检索结果-南通市图书馆

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

钛铝金属间化合物激光点火燃烧行为及机理

材料工程 2024年第5期52卷 1-16页

作者：吴明宇弭光宝李培杰隋楠董富礼中国航发北京航空材料研究院先进钛合金航空科技重点实验室北京100095 清华大学新材料国际研发中心北京100084

采用激光氧浓度实验方法结合超高温红外测温仪和高速摄像机原位观察、扫描电子显微分析和X射线衍射分析等方法,对钛铝金属间化合物(TiAl合金)的点火燃烧行为进行研究,揭示燃烧过程熔体的形成与运动规律、氧化物类型和结构特征,进而探讨... 详细信息

采用激光氧浓度实验方法结合超高温红外测温仪和高速摄像机原位观察、扫描电子显微分析和X射线衍射分析等方法,对钛铝金属间化合物(TiAl合金)的点火燃烧行为进行研究,揭示燃烧过程熔体的形成与运动规律、氧化物类型和结构特征,进而探讨燃烧机理。结果表明:TiAl合金发生起燃及持续燃烧的激光功率和氧浓度临界条件分别遵循抛物线规律和抛物线+直线规律,且显著高于近α型高温钛合金,即具有更好的阻燃性能;TiAl合金的起燃温度高于基体相熔点,起燃时基体部分熔化,导致Al元素由内氧化机制转变为外氧化机制;扩展燃烧阶段形成的氧化物由内侧到燃烧表面依次为Al_(2)O_(3),Al_(2)Ti_7O_(15),Al_(2)TiO_(5)和Al_(6)Ti_(2)O_(13)相,其中熔凝区内形成的连续网状Al_(2)O_(3)层能够阻碍熔体运动,燃烧区内形成的Ti-Al-O三元相通过降低内层Al_(2)O_(3)的分解压提升Al_(2)O_(3)保护层的稳定性,使TiAl合金具有良好的阻燃性能。

关键词： TiAl合金激光点火氧化燃烧产物燃烧机理起燃温度

Burning products of TA15 titanium alloy by friction oxygen concentration method

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2018年第11期37卷 952-960页

作者： nan sui Guang-Bao Mi Meng-Qi Yan Jing-Xia Cao Xu Huang Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys AECC Beijing Institute of Aeronautical Materials

The microstructural characteristics, elemental distribution law and microscopic formation mechanism of the burning products of TA15 titanium alloy were investigated by friction oxygen concentration method, associated with in situ observation, X-ray diffraction(XRD),scanning electron microscopy(SEM) and energy-dispersive spectroscopy(EDS) analyses, providing the thoughts to improve fireproof property. The results show that, when the friction contact pressure(p) is 0.20 MPa and oxygen concentration of premixed air flow(c) is 60 vol%, TA15 titanium alloy produces violent sparks and presents dazzling white light during combustion. The generated products after burning are mainly TiOand small amount of AlOoxides. Four distinct zones form from the combustion surface to the alloy matrix, and they are in the sequence of combustion zone, fusion zone, heat-affected zone and transition zone. Further, combustion zone is composed of TiOand A1203 compounds, containing obvious cracks. In the fusion zone, discontinuous oxygenrich Al-based solid solution forms, and the elemental distribution has strong volatility. In the heat-affected zone,there are abundant of Ti-based solid solution and small amount of Al-and Mo-based solid solution. Transition zone is made of lamellar structure. Two technical approaches are given to prevent oxygen diffusion inside the reaction zone and reaction-affected zone. On the one hand,the content of Al is designed as the upper limit of alloy composition; on the other hand, fireproof coatings are deposited on the surface of the alloy.

关键词： Friction oxygen concentration method TA15 titanium alloy Burning products Microstructure Titanium fire

Morphine pre-exposure facilitates reinstatement but attenuates retention of morphine-induced place preference

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2010年第12期5卷 942-947页

作者： Dongmei Wang Xigeng Zheng Yonghui Li Xiaoyan Yang nan sui Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101 China

