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模拟界面换热系数和密度对热溶质对流影响

材料科学与工艺 2005年第1期13卷 94-98页

作者：李强莫春立康秀红李殿中钱百年沈阳工业大学材料科学与工程学院辽宁沈阳110023 中国科学院金属研究所辽宁沈阳110016

为了能够更好地控制凝固过程热和溶质的传输,以二元合金为例,研究了在单边散热条件下,不同界面换热系数和密度对热溶质对流的影响.研究表明:当材料密度一定时,随着界面换热系数的提高,沿散热方向上的温度梯度增大,热溶质对流的效果增强... 详细信息

为了能够更好地控制凝固过程热和溶质的传输,以二元合金为例,研究了在单边散热条件下,不同界面换热系数和密度对热溶质对流的影响.研究表明:当材料密度一定时,随着界面换热系数的提高,沿散热方向上的温度梯度增大,热溶质对流的效果增强;当界面换热系数为1000W/(m2·K)时,在凝固初期铸件底部出现涡流现象;在界面换热系数不变的情况下,随着材料密度的增加,铸件内液体金属的热溶质对流效应减弱.

关键词：热溶质对流凝固界面换热系数数值模拟

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用FPGA提高△-∑ADC的配置能力

中国集成电路 2017年第1期26卷 40-41,65页

作者：钱柏年深圳市鼎阳科技有限公司深圳518050

在实际的△-∑ADC使用过程中,存在一些对芯片功能进行扩充和优化的需求。从芯片的基本功能出发,利用FPGA可编程特点,对ADC的输出数据进行处理,从而提高系统性能和灵活配置能力,将这方法应用于产品开发实际中,取得了理想的效果。

关键词： △-∑ADC FPGA 数字滤波器

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测量电路中的共地干扰问题

中国集成电路 2017年第3期26卷 76-78页

作者：钱柏年深圳鼎阳科技有限公司深圳518050

结合产品开发中的实际案例,分析了测试测量电路中的共地干扰的常见现象,产生原因,以及在电路设计和PCB布线中如何避免和解决此类问题的一些思路。为此类问题的研究,尤其是实际的产品开发,提供一些借鉴。

关键词：共地干扰

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高强铝合金2219液化裂纹研究

机械工程材料 2005年第7期29卷 14-16,34页

作者：杨成刚钱百年国旭明中国科学院金属研究所辽宁沈阳110016

用热塑性试验评定2219铝合金的液化裂纹敏感性,利用扫描电镜对热塑性试样断口进行了分析。结果发现:α(Al)-CuAl2离异共晶熔点高于α(Al)-CuAl2共晶;加热过程中α(Al)-CuAl2离异共晶后熔化,冷却过程中离异共晶先凝固结晶,因此2219铝合... 详细信息

用热塑性试验评定2219铝合金的液化裂纹敏感性,利用扫描电镜对热塑性试样断口进行了分析。结果发现:α(Al)-CuAl2离异共晶熔点高于α(Al)-CuAl2共晶;加热过程中α(Al)-CuAl2离异共晶后熔化,冷却过程中离异共晶先凝固结晶,因此2219铝合金脆性温度区间较窄;α(Al)-CuAl2离异共晶的凝固结晶使合金在高温下迅速恢复强度和塑性,使2219铝合金液化裂纹敏感性低,焊接性好。

关键词：热塑性试验脆性温度区间 α(Al)-CuAl2离异共晶

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X80管线钢焊接粗晶区组织与韧性的研究

上海交通大学学报 2003年第12期37卷 1854-1857页

作者：薛小怀周昀钱百年李晶丽楼松年上海交通大学材料科学与工程学院上海200030 中国科学院金属研究所沈阳110016

X80钢经焊接热模拟后粗晶区组织明显粗化,韧性显著下降.低碳时在粗晶区中的贝氏体铁素体板条间形成的硬而脆的Fe3C是恶化粗晶区韧性的主要原因.超低碳时在粗晶区中形成的马氏体-奥氏体(M-A)组元的含量比低碳时少,M-A组元中残余奥氏体所... 详细信息

X80钢经焊接热模拟后粗晶区组织明显粗化,韧性显著下降.低碳时在粗晶区中的贝氏体铁素体板条间形成的硬而脆的Fe3C是恶化粗晶区韧性的主要原因.超低碳时在粗晶区中形成的马氏体-奥氏体(M-A)组元的含量比低碳时少,M-A组元中残余奥氏体所占的比例大,由于马氏体中偏聚的碳含量低,因而其塑性好,同时因超低碳抑制了Fe3C碳化物的形成而改善了粗晶区的韧性.

关键词：管线钢焊接热模拟粗晶区超低碳贝氏体铁素体马氏体-奥氏体组元

Interannual variability of boreal summer intraseasonal oscillation over the northwestern Pacific influenced by the Pacific Meridional Mode

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 6-11页

作者： Haoyu Zhou Pang-Chi Hsu Lin Chen Yitian qian Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjingChina

During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis *** elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget *** findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern *** increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective *** a process is pivotal in amplifying intraseasonal convection *** observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.

