD medications,diet pills,and sleep aids on changes in school satisfaction,body image,and sleep quality,respectively.We also examined the relationship between these outcomes and mental health indicators,including depression,anxiety,stress,and somatic symptoms.Results:In line with the Self-Medication Hypothesis,which suggests that substances may fail to alleviate stress or improve well-being,the use of ADHD medications was associated with a decrease in school satisfaction,diet pill use was not significantly associated with changes in body image,and sleep aid use was not significantly associated with changes in sleep quality.Poor school satisfaction,body image,and sleep quality were associated with negative mental health outcomes.Conclusion:These findings suggest that ADHD medications,diet pills,and sleep aids may not effectively improve school satisfaction,body image,or sleep quality,and could potentially exacerbate mental health challenges. 展开更多
关键词 Adolescents substance use mental health SELF-MEDICATION coping strategies
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Restructuring the cell network of non-equiatomic CoCrFeNiMoC medium-entropy alloy fabricated by laser powder bed fusion
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作者 Hyeonseok Kwon Eun Seong Kim +7 位作者 Yoon-Uk Heo Jungho Choe Rae Eon Kim Soung Yeoul Ahn Sang-Ho Oh Jeong Min Park Byeong-Joo Lee Hyoung Seop Kim 《Journal of Materials Science & Technology》 2025年第11期143-152,共10页
Metal additive manufacturing(MAM)enables near-net shape production of components with minimized waste and excellent mechanical performance based on multi-scale microstructural heterogeneity.Espe-cially,the dislocation... Metal additive manufacturing(MAM)enables near-net shape production of components with minimized waste and excellent mechanical performance based on multi-scale microstructural heterogeneity.Espe-cially,the dislocation cell network that often bears elemental segregation or precipitation of a secondary phase contributes to enhancing the strength of additively manufactured materials.The cell boundaries can also act as active nucleation sites for the formation of precipitates under post-MAM heat treatment,as the chemical heterogeneity and profuse dislocations generate a driving force for precipitation.In this work,we subjected a Co_(18)Cr_(15)Fe_(50)Ni_(10)Mo_(6.5)C_(0.5)(at%)medium-entropy alloy fabricated by laser powder bed fusion(LPBF)to post-LPBF annealing at 900℃for 10 min.Microstructural investigation revealed that the cell boundaries of the as-built