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Is There an Absolute scale for speed?

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Journal of Modern Physics 2022年第8期13卷 1184-1196页

作者： Ricardo b. Ferreira Joã o b. Ferreira Instituto superior de Agronomia University of Lisbon Lisbon Portugal Instituto Português de Oncologia de Lisboa Francisco Gentil Lisbon Portugal

Except for the speed of photons in vacuum, all speeds are relative. Could we develop an absolute scale for speed in which relative values for speed may be arbitrarily positioned and compared in absolute terms? The currently accepted definition for the meter as the distance covered by photons in vacuum during 1/299,792,458 s, and the view that the greater a material particle is accelerated towards c, the greater time dilation and length contraction will be, suggest that anything disturbing one of the four spacetime dimensions may affect the other three as well. One hypothetical experiment, one real experiment performed in the 1970s, and one experiment from a different field of science are discussed to propose that both time and velocity are only partially relative. In the first experiment, person A is standing still on the Earth’s surface, and person b is onboard a train passing by person A at the constant speed of 60 km/h (as measured by person b on the train’s speedometer). Persons A and b define two distinct inertial frames of reference, which correspond to two different spacetime conditions and which are therefore characterized by comparatively different lengths of the meter and durations of the second, as predicted by the Lorentz factor. Therefore, if person b onboard the train measures the train’s speed relative to person A as 60 km/h, a simple calculation will show that person A will perceive the train passing by at 59.99999999999981455834 km/h. If we consider the speed of photons in vacuum (c = 299,792,458 m/s) as a universal reference, and if we consider that the greater a material particle is accelerated towards c, the greater time dilation and length contraction will be, then person C, occupying an independent, distinct inertial frame of reference, will be unable to determine persons A and b’s absolute speeds, but may infer which one is moving at a speed closer to c by comparing, with his own meter and second, the durations of the second and the lengths of

关键词： spacetime Relativity speed of Light space Time

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工业型多重力分选机的扩大试验

有色矿冶 1992年第5期8卷 19-24页

作者： b.s.K.CHAN R.H.MOZLEY G.J.C.CHILDs 罗中平

本文介绍了用工业型多重力分选机(mGs)处理锡、铬铁矿、天青石和磁铁矿粉的扩大试验结果。结果表明,MGs能够获得优于传统设备的分选效果。

关键词：多重力选矿机重力选矿

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砷化镓注入式激光雷达

红外与激光工程 1973年第4期 47-60页

作者： b.s.Goldstein G.F.Dalrymple

评价了在微弱的和强的背景辐射条件下砷化镓激光雷达对连续目标和角反射器的测距能力。对空间环境作了计算。制作了一部实验砷化镓激光雷达。展示了在大气中用这部雷达对几个漫反射目标和一个角反射器所获得的工作结果。

关键词：激光雷达光雷达角反射器伪装器材光电子散粒噪声散弹噪声暗电流背景辐射视场注入式光电倍增管球面度砷化镓砷化物

six end-stage renal disease patients benefited from first non-simultaneous single center 6-way kidney exchange transplantation in India

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World Journal of Nephrology 2016年第6期5卷 531-537页

作者： Vivek b Kute Himanshu V Patel Umesh T Varyani Pankaj R shah Pranjal R Modi Veena R shah sayyed J Rizvi bipin C Pal Priya s shah Pavan s Wakhare Vijay A Ghodela saiprasad G shinde Varsha b Trivedi Minaxi H Patel Hargovind L Trivedi Department of Nephrology and Clinical Transplantation Institute of Kidney Diseases and Research Center Dr HL Trivedi Institute of Trans-plantation Sciences Department of Urology and Transplantation Dr HL Trivedi Institute of Trans-plantation Sciences Department of Anesthesia Dr HL Trivedi Institute of Transplantation Sciences Department of Pathology and laboratory medicine Dr HL Trivedi Institute of Transplantation Sciences

AIM To avoid desensitization protocols and AbO incompatible kidney transplantation(KT) due to high costs and increased risk of infections from intense *** We present institutional ethical review board- approved study of single center 6-way kidney exchange transplantation. The participants comprised AbO incompatibility(n = 1); positive cross-match and/or presence of donor specific antibody(n = 5). The average time required from registration in kidney paired donation(KPD) registry to find suitable donors was 45 d and time required to perform transplants after legal permission was 2 mo. REsULTs Graft and patient survival were 100%, and 100%, respectively. One patient had biopsy-proven acute borderline T cell rejection(banff update 2013, type 3). Mean serum creatinine was 0.8 mg/dL at 9 mo followup. The waiting time in KPD was short as compared to deceased donor KT. CONCLUsION We report first non-simultaneous, single center, 6-way kidney exchange transplantation from India. Our experience will encourage other centers in India to undertake this practice.

关键词： Kidney transplantation/methods Kidney paired donation Living donors/supply and distribution Donor selection/methods

soft monolithic infrared neural interface for simultaneous neurostimulation and electrophysiology

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Light(science & Applications) 2023年第6期12卷 1103-1116页

作者： Marcello Meneghetti Jaspreet Kaur Kunyang sui Jakob F.sørensen Rune W.berg Christos Markos DTU Electro Department of Electrical and Photonics EngineeringTechnical University of DenmarkDK-2800 KgsLyngbyDenmark Department of Neuroscience University of CopenhagenBlegdamsvej 3BDK-2200 Kbh NCopenhagenDenmark NORbLIs Aps Virumgade 35DDK-2830 VirumDenmark

Controlling neuronal activity using implantable neural interfaces constitutes an important tool to understand and develop novel strategies against brain *** neurostimulation is a promising alternative to optogenetics for controlling the neuronal circuitry with high spatial ***,bi-directional interfaces capable of simultaneously delivering infrared light and recording electrical signals from the brain with minimal inflammation have not yet been ***,we have developed a soft fibre-based device using high-performance polymers which are>100-fold softer than conventional silica glass used in standard optical *** developed implant is capable of stimulating the brain activity in localized cortical domains by delivering laser pulses in the 2μm spectral region while recording electrophysiological *** and local field potentials were recorded in vivo from the motor cortex and hippocampus in acute and chronic settings,*** analysis of the brain tissue indicated insignificant inflammatory response to the infrared pulses while the signal-to-noise ratio of recordings still remained *** neural interface constitutes a step forward in expanding infrared neurostimulation as a versatile approach for fundamental research and clinically translatable therapies.

