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rTMS Improves Cognitive Function and Brain Network Connectivity in Patients With Alzheimer’s Disease
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作者 XU Gui-Zhi LIU Lin +4 位作者 GUO Miao-Miao WANG Tian GAO Jiao-Jiao JI Yong WANG Pan 《生物化学与生物物理进展》 北大核心 2025年第8期2131-2145,共15页
Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,n... Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,neural oscillatory dynamics,and brain network reorganization remain unclear.This investigation seeks to systematically evaluate the therapeutic potential of rTMS as a non-invasive neuromodulatory intervention through a multimodal framework integrating clinical assessments,molecular profiling,and neurophysiological monitoring.Methods In this prospective double-blind trial,12 AD patients underwent a 14-day protocol of 20 Hz rTMS,with comprehensive multimodal assessments performed pre-and postintervention.Cognitive functioning was quantified using the mini-mental state examination(MMSE)and Montreal cognitive assessment(MOCA),while daily living capacities and neuropsychiatric profiles were respectively evaluated through the activities of daily living(ADL)scale and combined neuropsychiatric inventory(NPI)-Hamilton depression rating scale(HAMD).Peripheral blood biomarkers,specifically Aβ1-40 and phosphorylated tau(p-tau181),were analyzed to investigate the effects of rTMS on molecular metabolism.Spectral power analysis was employed to investigate rTMS-induced modulations of neural rhythms in AD patients,while brain network analyses incorporating topological properties were conducted to examine stimulus-driven network reorganization.Furthermore,systematic assessment of correlations between cognitive scale scores,blood biomarkers,and network characteristics was performed to elucidate cross-modal therapeutic associations.Results Clinically,MMSE and MOCA scores improved significantly(P<0.05).Biomarker showed that Aβ1-40 level increased(P<0.05),contrasting with p-tau181 reduction.Moreover,the levels of Aβ1-40 were positively correlated with MMSE and MOCA scores.Post-intervention analyses revealed significant modulations in oscillatory power,characterized by pronounced reductions in delta(P<0.05)and theta bands(P<0.05),while concurrent enhancements were observed in alpha,beta,and gamma band activities(all P<0.05).Network analysis revealed frequency-specific reorganization:clustering coefficients were significantly decreased in delta,theta,and alpha bands(P<0.05),while global efficiency improvement was exclusively detected in the delta band(P<0.05).The alpha band demonstrated concurrent increases in average nodal degree(P<0.05)and characteristic path length reduction(P<0.05).Further research findings indicate that the changes in the clinical scale HAMD scores before and after rTMS stimulation are negatively correlated with the changes in the blood biomarkers Aβ1-40 and p-tau181.Additionally,the changes in the clinical scales MMSE and MoCA scores were negatively correlated with the changes in the node degree of the alpha frequency band and negatively correlated with the clustering coefficient of the delta frequency band.However,the changes in MMSE scores are positively correlated with the changes in global efficiency of both the delta