关键词： Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional Mode Moisture budget analysis

The pivotal role of microglia in injury and the prognosis of subarachnoid hemorrhage

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Neural Regeneration Research 2025年第7期20卷 1829-1848页

作者： Wenjing Ning Shi Lv qian Wang Yuzhen Xu Department of Rehabilitation The Second Affiliated Hospital of Shandong First Medical UniversityTaianShandong ProvinceChina Department of Central Laboratory The Affiliated Taian City Central Hospital of Qingdao UniversityTaianShandong ProvinceChina

Subarachnoid hemorrhage leads to a series of pathological changes,including vascular spasm,cellular apoptosis,blood–brain barrier damage,cerebral edema,and white matter ***,which are the key immune cells in the central nervous system,maintain homeostasis in the neural environment,support neurons,mediate apoptosis,participate in immune regulation,and have neuroprotective *** evidence has shown that microglia play a pivotal role in the pathogenesis of subarachnoid hemorrhage and affect the process of injury and the prognosis of subarachnoid ***,microglia play certain neuroprotective roles in the recovery phase of subarachnoid *** approaches aimed at modulating microglia function are believed to attenuate subarachnoid hemorrhage *** provides new targets and ideas for the treatment of subarachnoid ***,an in-depth and comprehensive summary of the role of microglia after subarachnoid hemorrhage is still *** review describes the activation of microglia after subarachnoid hemorrhage and their roles in the pathological processes of vasospasm,neuroinflammation,neuronal apoptosis,blood–brain barrier disruption,cerebral edema,and cerebral white matter *** also discusses the neuroprotective roles of microglia during recovery from subarachnoid hemorrhage and therapeutic advances aimed at modulating microglial function after subarachnoid ***,microglia in subarachnoid hemorrhage are targeted with TLR inhibitors,nuclear factor-κB and STAT3 pathway inhibitors,glycine/tyrosine kinases,NLRP3 signaling pathway inhibitors,Gasdermin D inhibitors,vincristine receptorαreceptor agonists,ferroptosis inhibitors,genetic modification techniques,stem cell therapies,and traditional Chinese ***,most of these are still being evaluated at the laboratory *** clinical studies and data on subarachnoid hemorrhage are required to improve the treatment of subarachnoid hemor

关键词： apoptosis blood–brain barrier brain edema microglia neuroinflammation neuron neuroprotection subarachnoid hemorrhage vasoconstriction white matter injury

Epigenetic regulation of the inflammatory response in stroke

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Neural Regeneration Research 2025年第11期20卷 3045-3062页

作者： Jingyi Liang Fei Yang Zixiao Li qian Li School of Basic Medical Sciences Capital Medical UniversityBeijingChina Department of Neurobiology School of Basic Medical SciencesCapital Medical UniversityBeijingChina Laboratory for Clinical Medicine Beijing Key Laboratory of Neural Regeneration and RepairCapital Medical UniversityBeijingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina National Center for Healthcare Quality Management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina Department of Biochemistry and Molecular Biology School of Basic Medical SciencesCapital Medical UniversityBeijingChina Beijing Key Laboratory of Cancer Invasion and Metastasis Research Capital Medical UniversityBeijingChina

Stroke is classified as ischemic or hemorrhagic,and there are few effective treatments for either *** mechanisms play a critical role in secondary brain injury following a stroke,which manifests as cytokine release,blood–brain barrier disruption,neuronal cell death,and ultimately behavioral *** the inflammatory response has been shown to mitigate this cascade of events in experimental stroke ***,in clinical trials of anti-inflammatory agents,longterm immunosuppression has not demonstrated significant clinical benefits for *** may be attributable to the dichotomous roles of inflammation in both tissue injury and repair,as well as the complex pathophysiologic inflammatory processes in *** acute harmful inflammatory responses or inducing a phenotypic shift from a pro-inflammatory to an anti-inflammatory state at specific time points after a stroke are alternative and promising therapeutic *** agents that can modulate inflammation requires a detailed understanding of the inflammatory processes of ***,epigenetic reprogramming plays a crucial role in modulating post-stroke inflammation and can potentially be exploited for stroke *** this review,we summarize current findings on the epigenetic regulation of the inflammatory response in stroke,focusing on key signaling pathways including nuclear factor-kappa B,Janus kinase/signal transducer and activator of transcription,and mitogen-activated protein kinase as well as inflammasome *** also discuss promising molecular targets for stroke *** evidence to date indicates that therapeutic targeting of the epigenetic regulation of inflammation can shift the balance from inflammation-induced tissue injury to repair following stroke,leading to improved post-stroke outcomes.

关键词： DNA methylation histone modification intracerebral hemorrhage ischemic stroke neuroinflammation neuroprotection non-coding RNA RNA methylation subarachnoid hemorrhage treatment

Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng Xu Sheng Pang Liangwei Cong Guoyu qian Dong Wang Laishi Li Yusheng Wu Zhi Wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis