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自由锻造车间的自动化和节能实施

大型铸锻件 1982年第A2期 78-83页

作者： R.Kato s.nagata T.Tsuruki M.Amamoto 齐大方

日本住友金属工业有限公司大阪制钢所的自由锻造车间,有两台3000tf水压机,一台立式,一台卧式。但这需要很多人力,能源消耗量也很大,因为两台压力机和许多炉子是分别设置的。针对这种情况,对于立式自由锻压力机和操作机,以及对于炉子的操... 详细信息

日本住友金属工业有限公司大阪制钢所的自由锻造车间,有两台3000tf水压机,一台立式,一台卧式。但这需要很多人力,能源消耗量也很大,因为两台压力机和许多炉子是分别设置的。针对这种情况,对于立式自由锻压力机和操作机,以及对于炉子的操作,引用了计算机控制系统。其结果,人力减少30％,节能40％。对于自由锻压力机及其操作机,引用了半自动固定型和完全程序操作的成套电子计算机控制系统;对于炉子,采用集中控制系统,十五台分批式加热炉和退火炉都改为直接数字控制。

关键词：锻造车间自由锻节能计算机控制系统自动化集中控制系统直接数字控制能源消耗量

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三栅调制B-A规

真空 1979年第4期 47-50页

作者： T.Kanaji s.Nakamura T.Urano s.nagata 李昌全日本神户大学工程系

研究了一种三栅调制Ｂ－Ａ规，这种规有两个附加的同心栅极，位于普通ＢＡ规的电子收集栅（Ｇ１）的内侧。内栅（Ｇ３）维持在恒定的电位，以保持恒定的光电流。通过改变Ｇ２的电位来调制离子流，但是灯丝，Ｇ１和Ｇ２之间的电位关系不... 详细信息

研究了一种三栅调制Ｂ－Ａ规，这种规有两个附加的同心栅极，位于普通ＢＡ规的电子收集栅（Ｇ１）的内侧。内栅（Ｇ３）维持在恒定的电位，以保持恒定的光电流。通过改变Ｇ２的电位来调制离子流，但是灯丝，Ｇ１和Ｇ２之间的电位关系不改变，以保持热电子流不被扰乱。在“调制”状态下的Ｓ值（即灵敏度－译者注）是３托－１（即２ ×１０－２帕－１）。没有检测到由于调制引起的电子激励气体解吸。避免从Ｇ２发射的光电子的影响是重要的。

关键词：收集极光电子差值 B-A 光电流离子流

Epidemiological impact of revoking mask-wearing recommendation on COVID-19 transmission in Tokyo,Japan

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Infectious Disease Modelling 2024年第4期9卷 1289-1300页

作者： Mayu nagata Yuta Okada Hiroshi Nishiura Kyoto University school of Public Health Yoshida-KonoeSakyoKyoto606-8601Japan

Despite the global implementation of COVID-19 mitigation measures,the disease continues to maintain *** mask wearing became one of the key measures for preventing the transmission of COVID-19 early in the pandemic period,many countries have relaxed the mandatory or recommended wearing of *** objective of the present study was to estimate the epidemiological impact of removing the mask-wearing recommendation in *** developed a model to assess the consequences of declining mask-wearing coverage after the government revoked its recommendation in February *** declining mask-wearing coverage was estimated using serial cross-sectional data,and a mathematical model was devised to determine the age-specific incidence of COVID-19 using the observed case count in Tokyo from week of October 3,2022 to October 30,*** explored model-based counterfactual scenarios to measure hypothetical situations in which the mask-wearing coverage decreases or increases relative to the observed *** results show that mask-wearing coverage declined from 97%to 69%by the week of October 30,2023,and that if the mask-wearing recommendation had continued,427 lives could have been saved in *** the mask-wearing coverage had declined to 25%of the observed level,the model suggests there might have been 1587 additional ***,revoking the mask-wearing recommendation had a substantial epidemiological *** future pandemics,our proposed approach could provide a realtime quantification of the effects of relaxing countermeasures.