and alpha frequency bands.Conclusion 20 Hz rTMS targeting dorsolateral prefrontal cortex(DLPFC)significantly improves cognitive function and enhances the metabolic clearance ofβ-amyloid and tau proteins in AD patients.This neurotherapeutic effect is mechanistically associated with rTMS-mediated frequency-selective neuromodulation,which enhances the connectivity of oscillatory networks through improved neuronal synchronization and optimized topological organization of functional brain networks.These findings not only support the efficacy of rTMS as an adjunctive therapy for AD but also underscore the importance of employing multiple assessment methods—including clinical scales,blood biomarkers,and EEG——in understanding and monitoring the progression of AD.This research provides a significant theoretical foundation and empirical evidence for further exploration of rTMS applications in AD treatment. 展开更多
关键词 transcranial magnetic stimulation Alzheimer’s disease power spectral density ELEcTROENcEPHALOGRAM brain functional network
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The Fundamental Construction and Social Development of China’s Network Society
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作者 Xie Jungui 《Contemporary Social Sciences》 2025年第5期122-139,共18页
The idea of a network society was introduced by Western sociologists at the end of the 20th century after in-depth research was conducted from perspectives such as informationalism.Influenced by these developments,the... The idea of a network society was introduced by Western sociologists at the end of the 20th century after in-depth research was conducted from perspectives such as informationalism.Influenced by these developments,the concept of constructing a network society also emerged in China.Over the past 30 years,China has made significant progress and achievements in constructing a network society,both in terms of its fundamental construction and social development.It is important that these advancements be summarized and reviewed.China’s network society construction can be divided into two relatively independent yet interconnected components,based on their focal points:its foundational infrastructure and its social development.These two components of China’s network society are managed by different departments.China has integrated the fundamental construction of its network society with the social development of its network society,thereby achieving unified planning,collaborative advancement,and coordinated development.This approach aims to harmonize two aspects:building China’s cyberspace strength and contributing to Chinese informatization,thereby advancing Chinese modernization. 展开更多
关键词 network society information society INFRAsTRUcTURE social development network society construction building china’s cyberspace strength network society planning
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Mechanism of Limonoid Compounds Against Alzheimer s Disease Based on Network Pharmacology and Molecular Docking
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作者 Mao SUN Weiqing ZHANG +2 位作者 Weixian YANG Meihui DUAN Xianji LIU 《Agricultural Biotechnology》 2025年第4期58-65,72,共9页