BACKGROUND： Drug-associated conditioned stimuli are a key factor to induce morphine relapse. To date, limited evidence is available regarding the impact of drug history on propensity or vulnerability to relapse after long-term abstinence. OBJECTIVE： To determine the effect of morphine pre-exposure on acquisition, maintenance and reinstatement of morphine-induced conditioned place preference （CPP） in rats. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Laboratory of Behavior Pharmacology, Institute of Psychology, the Chinese Academy of Sciences, from March to September, 2006. MATERIALS： Morphine hydrochloride was purchased from Qinghai Pharmaceutical, China; CPP software was designed and developed by Taiji Software Company, Beijing, China. METHODS： A total of 64 Sprague Dawley rats were randomly assigned to eight groups （n = 8）. Four morphine pretreatment regimens were used （subcutaneous injections, twice daily for 5 consecutive days and a total of 10 times）：（1）＂intensive＂（morphine injections with doses escalating from 10 to 60 mg/kg; （2）＂moderate＂（one morphine injection at 5 mg/kg dose and one saline injection at 1 mL/kg daily for 5 days）; and （3）＂single＂（nine saline injections at 1 mL/kg followed by one morphine injection at 5 mg/kg; （4） control （ten saline injections at 1 mL/kg）. At 5 days after morphine pretreatment, animals were divided into two subgroups that underwent morphine conditioned or saline conditioned training. The test for acquisition of CPP was performed 24 hours after CPP training. The retention of morphine CPP was measured by repeated tests performed weekly for 1 month after the initial test of place preference. After extinction by pairing each chamber with saline, the reinstatement of place preference by low doses of morphine （0.05, 0.15, 0.45 mg/kg） was tested. MAIN OUTCOME MEASURES： Acquisition, maintenance, and recovery response of CPP behavior. RESULTS： The acquisition magnitude of morphine-induced CPP was not affected by prior morphine ex

关键词： conditioned place preference morphine reinstatement drug history addiction relapse neuropharmacology neural regeneration

Enhancement of Aggression Induced by Isolation Rearing is Associated with a Lack of Central Serotonin

在线全文

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2019年第5期35卷 841-852页

作者： Yiqiong Liu Yunong Sun Xiaoyan Zhao Ji-Young Kim Lu Luo Qian Wang Xiaolu Meng Yonghui Li nan sui Zhou-Feng Chen Chuxiong Pan Liang Li Yan Zhang State Key Laboratory of Membrane Biology College of Life Sciences Peking University Beijing 100871 China Department of Anesthesiology Beijing Tongren Hospital Capital Medical University Beijing 100005 China Department of Anesthesiology Department of Psychiatry Department of Developmental Biology Center for the Study of Itch Washington University School of Medicine Saint Louis MO 63110 USA School of Psychological and Cognitive Sciences Beijing Key Laboratory of Behavior and Mental Health Peking University Beijing 100871 China Beijing Institute for Brain Disorders Beijing 100069 China Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Hendrix College Conway AR 72032 USA PKU-IDG/McGovern Institute for Brain Research Beijing 100871 China

Isolation rearing(IR) enhances aggressive behavior, and the central serotonin(5-hydroxytryptamine,5-HT) system has been linked to IR-induced aggression.However, whether the alteration of central serotonin is the cause or consequence of enhanced aggression is still unknown. In the present study, using mice deficient in central serotonin Tph2-/-and Lmx1 b-/-, we examined the association between central serotonin and aggression with or without social isolation. We demonstrated that central serotonergic neurons are critical for the enhanced aggression after IR. 5-HT depletion in wild-type mice increased aggression. On the other hand, application of 5-HT in Lmx1 b-/-mice inhibited the enhancement of aggression under social isolation conditions. Dopamine was downregulated in Lmx1 b-/-mice. Similar to 5-HT, L-DOPA decreased aggression in Lmx1 b-/-mice. Our results linkthe serotoninergic system directly to aggression and this may have clinical implications for aggression-related human conditions.

关键词： 5-HT Aggression Social isolation Dopamine Lmx1b

Parkin promotes proteasomal degradation of p62： implication of selective vulnerability of neuronal cells in the pathogenesis of Parkinson＇s disease

在线全文

学校读者我要写书评

暂无评论

Protein & Cell 2016年第2期7卷 114-129页

作者： Pingping Song Shanshan Li Hao Wu Ruize Gao Guanhua Rao Dongmei Wang Ziheng Chen Biao Ma Hongxia Wang nan sui Haiteng Deng Zhuohua Zhang Tieshan Tang Zheng Tan Zehan Han Tieyuan Lu Yushan Zhu Quan Chen State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratory of Protein Science College of Life SciencesNankai University Tianjin 300071 China State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of SciencesBeijing 100101 China Institute of Psychology Chinese Academy of Sciences Beijing 100101 China College of Life Sciences Tsinghua University Beijing 100084 China State Key Laboratory of Medical Genetics Xiangya Medical School Central South University Changsha 410078 China Department of Health and Sports Science Tianjin University of Sport Tianjin 300381 China