sample,which were decorated by Mo segregation,are replaced byμphase andM_(6)C typecarbide precipitatesduringannealingwhile thegrainstructureand sizeremain unaffected,indicating that the post-LPBF annealing delivered the proper amount of heat input to alter only the cell structure.The yield strength slightly decreased with annealing due to a reduction in the strengthening effect by the cell boundaries despite an increased precipitation strengthening effect.How-ever,the post-LPBF annealing improved the strain hardenability and the ultimate tensile strength was enhanced from∼1.02 to∼1.15 GPa owing to reinforced back stress hardening by the increased disloca-tion pile-up at the precipitates.Our results suggest that the cell structure with chemical heterogeneity can be successfully controlled by careful post-MAM heat treatment to tailor the mechanical performance,while also providing insight into alloy design for additive manufacturing. 展开更多
关键词 Laser powder bed fusion Medium-entropy alloy Cell structure Strain hardening Precipitation Back stress hardening
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Real-world-evidence,prospective-observational study to evaluate safety and effectiveness of rabeprazole dual-delayed-release capsules in patients with gastroesophageal reflux disease
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作者 Parimal Lawate Virender Chauhan +7 位作者 Lingampalli Rajendra Prasad Abhimanrao Pawar Atul G Puranik Alok Bansal Abhiram Koganti Ashok Jaiswal Pranali Puradkar Kunal Jhaveri 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 2025年第1期37-45,共9页
BACKGROUND Abnormal gastric acid reflux into the esophagus causes symptoms of gastroeso-phageal reflux disease(GERD)such as heartburn and regurgitation and also leads to mucosal damage.This damage can further lead to ... BACKGROUND Abnormal gastric acid reflux into the esophagus causes symptoms of gastroeso-phageal reflux disease(GERD)such as heartburn and regurgitation and also leads to mucosal damage.This damage can further lead to complications such as Bar-rett’s esophagus and esophagitis.Conventional proton pump inhibitors(PPIs)often fail to reduce nocturnal acid production,leaving patients with unresolved symptoms that worsen at night and decreased satisfaction.Happi ER,a novel dual delayed-release(DDR)formulation of rabeprazole,aims to address these limitations by providing both immediate and prolonged acid suppression.AIM To evaluate the safety and effectiveness of rabeprazole DDR 20 mg capsule in patients with GERD.METHODS This study