[Objectives]This study was conducted to explore the action mechanism of limonoids against Alzheimer s disease(AD)based on network pharmacology and molecular docking techniques.[Methods]Limonoid compounds were obtained... [Objectives]This study was conducted to explore the action mechanism of limonoids against Alzheimer s disease(AD)based on network pharmacology and molecular docking techniques.[Methods]Limonoid compounds were obtained through literature research(January 1942 to January 2021).Active components and potential targets of limonoids were retrieved from PubChem,TCMSP,and Swiss Target Prediction databases.AD-related targets were obtained from the GeneCards database,and intersecting targets were identified using Venny 2.1.0 to obtain the action targets of limonoids against AD.The protein-protein interaction(PPI)network was constructed using the String platform,and key targets were screened and visualized via network topology analysis with Cytoscape software.GO and KEGG pathway enrichment analyses were performed using the Metascape database,and a"drug-component-target-pathway-disease"network diagram was constructed using Cytoscape.AutoDock was empolyed for molecular docking to predict the binding properties of limonoid active components and their targets.[Results]A total of 60 limonoid compounds were obtained from literature research.Network pharmacology analysis showed 58 effective active components and 134 common targets between limonoids and AD.Key targets included AKT1(serine/threonine-protein kinase 1),TNF(tumor necrosis factor),STAT3(signal transducer and activator of transcription 3),BCL2(B-cell lymphoma 2),and EGFR(epidermal growth factor receptor).KEGG enrichment analysis revealed key signaling pathways such as pathways in cancer,Kaposi sarcoma-associated herpesvirus infection,PI3K-Akt signaling pathway,lipid and atherosclerosis,proteoglycans in cancer,MAPK signaling pathway,and Ras signaling pathway.Molecular docking results indicated that aphanamixoid A,obacunol,cipadesin C,harpertrioate A,xylogranatin A,11-oxocneorin G,evodulone,methyl angolensate,harrpemoid B and khivorin may be key components of limonoids against AD.[Conclusions]Limonoids exert anti-Alzheimer s effects through a multi-molecule,multi-target and multi-pathway mechanism. 展开更多
关键词 LIMONOIDs Alzheimer s disease network pharmacology Molecular docking
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Exploring the mechanism of Crataegus pinnatifida fruit flavonoids to improve Alzheimer’s disease based on network pharmacology and molecular docking
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作者 Dehong Zhang Xuqian Niu +8 位作者 Rongzheng Deng Anna Gan Fei Lin Jinyu Wang Bo Wu Tingxu Yan Ying Jia Wei Zheng Xu Zhao 《Journal of Polyphenols》 2025年第2期59-69,共11页
This study aims to explore the mechanism by which flavonoids in Crataegus pinnatifida fruit improve Alzheimer’s disease(AD)through network pharmacology and molecular docking technology.The flavonoid components presen... This study aims to explore the mechanism by which flavonoids in Crataegus pinnatifida fruit improve Alzheimer’s disease(AD)through network pharmacology and molecular docking technology.The flavonoid components present in Crataegus pinnatifida fruit were gathered from the HERB,HIT,and ETCM databases,and were further supplemented by relevant published literature.The PubChem and SwissTargetPrediction