Mutations or inactivation of parkin, an E3 ubiquitin ligase, are associated with familial form or sporadic Parkinson＇s disease （PD）, respectively, which manifested with the selective vulnerability of neuronal ceils in substantia nigra （SN） and striatum （STR） regions. However, the underlying molecular mechanism linking parkin with the etiology of PD remains elusive. Here we report that p62, a critical regulator for protein quality control, inclusion body formation, selective autophagy and diverse signaling pathways, is a new substrate of parkin. P62 levels were increased in the SN and STR regions, but not in other brain regions in parkin knockout mice. Parkin directly interacts with and ubiquitinates p62 at the K13 to promote proteasomal degradation of p62 even in the absence of ATG5. Pathogenic mutations, knockdown of parkin or mutation of p62 at K13 prevented the degradation of p62. We further showed that parkin deficiency mice have pronounced loss of tyrosine hydroxylase positive neurons and have worse performance in motor test when treated with 6-hydroxydopamine hydrochloride in aged mice. These results suggest that, in addition to their critical role in regulating autophagy, p62 are subjected to parkin mediated proteasomal degradation and implicate that the dysregulation of parkin/p62 axis may involve in the selective vulnerability of neuronal cells during the onset of PD pathogenesis.

关键词： parkin sequestosome1/p62 ubiquitin,substantia nigra

Medium spiny neurons of the anterior dorsomedial striatum(aDMS) mediate cognitive flexibility in a cell-type dependent manner

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Medium spiny neurons of the anterior dorsomedial striatum(aD...

Gnas methylation in the basolateral amygdala regulates reconsolidation of morphine associated memory in rats

第六届心理健康学术年会

作者： Xingyue Wang Yanhua Qiao nan sui Jing Liang Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences

The deficits in cognitive flexibility are commonly observed in many mental disorders, including Parkinson’s disease(PD), schizophrenia, and drug addiction. Although striatum has been implicated in regulating flexible behaviors, the exact subregion which associate in these behaviors is still unclear in this heterogeneous brain region.Among the striatum subareas, the anterior part of the dorsomedial striatum(aDMS) is reported to play particular role in the pathology of these disorders with cognitive inflexibility. The aDMS mainly consists of two types of neurons(D1R-and D2R-MSNs). However, the exact role of these neurons and their projections in cognitive flexibility are still unclear.To clarify the specific function of aDMS projections in cognitive flexibility, we used optogenetic approach to clarify the roles of D1R direct and D2R indirect pathways in the aDMS in mediating cognitive flexibility with a cre-strategy.The activities in the medialdorsal thalamus(MD),a downstream region of the striatum, were identified in functional pattern by using immonochemicohistory following light-stimulation-modulated behaviors.We found seversal observations. Activation of D1R-MSNs in aDMS impaired reversal learning and behavioral extinction, while activation of D2R-MSNs in this brain area facilitated the strategy reverse and extinction. Accordingly, the neuronal activity in MD thalamus,was down-regulated or up-regulated,with disruption or facilitation of reversal performance.

关键词： Anterior dorsomedial striatum behavioral flexibility optogenetics medium spiny neurons dopamine receptors

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Gnas methylation in the basolateral amygdala regulates recon...

A model of depression in tree shrews:learned helplessness

第六届心理健康学术年会

作者： Jianjun Zhang Peng Liu Fengze Jiang nan sui CAS Key Laboratory of Mental Health Institute of Psychology Department of Psychology University of Chinese Academy of Sciences

Recently, we and other laboratories reported that DNA methyltransferases(Dnmts)were involved in the reconsolidation of addiction related memory, but how DNA methylation regulates reconsolidation of opiate reward memory remain to be found. Here, using morphine induced conditioned place preference(mCPP) in rats, we showed that Dnmts inhibition in basolateral amygdala(BLA), but not in central amygdala or nucleus accumbens, disrupted reconsolidation of morphine reward memory. Moreover, the disruption effects were retrieval-and time-window-dependent. Concordant with this, the mRNA levels of Dnmt 3 a and Dnmt 3 b but not Dnmt 1 in the BLA were significantly upregulated since one hour after memory retrieval. Thus, we further explored the target genes of DNA methylation in the BLA at one hour after retrieval and found 75 differentially methylated regions. Then, we verified the DNA methylation and the roles of three genes(Pik3 r1, Gnas and Sox10) whose promoter were hypermethylated in reconsolidation.The DNA methylation level of these genes were upregulated and the mRNA levels were downregulated. Intra-BLA injection of the PI3 K agonist 740 Y-P immediately after memory retrieval impaired the reconsolidation, and BLA-specific overexpression of Gnas significantly disrupted the reconsolidation. However, overexpression of Sox10 in BLA did not affect this process. These data demonstrated that DNA methylation in BLA, mediated by Dnmt 3 a and/or Dnmt 3 b, regulated reconsolidation of morphine reward memory via hypermethylation of Gnas promotor.

