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梯度场核磁共振测井仪电子线路设计

测井技术 2012年第2期36卷 183-187页

作者：于慧俊肖立志 V.Anferov s.anferova 朱万里李新油气资源与探测国家重点实验室中国石油大学北京102249

介绍梯度场核磁共振测井仪控制和采集电路、功率放大电路、Q-转换电路、隔离电路和接收电路等。解决核磁共振测井仪大功率发射和微弱信号检测的技术难题。射频脉冲发射完后,能尽快泄放天线中储存的能量;脉冲发射和能量泄放时可对接收电... 详细信息

介绍梯度场核磁共振测井仪控制和采集电路、功率放大电路、Q-转换电路、隔离电路和接收电路等。解决核磁共振测井仪大功率发射和微弱信号检测的技术难题。射频脉冲发射完后,能尽快泄放天线中储存的能量;脉冲发射和能量泄放时可对接收电路进行高压隔离保护。介绍各关键电路的设计原理,并利用所设计的电子线路和自制核磁共振测井仪探头,在实验室条件下对硫酸铜水溶液进行测量,得到满意结果。该电子线路已成功应用于自制梯度场核磁共振测井仪样机,对随钻核磁共振测井仪和井下核磁共振流体分析同样具有重要的参考价值。

关键词：核磁共振测井仪大功率发射微弱信号检测能量泄放电子线路设计

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核磁共振测井仪低噪声模拟接收电路设计

测井技术 2013年第2期37卷 183-186页

作者：于慧俊肖立志朱万里李新 s.anferova V.Anferov 油气资源与探测国家重点实验室中国石油大学北京102249

设计了一种用于核磁共振测井仪的低噪声模拟接收电路。第1级放大为自主构建的仪器用放大器,其增益为52dB,选用最佳源电阻与天线谐振阻抗相近的超低噪声宽带运放LMH6626保证电路的低噪声性能。对第1级放大器的噪声性能进行了理论分析,其... 详细信息

设计了一种用于核磁共振测井仪的低噪声模拟接收电路。第1级放大为自主构建的仪器用放大器,其增益为52dB,选用最佳源电阻与天线谐振阻抗相近的超低噪声宽带运放LMH6626保证电路的低噪声性能。对第1级放大器的噪声性能进行了理论分析,其噪声系数为1.45。实验测试结果表明,电路最大增益为112dB,频率范围为400kHz～1MHz,可对核磁共振信号进行低噪声放大,并已成功应用于核磁共振测井仪实验室样机中。

关键词：核磁共振测井仪低噪声模拟接收电路放大器噪声性能电路设计

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基于FPGA的核磁共振测井仪控制逻辑设计

波谱学杂志 2012年第2期29卷 201-208页

作者：于慧俊肖立志 V. Anferov s. anferova 朱万里刘化冰郭葆鑫油气资源与探测国家重点实验室中国石油大学(北京) 北京102249 中国石油集团测井有限公司技术中心陕西西安710021

核磁共振(NMR)测井仪以CPMG脉冲序列为测量基础,按照CPMG脉冲序列的时序要求完成大功率射频脉冲的发射和微弱回波信号的接收,在脉冲发射完成后快速泄放天线中储存的能量.该文介绍一种基于现场可编程门阵列(FPGA)的NMR测井仪控制逻辑和... 详细信息

核磁共振(NMR)测井仪以CPMG脉冲序列为测量基础,按照CPMG脉冲序列的时序要求完成大功率射频脉冲的发射和微弱回波信号的接收,在脉冲发射完成后快速泄放天线中储存的能量.该文介绍一种基于现场可编程门阵列(FPGA)的NMR测井仪控制逻辑和典型脉冲序列,详细说明在CPMG脉冲序列下FPGA的工作时序和流程;讨论NMR测井仪发射电路、Q-转换电路和隔离电路的控制原理和时序要求,给出各电路的控制逻辑仿真结果;最后,利用所设计的控制逻辑和自制NMR测井仪探头,在实验室条件下对水溶液进行了测量,得到满意的结果.

关键词：核磁共振测井仪 CPMG 脉冲序列 FPGA

孔隙介质中孔隙空间尺寸与磁化系数差异相关性研究

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孔隙介质中孔隙空间尺寸与磁化系数差异相关性研究

Revisiting cerebral endothelial cells in Alzheimer’s disease

第十七届全国波谱学学术会议

作者：刘化冰肖立志李新于慧俊张宗富宗芳容 V.Anferovv s.anferova 中国石油大学(北京)油气资源与探测国家重点实验室

＜正＞磁化系数是一种重要的物理性质,可用于表征物质材料中的特殊元素含量和被磁化的难易程度。在自然或人造的孔隙介质中,由于固体骨架与饱含在孔隙空间内部的液体之间磁化系数存在差异,在孔隙中会形成一个与空间位置有关的内部梯度...

＜正＞磁化系数是一种重要的物理性质,可用于表征物质材料中的特殊元素含量和被磁化的难易程度。在自然或人造的孔隙介质中,由于固体骨架与饱含在孔隙空间内部的液体之间磁化系数存在差异,在孔隙中会形成一个与空间位置有关的内部梯度磁场。通过测量分析该场的分布与大小可用于研究物质磁化系数的差异。

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Complementary roles of glial cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2917-2918页

作者： Leyre Ayerra Maria s.Aymerich Universidad de Navarra Facultad de CienciasDepartamento de Bioquímica y GenéticaPamplonaSpain CIMA-Universidad de Navarra PamplonaSpain IdisNA Instituto de Investigación Sanitaria de NavarraPamplonaSpain

Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic *** has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be *** leukocyte antigen.

关键词： inflammation leukocyte generating

A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant

Deciphering the mechanobiology of microglia in traumatic brain injury with advanced microsystems

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Neural Regeneration Research 2025年第8期20卷 2304-2306页

作者： Anthony Procès sylvain Gabriele Univ.Grenoble Alpes InsermU1216Grenoble Institut des NeurosciencesGrenobleFrance Mechanobiology&Biomaterials Group CIRMAPResearch Institute for BiosciencesUniversity of MonsMonsBelgium

Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results from a mechanical insult to the brain,leading to neuronal and axonal damage and subsequently causing a secondary *** minutes ... 详细信息

关键词： traumatic injury damage