databases were utilized to predict potential targets,and a“Crataegus pinnatifida fruit-active ingredient-target”network was constructed using Cytoscape 3.9.0 software.The GeneCards database was utilized to identify targets associated with AD,which were subsequently intersected with the active targets of Crataegus pinnatifi da fruit.A protein-protein interaction(PPI)network was constructed using the STRING platform.KEGG enrichment analysis of the core targets was conducted on an online bioinformatics mapping platform,while molecular docking of the primary active components and core targets was executed using AutoDock software.Eight flavonoids and 160 potential targets were identifi ed from Crataegus pinnatifi da fruit,of which 147 targets were linked to AD.The results of the“Crataegus pinnatifi da fruit-active ingredient-target”network indicated that quercetin was the principal flavonoid active ingredient.PPI analysis revealed that SRC and EGFR were the key targets,and KEGG analysis identifi ed the main enrichment pathways as Pathways in cancer,PI3K/Akt signaling pathway,and Proteoglycans in cancer.Molecular docking confi rmed the strong binding affi nity between the core targets and the primary active ingredient.The interaction of quercetin with the key targets SRC and EGFR may represent a signifi cant mechanism by which flavonoids from Crataegus pinnatifi da fruit contribute to the improvement of AD. 展开更多
关键词 crataegus pinnatifi da fruit FLAVONOIDs Alzheimer’s disease network pharmacology molecular docking
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Cytotoxic anthrone–cyclopentenone heterodimers from the fungus Penicillium sp.guided by molecular networking
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作者 Ruiyun Huo Jiayu Dong +2 位作者 Gaoran Liu Ying Shi Ling Liu 《Chinese Journal of Natural Medicines》 2025年第10期1259-1267,共9页
(±)-Penicithrones A–D(1a/1b–4a/4b),four novel pairs of anthrone–cyclopentenone heterodimers characterized by a distinctive bridged 6/6/6−5 tetracyclic core skeleton,together with three previously identified co... (±)-Penicithrones A–D(1a/1b–4a/4b),four novel pairs of anthrone–cyclopentenone heterodimers characterized by a distinctive bridged 6/6/6−5 tetracyclic core skeleton,together with three previously identified compounds(5–7),were isolated from the crude extract of the mangrove-derived fungus Penicillium sp.,guided by heteronuclear single quantum correlation(HSQC)-based small molecule accurate recognition technology(SMART 2.0)and liquid chromatography-tandem mass spectrometry(LC-MS/MS)-based molecular networking.The structural elucidation of new compounds was accomplished through comprehensive spectroscopic analysis,and their absolute configurations were determined using DP4+^(13)C nuclear magnetic resonance(NMR)calculations and electronic circular dichroism(ECD)calculations.Compounds 1a/1b–4a/4b demonstrated moderate cytotoxicity against three human cancer cell lines HeLa,HCT116 and MCF-7 with half maximal inhibitory concentration(IC50)values ranging from 15.95±1.64 to 28.56±2.59μmol·L–1. 展开更多
关键词 Mangrove-derived fungi Molecular networking HsQc-based sMART structure elucidation DP4%PLUs%13c NMR calculation cytotoxic activity
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Actuator Fault Diagnosis of 3-PR(P)S Parallel Robot Based on Dung Beetle Optimization-Back Propagation Neural Network
