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Friction and wear behaviors of a gradient nano-grained AISI 316L stainless steel under dry and oil-lubricated conditions

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Journal of Materials Science & Technology 2018年第10期34卷 1835-1842页

作者： P.F. Wang z. han Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

A gradient nano-grained （GNG） surface layer was fabricated on an AIS1316L stainless steel （SS） by using the surface mechanical rolling treatment （SMRT）. Reciprocating dry and oil-lubricated sliding tests of the GNG 316L SS in air at room temperature were conducted in comparison with the coarse-grained （CG） counterpart. Worn surface morphologies and subsurface microstructures were investigated for both 316L SS samples. 316L SS with a GNG surface layer shows a significantly improved wear resistance, especially under oil-lubricated condition. The notably wear resistance enhancement of the GNG 316L SS is attributed to the GNG surface layer with high strain accommodation ability and high hardness, which can reduce the wear volume in the running-in stage effectively.

关键词： Austenitic stainless steel Gradient nano-grained surface layer Friction and wear Running-in

Topological phases of a non-Hermitian coupled SSH ladder

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Chinese Physics B 2019年第10期28卷 269-273页

作者： J S Liu Y z han C S Liu Hebei Key Laboratory of Microstructural Material Physics School of Science Yanshan University

We study topological phases of a non-Hermitian coupled Su-Schrieffer-Heeger(SSH) ladder. The model originates from the brick-wall lattices in the two-row limit. The Hamiltonian can be brought into block off-diagonal form and the winding number can be defined with the determine of the block off-diagonal matrix. We find the determine of the offdiagonal matrix has nothing to do with the interleg hopping of the ladder. So the topological phases of the model are the same as those of the chains. Further numerical simulations verify the analysis.

关键词： topological phase non-Hermitian Su-Schrieffer-Heeger(SSH) ladder winding number

A new way to construct topological invariants of non-Hermitian systems with the non-Hermitian skin effect

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Chinese Physics B 2020年第1期29卷 119-123页

作者： J S Liu Y z han C S Liu Hebei Key Laboratory of Microstructural Material Physics School of ScienceYanshan UniversityQinhuangdao 066004China

The non-Hermitian skin effect breaks the conventional bulk–boundary correspondence and leads to non-Bloch topological *** by the fact that the topological protected zero modes are immune to perturbations,we construct a partner of a non-Hermitian system by getting rid of the non-Hermitian skin *** adjusting the imbalance hopping,we find that the existence of zero-energy boundary states still dictate the bulk topological invariants based on the band-theory *** non-Hermitian Su–Schrieffer–Heeger(SSH)models are used to illuminate the ***,we obtain the winding numbers in analytical form without the introduction of the generalized Brillouin *** work gives an alternative method to calculate the topological invariants of non-Hermitian systems.

关键词： non-Hermitian skin effect Su–Schrieffer–Heeger(SSH)model bulk–boundary correspondence topological invariant

R & D OF CAST SUPERALLOYS AND PROCESSING FOR GAS TURBINE BLADES IN BIAM

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 457-463页

作者： Y.F. han and R.z. Chen(Institute of Aeronautical Materials, Beijing 100095,China ) Beijing Inst of Aeronautical Materials Beijing China

Research and development of cast superalloys and processing for turbine blades in BIAM during the last 35 years have been reviewed briefly in this paper.

关键词： cast nickel base superalloy turbine blade ceramic core shell Mold

Proteome-wide alterations in an industrial clavulanic acid producing strain of Streptomyces clavuligerus

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Synthetic and Systems Biotechnology 2017年第1期2卷 39-48页

作者： EserÜnsaldı Aslıhan Kurt-Kızıldogan Birgit Voigt Dorte Becher Gülay Ozcengiz Department of Biological Sciences Middle East Technical University06800AnkaraTurkey Department of Agricultural Biotechnology Ondokuz Mayıs University55139SamsunTurkey Institute of Microbiology Ernst-Moritz-Arndt-University of GreifswaldD-17487GreifswaldGermany