关键词： COVID-19 Mask wearing recommendation Health policy Counterfactual Mathematical model

胰腺导管腺癌动脉侵犯的确诊：CT的最佳诊断标准是什么？

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国际医学放射学杂志 2023年第4期 491-491页

作者： Y.Noda N.Mizuno N.Kawai T.Ando M.Kawaguchi s.nagata 肖诗蕾

摘要目的研究确定胰腺导管腺癌（PDAC）动脉侵犯的诊断效能和观察者间变异性，并确定最佳CT成像标准。方法回顾性收集128例术前接受CT增强扫描的PDAC病人（男

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Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

First evidence for chiral wobbling of triaxial nuclei

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Nuclear science and Techniques 2024年第7期35卷 4-7页

作者： s.Frauendorf Department of Physics and Astronomy University of Notre DameNotre DameIN 46556USA

Chirality(Greek“handiness”)is a property of many com-plex *** molecules exist in two forms,one being the mirror image of the *** for our hands,it is impossible to make the images identical by a suitable *** two forms are called left-handed and *** have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a *** properties that are insensitive to the geometry are also the *** different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same ***,the geometrical differences between the two species may have other *** two species of the carvon molecule shown in Fig.1 taste quite differently.

关键词： turns Chiral mirror

Tribological behavior of lubricant-impregnated porous polyimide

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Friction 2024年第4期12卷 711-725页

作者： Jinbang LI Ningning ZHOU Janet s.s.WONG school of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(PPI)with different densities were ***(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire *** operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing PPI *** moduli,E*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that E*rises with *** high density PPIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil *** of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI *** low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

Enhancing fatigue performance of AZ31 magnesium alloy components fabricated by cold metal transfer-based wire arc directed energy deposition through LPB

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Journal of Magnesium and Alloys 2024年第4期12卷 1638-1662页

作者： shambhu Kumar Manjhi srikanth Bontha A.s.s.Balan Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkalSrinivasanagarMangaloreKarnataka 575025India

Cold Metal Transfer-Based Wire Arc Directed Energy Deposition(CMT-WA-DED)presents a promising avenue for the rapid fabrication of components crucial to automotive,shipbuilding,and aerospace ***,the susceptibility to fatigue of CMT-WA-DED-produced AZ31 Mg alloy components has impeded their widespread adoption for critical load-bearing *** this study,a comprehensive investigation into the fatigue behaviour of WA-DED-fabricated AZ31 Mg alloy has been carried out and compared to commercially available wrought AZ31 *** findings indicate that the as-deposited parts exhibit a lower fatigue life than wrought Mg alloy,primarily due to poor surface finish,tensile residual stress,porosity,and coarse grain microstructure inherent in the WA-DED *** Plasticity Burnishing(LPB)treatment is applied to mitigate these issues,which induce significant plastic deformation on the *** treatment resulted in a remarkable improvement of fatigue life by 42%,accompanied by a reduction in surface roughness,grain refinement and enhancement of compressive residual stress ***,during cyclic deformation,WA-DED specimens exhibited higher plasticity and dislocation density compared to both wrought and WA-DED+LPB specimens.A higher fraction of Low Angle Grain Boundaries(LAGBs)in WA-DED specimens contributed to multiple crack initiation sites and convoluted crack paths,ultimately leading to premature *** contrast,wrought and WA-DED+LPB specimens displayed a higher percentage of High Angle Grain Boundaries(HAGBs),which hindered dislocation movement and resulted in fewer crack initiation sites and less complex crack paths,thereby extending fatigue *** findings underscore the effectiveness of LPB as a post-processing technique to enhance the fatigue performance of WA-DED-fabricated AZ31 Mg alloy *** study highlights the importance of LPB surface treatment on AZ31 Mg components produced by CMT-WA-DED to remove surface d

关键词： Wire arc additive manufacturing AZ31 Mg alloy Low plasticity burnishing Low cycle fatigue test strain amplitude

Ren-integrable and ren-symmetric integrable systems

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Communications in Theoretical Physics 2024年第3期76卷 62-69页

作者： s Y Lou school of Physical science and Technology Ningbo UniversityNingbo315211China

A new type of symmetry,ren-symmetry,describing anyon physics and corresponding topological physics,is ***-symmetry is a generalization of super-symmetry which is widely applied in super-symmetric physics such as super-symmetric quantum mechanics,super-symmetric gravity,super-symmetric string theory,super-symmetric integrable systems and so *** and Grassmann numbers are,in some sense,dual conceptions,and it turns out that these conceptions coincide for the ren situation,that is,a similar conception of ren-number(R-number)is devised for *** particular,some basic results of the R-number and ren-symmetry are exposed which allow one to derive,in principle,some new types of integrable systems including ren-integrable models and ren-symmetric integrable *** examples of ren-integrable KdV-type systems and ren-symmetric KdV equations are explicitly given.

关键词： symmetries integrable systems anyon physics extended supersymmetry ren-symmetry