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作者 Junjie Huang Chenhao Huangfu +3 位作者 Qinlei Zhang Shikai Li Yonggang Yan Jiangkun Cai 《Journal of Dynamics, Monitoring and Diagnostics》 2025年第2期91-100,共10页
Any malfunctions of the actuators of the robots have the potential to destroy the robot’s normal motion,and most of the current actuator fault diagnosis methods are difficult to meet the requirements of simplifying t... Any malfunctions of the actuators of the robots have the potential to destroy the robot’s normal motion,and most of the current actuator fault diagnosis methods are difficult to meet the requirements of simplifying the actuator modeling and solving the difficulty of fault data collection.To solve the problem of real-time diagnosis of actuator faults in the 3-PR(P)S parallel robot,the model of 3-PR(P)S parallel robot and data-driven-based method for the fault diagnosis are presented.Firstly,only the input-output relationship of the actuator is considered for modeling actuator faults,reducing the complexity of fault modeling and reducing the time consumption of parameter identification,thereby meeting the requirements of real-time diagnosis.A Simulink model of the electromechanical actuator(EMA)was constructed to analyze actuator faults.Then the short-term analysis method was employed for collecting the sample data of the slider position on the test platform of the EMA system and feature extraction.Training samples for neural networks are obtained.Furthermore,we optimized the Back Propagation(BP)neural network using the Dung Beetle Optimization Algorithm(DBO),which effectively resolved the weights and thresholds of the BP neural network.Compared to BP and Particle Swarm Optimization(PSO)-BP,the DBO-BP has better convergence,convergence rate,and the best-classifying quality.So,the classification for the different actuator faults is obviously improved.Finally,a fault diagnosis system was designed for the actuator of the 3-PR(P)S parallel robot,and the experimental results demonstrate that this system can detect actuator faults within 0.1 seconds.This work also provides the technical support for the fault-tolerant control of the 3-PR(P)S Parallel robot. 展开更多
关键词 AcTUATOR Back Propagation neural network Dung Beetle Algorithm fault diagnosis 3-PR(P)s parallel robot
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Call for Papers─Feature Topic Vol.23,No.2,2026 Beyond Terrestrial Infrastructure: Meteor Burst Communications for Next-Generation Emergency Communication Networks
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《China Communications》 2025年第8期I0002-I0002,共1页
Meteor Burst Communication(MBC),a niche yet revolutionary wireless communication paradigm,exploits the transient ionized trails generated by meteors ablating in Earth’s atmosphere to enable sporadic yet resilient lon... Meteor Burst Communication(MBC),a niche yet revolutionary wireless communication paradigm,exploits the transient ionized trails generated by meteors ablating in Earth’s atmosphere to enable sporadic yet resilient long-distance radio links.Known for its exceptional resilience,robustness,and sustained connectivity,MBC holds significant promise for applications in emergency