The usefulness of genetic/metabolic engineering for further improvement of industrial strains is subject of discussion because of the general lack of knowledge on genetic alterations introduced by iterative cycles of random mutagenesis in such *** industrial clavulanic acid(CA)-overproducer Streptomyces clavuligerus DEPA was assessed to understand proteome-wide changes that have occurred in a local industrial CA overproducer developed through succesive mutagenesis *** proteins that could be identified corresponded to 33 distinct ORFs for underrepresented ones and 60 ORFs for overrepresented *** CA biosynthetic enzymes were overrepresented in *** DEPA;carboxyethylarginine synthase(Ceas2),clavaldehyde dehydrogenase(Car)and carboxyethyl-arginine betalactam-synthase(Bls2)whereas the enzymes of two other secondary metabolites were underrepresented along with two important global regulators[two-component system(TCS)response regulator(SCLAV_2102)and TetR-family transcriptional regulator(SCLAV_3146)]that might be related with CA production and/or differentiation.g-butyrolactone biosynthetic protein AvaA2 was 2.6 fold underrepresented in *** *** levels of two glycolytic enzymes,2,3-bisphosphoglycerate-dependent phosphoglycerate mutase and phosophoglycerate kinase were found decreased while those of dihydrolipoyl dehydrogenase(E3)and isocitrate dehydrogenase,with two isoforms were found as significantly increased.A decrease of amino acid metabolism,methionine biosynthesis in particular,as well as S-adenosylmethionine synthetase appeared as one of the prominent mechanisms of success of *** DEPA strain as a prolific producer of *** levels of two enzymes of shikimate pathway that leads to the production of aromatic amino acids and aromatic secondary metabolites were also *** of the overrepresented stress proteins in *** DEPA included polynucleotide phosphorylase/polyadenylase(PNPase),ATP

关键词： Clavulanic acid Streptomyces clavuligerus Industrial strain Proteomics 2DE MALDI-TOF/MS

Characters of evoked burst and it’s current mechanism in CCD model

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Characters of evoked burst and it’s current mechanism in CC...

Activity of the Lenglongling fault system and seismotectonics of the 2016 MS6.4 Menyuan earthquake

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： Victor z han Oregon Health Sciences University BeavertonOR 97006USA

＜正＞Objective Lots of neuropathic pain models were made during decades of investigations,in which spontaneous discharge originated from dorsal root ganglion（DRG） were regarded as a key point for development of various abnormal pain *** idea of that if any firing patterns could be identified to be related to certain abnormal pain behavior has not been concerned up to *** present study is to explore what’s kind of characters of evoked burst（EB）,a newly observed firing pattern *** whether it is related to the mechanical allodynia exhibited on a chronic compression of DRG（CCD） model,which mimicking the clinical intervertebral foramen stenosis or proceeding of intervertebral disc. Methods On a CCD model,the von-Frey stimulation were used to observe the mechanical allodynia,in vivo sharpelectrode or in vitro patch-clamp recording were carried on to record the activity from DRG *** interruptions were applied to see the effect on EB as well as the underlying current ***（1） After CCD model,the DRG soma became hyperexcitable with various firing pattern.（2） On the animal with obvious mechanical allodynia,a kind of evoked burst（EB）,which means a periphery input spike followed by the somatic burst firing,was identified on Aβtype of neurons with a significantly increased percentage of 34%（15/44） comparing to those in normal（10%,1/9）,either at the resting membrane level or on a depolarized potential.（3） The EB has the following character:it’s exist relys on the complement of the periphery input,on the other words,it was evoked by periphery stimulation,either from electrical stimulation of the sciatic nerve or the stimulation of their natural receptive *** the shape of the first spike in the burst,the EB could be identified from those of spontaneous burst（SB）,namely,EB has a rapid-onset kinetics（with a rising speed of 50.75±6.46V/s,n=9） while SB has a prepotential phase at the foot of first spike（with a rising speed of 2.34±0.92V/

关键词： neuropathic pain dorsal root ganglion mechanical allodynia pain signal periphery analgesia

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Science China Earth Sciences 2017年第5期60卷 929-942页

作者： GUO Peng han zhuJun AN YanFen JIANG WenLiang MAO zeBin FENG Wei Key Laboratory of Active Tectonics and Volcano Institute of Geology China Earthquake Administration Beijing 100029 China Key Laboratory of Crustal Dynamics Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China China University of Geosciences School of Earth Sciences and Resources Beijing 100083 China Institute of Earthquake Science China Earthquake Administration Beijing 100036 China China Earthquake Networks Center Beijing 100045 China