involved a multicenter,real-world,prospective,observational design over an eight-week period.A total of 1022 GERD patients were treated with rabeprazole DDR 20 mg capsules(Happi ER),as prescribed by their physicians.We included adult patients with confirmed GERD and persistent heartburn symptoms despite prior PPI use.Outcome measures included heartburn severity,frequency of night-time awakenings,use of rescue medications,and overall patient satisfaction.RESULTS Rabeprazole DDR 20 mg capsules(Happi ER)were shown to be highly effective in treating GERD symptoms.At the end of the study,the mean heartburn score improved significantly from 2.46±0.67 at baseline to 0.16±0.39(P<0.0001).The median number of night-time awakenings decreased to 0(P<0.0001).More than 93%of patients rated the therapy as“excellent”or“very good”,reflecting high satisfaction.No significant adverse effects were reported,and the safety profile was comparable to that of traditional PPIs.CONCLUSION By providing both rapid and sustained acid suppression,Happi ER effectively treats GERD,particularly with respect to night-time symptoms.Its safety and efficacy profile make it a viable option for individuals with mild-to-moderate GERD,significantly improving the quality of life and symptom management. 展开更多
关键词 Gastroesophageal reflux disease HEARTBURN Acid reflux RABEPRAZOLE Dual delayed-release
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不同剂量右美托咪定复合罗哌卡因胸椎旁神经阻滞在非插管胸腔镜手术中的比较 被引量:32
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作者 王雁 邵建林 杨伟 《临床麻醉学杂志》 CAS CSCD 北大核心 2019年第4期323-326,共4页
目的比较不同剂量右美托咪定复合罗哌卡因胸椎旁神经阻滞在非插管胸腔镜手术中的效果。方法择期行胸腔镜肺大泡切除术的患者114例,男90例,女24例,年龄25~60岁,BMI<25 kg/m^2,ASAⅠ或Ⅱ级,随机分为四组。麻醉诱导前行胸椎旁神经阻滞,... 目的比较不同剂量右美托咪定复合罗哌卡因胸椎旁神经阻滞在非插管胸腔镜手术中的效果。方法择期行胸腔镜肺大泡切除术的患者114例,男90例,女24例,年龄25~60岁,BMI<25 kg/m^2,ASAⅠ或Ⅱ级,随机分为四组。麻醉诱导前行胸椎旁神经阻滞,C组注入0.375%罗哌卡因20 ml, D1、D2、D3组分别注入右美托咪定0.5、1.0、2.0μg/kg复合0.375%罗哌卡因20 ml。记录感觉阻滞起效时间和持续时间;入室时(T_0)、注药后30 min(T_1)、手术开始时(T_2)、手术开始后30 min(T_3)的RR、PaO_2和PaCO_2;术毕全麻药的用量;术中低血压、心动过缓和使用麻黄碱与阿托品的情况。结果与C、D1组比较,D2、D3组感觉阻滞起效时间明显缩短(P<0.05),持续时间明显延长(P<0.05),T_2、T_3时PaCO_2明显降低(P<0.05),RR、PaO_2明显升高(P<0.05),术毕丙泊酚和瑞芬太尼的用量明显减少(P<0.05);D3组心动过缓和低血压的发生率明显高于其他三组(P<0.05)。结论右美托咪定1.0μg/kg复合罗哌卡因行胸椎旁神经阻滞可缩短感觉阻滞起效时间,延长持续时间,减少全麻药用量,无明显血流动力学不良反应发生。 展开更多
关键词 胸椎旁神经阻滞 罗哌卡因 右美托咪定
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纯铜高压扭转压缩阶段塑性变形的实验及有限元分析(英文) 被引量:4
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作者 王文珂 宋月鹏 +5 位作者 高东升 JungHwan Lee EunYoo Yoon DongJun Lee ChongSoo Lee HyoungSeop Kim 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2013年第S2期301-304,共4页