关键词： DNA methylation reconsolidation morphine basolateral amygdala Dnmts Gnas

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

A model of depression in tree shrews:learned helplessness

基于大肠主津理论助阳通便膏对便秘模型小鼠结肠组织VIP-CAMP-PKA-AQP3通路的影响

中国神经科学学会第十届全国学术会议

作者： Xiao-Lu MENG Ning ZHU Chun-Lu LI nan sui Key Laboratory of Mental Health Institute of PsychologyChinese Academy of Sciences University of Chinese Academy of Sciences

Objective We are developing a model of depression in tree shrews,a newly recognized nonhuman primate,using learned helplessness paradigm.Learned helplessness（LH） is widely used for screening new treat targets and the pathophysiological mechanism as an animal model of depression.The present study was to test the face and predict validity of this model.Method Male tree shrews were subjected to 40 footshocks for 7 days,uncontrollable and inescapable（UI） or controllable and escapable（CE）.Then fluoxetine（15 mg/kg） was orally administrated for 2 weeks.On the day after stress and the day after drug treatment,depression-like behaviors were determined,including escape latency,escape failure and the breakpoint for 5%sucrose under a progressive-ratio（PR） schedule.Results One third of tree shrews subjected to UI footshocks showed increase number of escape failure,prolonged escape latency and reduced breakpoint for 5%sucrose.Fluoxetine treatment reduced the number of escape failure and shortened the escape latency,but didn’t affect the breakpoint for sucrose.Conclusion The learned helplessness in tree shrews shows some depression-like behaviors with individual difference,some of which reversed by a typical antidepressant.Although it requires further validation,the learned helplessness model in tree shrews is a promising primate model for research on the etiology and pathophysiology of depression.

关键词： tree shrews learned helplessness face validity predictive validity

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

中华中医药学刊 2022年第5期40卷 147-151,277-278页

作者：王璐隋楠辽宁中医药大学辽宁沈阳110847 辽宁中医药大学附属第三医院辽宁沈阳110003

目的观察助阳通便膏对便秘模型小鼠结肠组织VIP-CAMP-PKA-AQP3信号通路的影响。方法将作为实验对象的96只雄性BALB/C小鼠随机分成4组,即正常对照组、模型对照组、助阳通便膏组以及麻仁软胶囊组,24只/组。造模予以复方地芬诺酯片混悬液... 详细信息

目的观察助阳通便膏对便秘模型小鼠结肠组织VIP-CAMP-PKA-AQP3信号通路的影响。方法将作为实验对象的96只雄性BALB/C小鼠随机分成4组,即正常对照组、模型对照组、助阳通便膏组以及麻仁软胶囊组,24只/组。造模予以复方地芬诺酯片混悬液灌胃的方法进行。在模型建立后,每组小鼠对应给予蒸馏水、助阳通便膏及麻仁软胶囊连续行2周灌胃,结束后取材,应用不同方法——RT-PCR法、Wester Blot法及免疫荧光双标法,观测各组小鼠的结肠组织中血管活性肠肽(VIP)、环磷酸腺苷(CAMP)、蛋白激酶(PKA)和水通道蛋白3(AQP3)的表达。结果通过RT-PCR的方法发现,助阳通便膏组VIP、AQP3mRNA表达水平显著高于模型对照组(P0.05)。通过免疫荧光双标的方法发现,助阳通便膏组VIP-AQP3、CAMP-PKA免疫荧光双标表达双阳性细胞数均显著高于模型对照组(P0.05)。结论助阳通便膏治疗慢传输型便秘的作用机制可能是通过提高结肠组织中VIP-CAMP-PKA-AQP3通路表达水平来实现的。

关键词：助阳通便膏功能性便秘实验研究 VIP-CAMP-PKA-AQP3通路