The MS6.4 Menyuan earthquake occurred on the northern side of the Lenglongling fault(LLLF) in the mid-western of the Qilian-Haiyuan fault zone on January 21, 2016. The earthquake epicenter was distant from the Minle-Damaying and Huangcheng-Shuangta faults, eastern of the Northern Qilian Shan fault zone. A near northwest-striking rupture plane intersects the two faults at a certain angle. The focal mechanism solution shows that this was a thrust-type earthquake, slightly different from the strike-slip movement with a thrust component of the LLLF. Field geological mapping, tectonic geomorphology analysis, trench excavation and 14 C dating reveal that(1) the LLLF has been obviously active since the Holocene, and may behave with characteristic slip behavior and produce M_W7.3–7.5 earthquakes;(2) the LLLF appears as a flower structure in terms of structure style, and dips NNE at a steep angle; and(3) the most recent earthquake event occurred after 1815–1065 a BP. An associated fault, the Northern Lenglongling fault(NLLLF), is located at the northwestern end of the LLLF. Consequently, the NLLLF was continually subject to tectonic pushing effects from the left-lateral shear at the end of the LLLF, and, accordingly, it bent and rotated outward ***, the fault deviated from the dominant rupture azimuth and activity weakened. In the late Quaternary, it behaved as a thrust fault with no obvious deformation at the surface. This is indicated by the arc shape, with a micro-protrusion northeastward,and no geologic or geomorphic signs of surface rupturing since the late Quaternary. However, such faults could still rupture at depth, producing moderate-strong earthquakes. The geometric and kinematic properties of the NLLLF are in good agreement with the occurrence and kinematic properties of nodal plane 2, and with the distribution characteristics of the aftershocks and seismic intensity. Therefore, the NLLLF is a more suitable seismogenic structure for the MS 6.

关键词： MS6 4 Mengyuan earthquake Seismogenic structure Tectonic environment Lenglongling fault Northern Lenglongling fault

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睡眠、梦境的机制及其与学习记忆的关系

生理科学进展 2013年第6期44卷 409-414页

作者：韩中胜史均翰 Center for Integrative Brain Research Seattle Children's Research Institute 渭南师范学院睡眠梦象研究中心渭南714000

睡眠是动物界的共同生理特征之一,表现为可逆性意识状态丧失。在人类每日的睡眠时间随年龄的增长而递减,总睡眠时间在一个人大约占去一生时间的三分之一。人的睡眠有很明显的周期性和时相性,其过程主要由体内固有的生物钟直接控制,但也... 详细信息

睡眠是动物界的共同生理特征之一,表现为可逆性意识状态丧失。在人类每日的睡眠时间随年龄的增长而递减,总睡眠时间在一个人大约占去一生时间的三分之一。人的睡眠有很明显的周期性和时相性,其过程主要由体内固有的生物钟直接控制,但也受外界自然环境特别是光线强弱持续变化的调节。睡眠的生物学机理仍在研究探讨之中。梦境是伴随睡眠的一种神经心理活动过程,人人都有体验,大约和睡眠一样历史久远。但对其产生原理和生物学意义也是众说纷纭,没有共识。近年来的研究结果表明,睡眠的核心功能之一是进一步加工和处理当日大脑所接受的新信息,并将其选择性地转化为可长期保存的信息,储存在相应的大脑皮层功能区,即所谓的记忆信息巩固过程。本文简介睡眠和梦境这一对截然不同却又难以分开的生命现象的神经生理学基础、功能意义以及这方面的研究进展,并重点介绍睡眠期间所发生的学习记忆活动的研究进展。

关键词：睡眠梦境记忆信息巩固

孤独症患者的偏才和获得性偏才现象及其神经生物学机理

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生理学报 2018年第2期70卷 201-210页

作者：张宇韩中胜山西医科大学生理学系太原030001 美国西雅图儿童研究所综合脑科学研究中心西雅图98101

孤独症是一种病因复杂、临床表现多样、与早期发育密切相关的儿科常见病,严重影响患者的学习和日常生活能力,但部分患者却伴有某种超常的技巧或才能,即所谓"孤独偏才"现象。与此相关的另一罕见现象是,某些人在中枢神经系统受伤后也表现... 详细信息

孤独症是一种病因复杂、临床表现多样、与早期发育密切相关的儿科常见病,严重影响患者的学习和日常生活能力,但部分患者却伴有某种超常的技巧或才能,即所谓"孤独偏才"现象。与此相关的另一罕见现象是,某些人在中枢神经系统受伤后也表现出某种特殊的技巧或才能,即所谓"获得性偏才"现象。研究资料表明,这两类偏才的神经生物学变化原理有许多共同之处。本文简介这两类偏才现象,并进一步分析其神经生物学原理,以帮助人们对这些特殊大脑功能活动的了解。

关键词：孤独症谱系障碍孤独偏才获得性偏才神经生物学原理