communications,remote area connectivity,military/defense systems,and environmental monitoring.However,the scientific exploration and application of MBC have long been highly challenging.In particular,under the combined influence of multiple physical field factors,the channel experiences superimposed multiple random fading effects,exhibiting bursty,highly time-varying,and strongly random characteristics.This persistent technical challenge has resulted in the absence of a practical statistical channel model for MBC to date. 展开更多
关键词 wireless communication paradigmexploits earth s atmosphere Resilient Long Distance Radio Links Emergency communication networks Meteor Burst communications emergency communicationsremote area connectivitymilitary defense transient ionized trails meteor burst communication mbc
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New criteria on the existence and global exponential stability of periodic solutions for quaternion-valued cellular neural networks
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作者 LI Ai-ling ZHOU Zheng ZHANG Zheng-qiu 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期523-542,共20页
In this paper,a class of quaternion-valued cellular neural networks(QVCNNS)with time-varying delays are considered.Combining graph theory with the continuation theorem of Mawhin’s coincidence degree theory as well as... In this paper,a class of quaternion-valued cellular neural networks(QVCNNS)with time-varying delays are considered.Combining graph theory with the continuation theorem of Mawhin’s coincidence degree theory as well as Lyapunov functional method,we establish new criteria on the existence and exponential stability of periodic solutions for QVCNNS by removing the assumptions for the boundedness on the activation functions and the assumptions that the values of the activation functions are zero at origin.Hence,our results are less conservative and new. 展开更多
关键词 the existence of periodic solutions exponential stability quaternion-valued cellular neural networks combining graph theory with Mawhin’s continuation theorem of coincidence degree theory Lyapunov function method inequality techniques
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不同NIHSS评分缺血性脑卒中患者血清CatS VILIP-1 CysC水平变化与疾病转归的相关性 被引量:1
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作者 刘义锋 余洋 +3 位作者 刘少哲 张东焕 孙孟 温昌明 《中国实用神经疾病杂志》 2025年第2期223-227,共5页
目的探讨不同NIHSS评分缺血性脑卒中(CIS)患者血清组织蛋白酶S(CatS)、视锥蛋白样蛋白-1(VILIP-1)、胱抑素C(CysC)水平变化及其与疾病转归的相关性。方法选取2021-01—2023-01南阳市中心医院收治的143例CIS患者为研究对象,根据入院时NI... 目的探讨不同NIHSS评分缺血性脑卒中(CIS)患者血清组织蛋白酶S(CatS)、视锥蛋白样蛋白-1(VILIP-1)、胱抑素C(CysC)水平变化及其与疾病转归的相关性。方法选取2021-01—2023-01南阳市中心医院收治的143例CIS患者为研究对象,根据入院时NIHSS评分分为低分组(43例,NIHSS评分<4分)、中分组(68例,NIHSS评分4~15分)和高分组(32例,NIHSS评分>15分)。比较3组入院时血清CatS、VILIP-1、CysC水平,分析其与NIHSS评分的相关性,比较不同疾病转归患者血清各指标水平,偏回归分析CIS患者转归不良的影响因素,ROC分析各指标联合检测对CIS患者转归不良的预测价值。结果入院时低分组血清CatS、VILIP-1、CysC水平分别为(53.18±6.74)ng/L、(4.57±1.38)μg/L、(1.08±0.32)mg/L,低于中分组[(76.53±9.25)ng/L、(9.63±2.44)μg/L、(1.74±0.39)mg/L]和高分组[(98.44±8.61)ng/L、(16.72±3.55)μg/L、(2.53±0.47)mg/L],各指标水平与NIHSS评分均呈正相关(P<0.05)。治疗1周、2周后转归不良患者血清CatS、VILIP-1、CysC水平[治疗1周后:(73.35±8.44)ng/L、(9.25±2.44)μg/L、(1.73±0.33)mg/L;治疗2周后:(70.96±9.02)ng/L、(8.74±2.13)μg/L、(1.71±0.30)mg/L]高于转归良好患者[治疗1周后:(55.87±6.29)ng/L、(6.15±2.03)μg/L、(1.01±0.31)mg/L;治疗2周后:(31.95±6.24)ng/L、(2.86±0.74)μg/L、(0.64±0.19)mg/L](P<0.05)。治疗1周、治疗2周后血清CatS、VILIP-1、CysC水平为CIS患者转归不良的危险因素,联合检测预测CIS患者转归不良的AUC分别为0.784、0.838。结论血清CatS、VILIP-1、CysC水平与CIS患者神经功能损伤程度及疾病转归密切相关,联合检测可作为临床判断神经功能损伤程度、预测转归情况的有效依据。 展开更多