利用实验及有限元分析等手段,对纯铜高压扭转压缩阶段的塑性变形行为、硬度及显微组织分布进行了研究,结果表明,试样经压缩后,其硬度分布极为不均匀,边缘硬度高,轴心部位硬度低,而中间部位硬度变化较为平缓。模拟结果显示,试样在压缩过... 利用实验及有限元分析等手段,对纯铜高压扭转压缩阶段的塑性变形行为、硬度及显微组织分布进行了研究,结果表明,试样经压缩后,其硬度分布极为不均匀,边缘硬度高,轴心部位硬度低,而中间部位硬度变化较为平缓。模拟结果显示,试样在压缩过程中的应力应变呈不均匀变化,由此引起试样各部位显微组织及晶粒变形不均匀。进一步研究表明,试样与模具间的摩擦对于压缩阶段试样变形具有重要影响。 展开更多
关键词 塑性变形(SPD) 高压扭转(HPT) 压缩阶段 塑性变形 不均匀分布
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基于小波变换相位差的压缩机内部模态失速先兆分析(英文) 被引量:5
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作者 薛翔 王彤 安正浩 《风机技术》 2017年第3期20-28,共9页
由于模态波经常作为一种失速先兆出现在压缩机发生失速前,因而对它的识别与分析都非常重要。近年来,小波变换被越来越多的研究者用来分析失速先兆,然而很少有人关注小波变换原始的表达式。基于对前人模态失速理论的深刻理解和小波变换... 由于模态波经常作为一种失速先兆出现在压缩机发生失速前,因而对它的识别与分析都非常重要。近年来,小波变换被越来越多的研究者用来分析失速先兆,然而很少有人关注小波变换原始的表达式。基于对前人模态失速理论的深刻理解和小波变换的进一步推导,本文提出了一种用来分析模态波特征的新方法。这种方法需要使用叶轮进口或出口附近周向的动态压力数据。而当小波变换的两个特定条件满足时,模态波的模态数和传播速度等可以通过小波变换的相位差得到。该方法的可行性使用已公布的一台轴流压缩机实验数据进行了验证,也同时在一台离心压缩机上进行相关实验。通过该方法,可以判断出动态信号中明显的波动成分属不属于模态失速,同时得到模态波的特征参数。因而,这种新方法可以作为压缩机内部模态失速分析的一种前处理手段。 展开更多
关键词 失速先兆 模态失速 压缩机 小波变换
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WebDewey和电子版LCSH组配技术探微 被引量:2
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作者 王忠红 《图书馆杂志》 CSSCI 北大核心 2007年第12期22-25,共4页
本文简要介绍了电子版杜威十进分类法和美国国会主题词表的特点,并从使用角度通过具体例子详尽分析了两者采用的组配技术。
关键词 视窗杜威 美国国会主题词表 组配
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云桂线富宁隧道围岩分级变更分析 被引量:7
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作者 刘伟 吴朝钢 +1 位作者 张瑞 周飞棚 《隧道建设(中英文)》 北大核心 2018年第6期895-900,共6页
为提高隧道勘察围岩分级的准确性,减小施工阶段围岩变更率,对云桂线富宁隧道围岩分级变更进行分析,主要结论与建议如下:1)造成该隧道围岩分级变更的主要原因是物探解译不准、岩溶发育、岩体层间挤压破碎和地下水发育,其中物探解译不准... 为提高隧道勘察围岩分级的准确性,减小施工阶段围岩变更率,对云桂线富宁隧道围岩分级变更进行分析,主要结论与建议如下:1)造成该隧道围岩分级变更的主要原因是物探解译不准、岩溶发育、岩体层间挤压破碎和地下水发育,其中物探解译不准的原因有异常段飘移、断层破碎带解译过宽及解译错误等;2)岩溶发育造成的变更量也较大,应重视可溶岩段围岩分级的确定,避免出现长段高围岩分级;3)因岩体层间挤压破碎及地下水发育造成的围岩变更率一般较小,需在施工阶段结合超前地质预报进行变更;4)地质条件复杂的长大深埋隧道采用可控源音频大地电磁法是适宜的,但应解决物探解译过程中存在的问题,布置钻孔对物探异常区进行验证,提高解译精度;5)目前采用的综合勘察手段仍是确定铁路隧道围岩分级的主要方法,施工中应重视超前地质预报及施工地质工作。 展开更多
关键词 富宁隧道 围岩分级 物探 围岩分级变更 超前地质预报
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二氧化钛纳米管在骨科的研究进展 被引量:1
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作者 董俊杰 黄云超 +2 位作者 向柄全 杨延龙 刘建雄 《生物骨科材料与临床研究》 CAS 2018年第2期61-65,共5页
查阅国内外有关二氧化钛纳米管(TiO_2纳米管)在骨科领域(实验研究)的文献,并进行归纳分析,总结TiO_2纳米管在骨科领域的研究现状及进展。TiO_2纳米管是一种新型纳米材料,阳极氧化法、模板合成法和水热合成法是目前常用的3种制备方法,Ti... 查阅国内外有关二氧化钛纳米管(TiO_2纳米管)在骨科领域(实验研究)的文献,并进行归纳分析,总结TiO_2纳米管在骨科领域的研究现状及进展。TiO_2纳米管是一种新型纳米材料,阳极氧化法、模板合成法和水热合成法是目前常用的3种制备方法,TiO_2纳米管在骨科的研究集中在组织相容性(促骨融合与骨生长)和表面修饰(载物载药)方面。TiO_2纳米管有良好的抗菌性与组织相容性,可载药载物,在抗菌、抗肿瘤、促骨生长方面具有良好的发展前景和研究价值。 展开更多
关键词 二氧化钛纳米管 骨科 研究进展