关键词： neural stimulation recording

Dynamic microstructure evolution and mechanical properties of dilute Mg-Al-Ca-Mn alloy during hot rolling

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Journal of Materials science & Technology 2022年第34期129卷 1-14页

作者： shiwei Xu Congcong Zhu Zhanhong Lin Chen Jin s.Kamado K.Oh-ishi Yun Qin College of Materials science and Engineering Hunan UniversityChangsha 410082China state Key Laboratory of Advanced Design and Manufacturing for Vehicle body Hunan UniversityChangsha 410082China Qinghai salt Lake Teli Magnesium Co.Ltd. Xining 810000China Department of Mechanical Engineering Nagaoka University of TechnologyNagaoka 940-2188Japan Toyota Central R&D Labs. Inc.41-1 YokomichiNagakuteAichi 480-1192Japan Research Institute(R&D Centre) Baowu Steel Group CorporationShanghai 201900China

The dynamic microstructure and texture of dilute Mg-0.50Al-0.71Ca-0.33Mn(wt.%) during hot rolling at two slab temperatures were investigated by electron backscattered diffraction(EbsD) and high resolution transmission electron microscopy(HRTEM). The results show that the development of the rolling microstructures is to first form {10–12} extension twins in the original grains, thereby forming the extension-twinned regions, and then to further form {10–11}-{10–12} double twins and kinks in the extension-twinned regions, and finally to form continuous dynamic recrystallized(continuous DRXed)grains in the double twins and the cross parts of the shear-deformed coarse extension-twinned *** extension twins, double twins and kinks show a decisive effect on the formation of rolling *** number of {10–11}-{10–12} double twins and resultant the continuous DRX process are strongly affected by the rolling slab temperature and the reduction thickness per pass. by optimizing the rolling conditions, texture and microstructures of the multi-pass rolled Mg-Al-Ca-Mn alloy sheets are successfully modified. Although the total alloy content is only 1.5 wt.%, these Mg-Al-Ca-Mn alloy sheets show much higher strength than the commercial Mg-3Al-1 Zn(wt.%)(AZ31b) sheet.

关键词： Mg-Al-Ca-Mn alloy Hot rolling Dynamic recrystallization Texture control Mechanical properties

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模拟信号加密的综述

通信保密 1984年第3期 55-64页

作者： s.C.Kak b.E. 武良 Ph.D.

本文是一篇模拟信号加密问题的评述。种探讨了用秩相关研究置换的方法,描述了应用在置乱体制中的某些置换类型,分析了模拟加密问题以及它的展望。

关键词：置乱变换域模拟加密模拟信号分组加密过取样

无压力室喷油嘴液力研磨对直喷式柴油机混合气形成的影响

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汽车与新动力 1998年第4期 49-59页

作者： Kampmann s Dittus b Mattes P 何庆康

液力研磨(HG)工艺可应用于无压力室喷油嘴(VCO)产品上。当确定VCO喷油嘴液力研磨对增压型高速直喷式柴油机混合气形成的影响,进行了全面的理论计算与试验研究。搞清了液力研磨喷油嘴的喷束特性能满足增压型高速直喷式(HsDI)柴油机混合... 详细信息

液力研磨(HG)工艺可应用于无压力室喷油嘴(VCO)产品上。当确定VCO喷油嘴液力研磨对增压型高速直喷式柴油机混合气形成的影响,进行了全面的理论计算与试验研究。搞清了液力研磨喷油嘴的喷束特性能满足增压型高速直喷式(HsDI)柴油机混合气形成的要求。

关键词：直接喷射柴油机喷油嘴工艺燃烧过程研究

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国际法的阶级方法导论

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北大国际法与比较法评论 2023年第0期17卷 48-77页

作者： b.s.契姆尼冯丽羽印度新德里贾瓦哈拉尔·尼赫鲁大学国际研究学院国际法律研究中心剑桥大学法学院

这篇文章介绍了国际法的阶级方法,挑战了“阶级之死”这一命题,并主张“阶级”范畴的持续性意义。此外,本文证明了“阶级”范畴可以以不消弭性别和种族差异的方式将其纳入其中。鉴于全球社会形态的出现,本文认为跨国资产阶级正在全球化...

这篇文章介绍了国际法的阶级方法,挑战了“阶级之死”这一命题,并主张“阶级”范畴的持续性意义。此外,本文证明了“阶级”范畴可以以不消弭性别和种族差异的方式将其纳入其中。鉴于全球社会形态的出现,本文认为跨国资产阶级正在全球化时代塑造国际法律和国际机构。它呼吁将对当代法律和制度的阶级批判与反抗的理念和实践联系起来,并在此背景下思考了当今新兴的跨国被压迫阶级的国际主义和阶级斗争的意义。文章最后概述了国际法阶级方法的优点。

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