关键词 缺血性脑卒中 疾病转归 组织蛋白酶s 视锥蛋白样蛋白-1 胱抑素c 血清
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高碳含硫非调质连杆用钢C70S6精炼渣系热力学计算
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作者 姜晓东 杨乃辉 +5 位作者 张伟 李明林 武永孝 高旭东 刘治权 铁占鹏 《钢铁》 北大核心 2025年第7期251-261,共11页
非调质易切削钢广泛用于汽车等交通运输行业,C70S6钢是发动机胀断连杆用最具代表性的非调质易切削钢,开发并优化C70S6钢精炼造渣工艺来保障其产品成分与组织性能稳定可控,具有重要的工业价值和学术意义。钢包精炼渣系是钢包冶金的重要内... 非调质易切削钢广泛用于汽车等交通运输行业,C70S6钢是发动机胀断连杆用最具代表性的非调质易切削钢,开发并优化C70S6钢精炼造渣工艺来保障其产品成分与组织性能稳定可控,具有重要的工业价值和学术意义。钢包精炼渣系是钢包冶金的重要内容,其具有脱氧、脱硫、吸收夹杂物和稳定钢水中氮、硫含量的作用。针对C70S6钢“高碳、高硫、高氮、低铝、低硅”“三高二低”的成分控制目标与特点,基于FactSage热力学软件、KTH硫容量模型(Kth-order sufur capacity model)研究了不同精炼渣成分的特点,提出了满足硫含量控制要求的“变渣”操作工艺,即在LF(ladle furnace)精炼前期造高碱度渣强化扩散脱氧,以弥补其低铝、低硅要求造成的出钢沉淀脱氧能力不足,并为后期增氮创造了良好条件;而在精炼后期VD(vacuum degassing)阶段造低碱度渣增硫,以满足其因切削性要求保硫的目的。研究表明,钙铝比和碱度是精炼渣熔化性能的主要影响因素。C70S6钢渣系在高效脱氧脱硫阶段的目标是控制渣系碱度为3~6、MgO质量分数为4%~6%、钙铝比为1.5~2.2,渣系熔点低、流动性好,且对铝脱氧产生的Al_(2)O_(3)类夹杂物有较好的吸收和改性效果;而在保硫阶段的目标是渣系控制渣系碱度为2.0~3.5、MgO质量分数为4%~6%、钙铝比为2.3~3.3,具有较好的对钢水增硫保硫性能。此研究结果对高碳含硫非调质钢在不同阶段冶炼过程中调整渣系组元以达到钢水化学成分和洁净度的控制具有指导意义。 展开更多
关键词 c70s6钢 胀断连杆 精炼 渣系 高碱度脱氧 低碱度保硫 易切削钢 钢包
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基于PC SDK的智能装配工作站远程监控系统研究与设计
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作者 梁盈富 赵豆 祝战科 《机械制造与自动化》 2025年第1期131-134,共4页
以智能装配工作站为研究对象,运用机器人控制器的PC SDK接口对工作站系统进行二次开发,研究了智能装配工作站的网络架构,并在C/S架构下设计工业机器人智能装配工作站远程监控方案,开发了智能装配工作站远程监控系统。实验结果表明:该系... 以智能装配工作站为研究对象,运用机器人控制器的PC SDK接口对工作站系统进行二次开发,研究了智能装配工作站的网络架构,并在C/S架构下设计工业机器人智能装配工作站远程监控方案,开发了智能装配工作站远程监控系统。实验结果表明:该系统能够有效完成对工作站运行状态的远程监控,实现对机器人远程操作及运行状态的获取。 展开更多
关键词 Pc sDK c/s架构 远程监控 智能装配工作站
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温度对Hastelloy C-276镍基合金离子碳氮共渗组织与性能影响
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作者 曹驰 张春华 +2 位作者 陈志林 张翔 张果林 《材料科学与工艺》 北大核心 2025年第2期27-34,共8页
探究温度对镍基合金Hastelloy C-276渗层显微组织、力学性能、摩擦磨损性能以及耐蚀性能的影响规律,以期获得硬度、耐磨性和耐蚀性优良的表面改性层。使用等离子碳氮共渗技术在不同温度(395、425、455、485℃)下制备表面改性层,镍基合金... 探究温度对镍基合金Hastelloy C-276渗层显微组织、力学性能、摩擦磨损性能以及耐蚀性能的影响规律,以期获得硬度、耐磨性和耐蚀性优良的表面改性层。使用等离子碳氮共渗技术在不同温度(395、425、455、485℃)下制备表面改性层,镍基合金C-276经离子碳氮共渗后,渗层厚度从6.5到20.0μm不等,表面硬度较原始合金均有不同程度提高。当处理温度≤395℃时生成的S相层较薄;随着处理温度升高,生成较厚的S相层和CrN硬质相,获得优良的耐磨性;进一步提升处理温度至485℃时,基体表面出现贫Cr,致使合金耐蚀性降低;当处理温度<450℃时样品表现出比基体更好的耐蚀性能。镍基合金Hastelloy C-276在425、455℃温度下进行碳氮共渗,可获得硬度、耐磨性和耐蚀性相对优良的表面改性层。 展开更多
关键词 碳氮共渗 Hastelloy c-276镍基合金 s 温度 耐磨性
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Ni-W镀层在高含CO_(2)/H_(2)S环境中的腐蚀行为
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作者 吕祥鸿 曹悦 +4 位作者 汪传磊 薛艳 李杰 刘艳明 代盼 《中国有色金属学报》 北大核心 2025年第5期1660-1673,共14页
采用失重法、表面特性表征以及高温高压电化学测试技术,系统研究Ni-W镀层在模拟地层水环境(高CO_(2)/H_(2)S含量,温度140~180℃)下的高温高压腐蚀行为,同时采用C110钢进行对比实验。结果表明:相较于C110钢,Ni-W镀层展现出更低的均匀腐... 采用失重法、表面特性表征以及高温高压电化学测试技术,系统研究Ni-W镀层在模拟地层水环境(高CO_(2)/H_(2)S含量,温度140~180℃)下的高温高压腐蚀行为,同时采用C110钢进行对比实验。结果表明:相较于C110钢,Ni-W镀层展现出更低的均匀腐蚀速率、点蚀速率以及腐蚀电流密度。Ni-W镀层在140~160℃温度范围内呈现中度腐蚀,在高温180℃时转变为严重腐蚀;相比之下,C110钢在整个测试温度范围内均表现为严重腐蚀,且腐蚀速率远大于Ni-W镀层;Ni-W镀层表面形成的腐蚀产物膜主要由NiS、Ni_(3)S_(2)及微量Ni(OH)_(2)构成,该膜层结构致密,化学稳定性高,与基体结合牢固,且腐蚀产物膜电阻大于C110腐蚀产物FexSy,可有效抑制Ni-W镀层在长期浸泡过程中的腐蚀进程。 展开更多
关键词 Ni-W镀层 高温地层水 cO_(2)/H_(2)s腐蚀 c110钢
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孕晚期血浆中AT-Ⅲ、PC和PS水平与胎儿生长受限的相关性分析