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傩仪的逻辑:社会规则与村落日常秩序建构——基于白族傩仪“耳子歌”的研究 被引量:1
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作者 李容芳 《原生态民族文化学刊》 CSSCI 2018年第2期108-115,共8页
城市化背景下,村落终结成为普遍诊断。当村落传统文化遭遇价值多元化,村落共同体内部结构引发传统文化的式微,社会规则遵从下的村落内部整合与维系力成为焦点。通过对白族村落"耳子歌"傩仪的田野调查,展现村落集体表象展演的... 城市化背景下,村落终结成为普遍诊断。当村落传统文化遭遇价值多元化,村落共同体内部结构引发传统文化的式微,社会规则遵从下的村落内部整合与维系力成为焦点。通过对白族村落"耳子歌"傩仪的田野调查,展现村落集体表象展演的行动逻辑,揭示傩仪对村落共同体日常秩序建构的作用。通过傩仪变迁语境的分析,可对变迁语境下傩仪的社会价值与行动逻辑如何与社会规则互动进行解读,并进一步论证村落日常秩序建构何以可能。 展开更多
关键词 傩仪 社会规则 耳子歌 村落日常秩序 白族
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境脉因素对TPACK在教学实践中的应用影响研究 被引量:2
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作者 林芳竹 张哲 +1 位作者 金哲 张海 《数字教育》 2015年第2期6-11,共6页
在以学校为基础的环境中,教师需要考虑诸如技术的有效性、学校政策等境脉因素,因为它们适用TPACK来解决教学问题。然而,定性的TPACK研究倾向于例证TPACK的七种结构,其境脉的影响尚未详细地阐明过。新加坡研究者运用一个框架将TPACK和四... 在以学校为基础的环境中,教师需要考虑诸如技术的有效性、学校政策等境脉因素,因为它们适用TPACK来解决教学问题。然而,定性的TPACK研究倾向于例证TPACK的七种结构,其境脉的影响尚未详细地阐明过。新加坡研究者运用一个框架将TPACK和四种影响教师ICT课程设计的境脉因素(物理/技术,文化/制度,人际以及内省)之间的相互作用可视化表示出来。研究者通过转录教师音频的讨论内容分析以及编码频率的卡方分析来自新加坡一所小学的24名教师关于课程设计的讨论结果。同时,新加坡研究团队由一名经验丰富的教育技术专家协助,也证明了TPACK的高出现率。另外,教师还需要开发促进和讨论教学设计的能力,使其对于境脉的关注可以转化为支持教学改进的机遇。 展开更多
关键词 TPACK ICT 境脉因素
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磁控溅射方法制备(CoCr/Pt)20纳米多层膜及表征
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作者 黄阀 李宝河 +2 位作者 杨涛 翟中海 朱逢吾 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第z1期65-69,共5页
采用磁控溅射方法制备了性能优良的以Pt为缓冲层的(CoCr/Pt)20纳米多层膜,研究了溅射气压对(CoCr/Pt)20纳米多层膜的微结构和磁性的影响.结果表明,Ar溅射气压对(CoCr/Pt)20纳米多层膜的微结构、垂直磁各向异性和矫顽力有很大的影响.所... 采用磁控溅射方法制备了性能优良的以Pt为缓冲层的(CoCr/Pt)20纳米多层膜,研究了溅射气压对(CoCr/Pt)20纳米多层膜的微结构和磁性的影响.结果表明,Ar溅射气压对(CoCr/Pt)20纳米多层膜的微结构、垂直磁各向异性和矫顽力有很大的影响.所有样品的有效各向异性常数Ke.>0,具有垂直磁各向异性.X射线衍射结果显示,小角衍射峰很锐,样品有良好的周期性层状结构.随着Ar溅射气压增加,样品垂直膜面的矫顽力增加,但样品有效磁各向异性常数减小.原子力显微镜照片显示,随着Ar溅射气压增加,其表面平均晶粒尺寸和粗糙度均增加,这是导致多层膜的垂直矫顽力增加和有效磁各向异性常数减小的因素. 展开更多
关键词 溅射气压 纳米多层膜 垂直磁各向异性 有效磁各向异性常数
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卧式CSTR生物制氢反应器设计与流场数值模拟 被引量:3
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作者 李峰哲 丁杰 +2 位作者 郭婉茜 金正首 任南琪 《太阳能学报》 EI CAS CSCD 北大核心 2021年第10期305-310,共6页
为在一定程度上弥补连续流搅拌槽式反应器(CSTR)生物制氢反应器的缺陷,及指导生物制氢反应器的放大设计,该文研究设计卧式CSTR制氢反应器。采用多重参考系法(MRF)和标准k-ε湍流模型模拟在50 r/min的较低转速下具有相同桨径、不同叶宽... 为在一定程度上弥补连续流搅拌槽式反应器(CSTR)生物制氢反应器的缺陷,及指导生物制氢反应器的放大设计,该文研究设计卧式CSTR制氢反应器。采用多重参考系法(MRF)和标准k-ε湍流模型模拟在50 r/min的较低转速下具有相同桨径、不同叶宽结构的5种搅拌桨(搅拌桨的叶宽W分别为30、40、50、60、70 mm)的搅拌特性。结果表明叶宽为60 mm的搅拌桨能产生合理的径向、轴向速度分布使活性污泥与底物充分接触,适合生物制氢反应器的工艺需要。通过计算得到不同叶宽结构下的搅拌功率与扭矩,对进一步研究生物制氢反应器的工业化应用和运行控制提供参考价值。 展开更多
关键词 生物制氢 卧式连续流搅拌槽式反应器 计算流体力学 流场数值模拟 生物制氢反应器
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