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作者 曾甲子 张迪 +4 位作者 翟燕红 朱宏远 曹妍 卢一凡 曹正 《标记免疫分析与临床》 2025年第4期687-690,753,共5页
目的探究孕晚期血浆中AT-Ⅲ、PC和PS与胎儿生长受限(FGR)的相关性。方法选择2020年1月至2021年12月间在北京妇产医院建档的198例诊断为胎儿生长受限的孕晚期孕妇为研究对象,另选222例健康单胎孕晚期孕妇为对照组。检测两组孕晚期孕妇血... 目的探究孕晚期血浆中AT-Ⅲ、PC和PS与胎儿生长受限(FGR)的相关性。方法选择2020年1月至2021年12月间在北京妇产医院建档的198例诊断为胎儿生长受限的孕晚期孕妇为研究对象,另选222例健康单胎孕晚期孕妇为对照组。检测两组孕晚期孕妇血浆中PC、PS、AT-Ⅲ的水平;采用受试者工作特征曲线分析上述指标对胎儿生长受限的预测价值;采用多因素Logistic回归分析这3种指标中FGR的影响因素。结果FGR组的孕妇血清中PC、PS、AT-Ⅲ的水平均低于对照组,且差异均有统计学意义(P<0.05);ROC曲线分析的结果显示,血浆PS、PC、和AT-Ⅲ水平单项预测FGR的AUC分别为0.71(95%CI:0.67~0.75)、0.56(95%CI:0.51~0.61)、0.61(95%CI:0.56~0.66),3项指标联合预测胎儿生长受限的AUC为0.72(95%CI:0.67~0.77),均高于PS、PC、AT-Ⅲ单独诊断的AUC;多因素Logistic回归分析的结果显示,PS和AT-Ⅲ低水平是孕妇发生FGR的危险因素(P<0.05)。结论FGR孕妇血清PC、PS、AT-Ⅲ水平显著降低,3个指标的联合检测对于预测FGR具有一定的诊断意义。 展开更多
关键词 胎儿生长受限 Ps Pc AT-Ⅲ
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C5aR1、BDKRB1、G0S2、HIF-1α在胃癌前病变进展中的预测价值
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作者 李扬 年媛媛 孟宪梅 《包头医学院学报》 2025年第5期72-76,83,共6页
目的:探讨C5a受体(C5aR1)、缓激肽受体B1(bradykinin receptor B1,BDKRB1)、缺氧诱导因子-1α(hypoxia inducible factor-1α,HIF-1α)、G0/G1开关2(G0/G1 switch 2,G0S2)基因在肠型胃癌Correa发展模式中的表达特点,筛选胃癌前病变进展... 目的:探讨C5a受体(C5aR1)、缓激肽受体B1(bradykinin receptor B1,BDKRB1)、缺氧诱导因子-1α(hypoxia inducible factor-1α,HIF-1α)、G0/G1开关2(G0/G1 switch 2,G0S2)基因在肠型胃癌Correa发展模式中的表达特点,筛选胃癌前病变进展的预测因子。方法:选取慢性非萎缩性胃炎(chronic non-atrophic gastritis,CNAG)、慢性萎缩性胃炎(chronic atrophic gastritis,CAG)、低级别上皮内瘤变(low-grade intraepithelial neoplasia,LGIN)、高级别上皮内瘤变(high-grade intraepithelial neoplasia,HGIN)、侵及黏膜层及黏膜下层的早期胃癌(early gastric cancer,EGC)组织蜡块,应用免疫组化法检测各组织中C5aR1、BDKRB1、G0S2及HIF-1α的蛋白表达水平。结果:C5aR1主要表达于细胞膜与细胞质中,BDKRB1主要表达于细胞膜中,G0S2和HIF-1α主要表达于细胞质与细胞核中。HGIN、EGC组织中C5aR1、BDKRB1、G0S2的表达水平显著高于CAG和CNAG(P<0.001)。HGIN、EGC组织中HIF-1α表达水平显著高于CNAG(P<0.001),但与CAG相比差异无统计学意义。4个因子在LGIN与其他组织中的表达结果相比差异均无统计学意义,在CNAG和CAG组织中的表达结果相比差异无统计学意义。结论:C5aR1、BDKRB1、G0S2和HIF-1α表达量随着肠型胃癌Correa发展阶段呈增加趋势,可能具有预测胃癌前病变进展的价值。 展开更多
关键词 c5aR1 BDKRB1 G0s2 HIF-1Α 胃癌前病变
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中国主要类型铅锌矿床S、Pb、C-H-O同位素特征及其成因意义 被引量:1
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作者 刘榆 江彪 +4 位作者 王登红 王岩 宋学信 张长青 黄凡 《地球学报》 北大核心 2025年第1期93-115,共23页
铅、锌是重要的矿产资源,在工业生产中发挥着至关重要的作用。S、Pb、C-H-O同位素地球化学可以用来解释成矿物质来源、成矿流体来源及矿床成因等地质问题。对铅锌矿床的稳定同位素研究自20世纪80年代至今已取得丰硕成果,为从单矿种角度... 铅、锌是重要的矿产资源,在工业生产中发挥着至关重要的作用。S、Pb、C-H-O同位素地球化学可以用来解释成矿物质来源、成矿流体来源及矿床成因等地质问题。对铅锌矿床的稳定同位素研究自20世纪80年代至今已取得丰硕成果,为从单矿种角度进行全国性的总结奠定了良好基础。本文基于全国重要铅锌矿床的相关硫、铅、氢、氧、碳同位素近万条数据进行分析,结果显示,中国铅锌矿床的S、Pb同位素特征揭示其成矿物质来源复杂,主要为深源岩浆和赋矿地层(海水沉积物),H-O、C-O同位素特征表明中国铅锌矿床的成矿流体中的水主要为岩浆水和大气降水,而成矿流体中的碳主要来源于岩浆和海相碳酸盐岩。S同位素的空间分布特征显示,从我国西部到东部地区,北部到南部地区,铅锌矿床的32S趋于富集,表明我国东部和南部铅锌矿床有更多壳源物质参与成矿。C-H-O同位素特征显示相较于西北部地区,我国东南部地区的铅锌矿床有更多大气降水或盆地卤水参与成矿。 展开更多
关键词 铅锌矿 s同位素 PB同位素 c-H-O同位素 地球化学
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^(12)C+^(12)C熔合反应天体物理S^(*)因子的研究现状
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作者 南威克 王友宝 +3 位作者 谌阳平 李云居 郭冰 柳卫平 《原子核物理评论》 北大核心 2025年第2期199-204,共6页
近二十年来,中子星表面由^(12)C+^(12)C熔合反应触发的超级X-射线暴天文观测结果,无法用现有的基于外推得到的^(12)C+^(12)C熔合反应率解释,因此对极低库仑势垒能量下^(12)C+^(12)C熔合反应截面进行测量成为了核天体物理研究的一个热点... 近二十年来,中子星表面由^(12)C+^(12)C熔合反应触发的超级X-射线暴天文观测结果,无法用现有的基于外推得到的^(12)C+^(12)C熔合反应率解释,因此对极低库仑势垒能量下^(12)C+^(12)C熔合反应截面进行测量成为了核天体物理研究的一个热点。然而,超级暴典型的^(12)C+^(12)C熔合反应伽莫夫窗口为1.5±0.3 MeV,远低于熔合反应库仑势垒。这使得用直接测量方法对该能区内极低的熔合反应截面进行研究成为一个巨大的挑战。特洛伊木马方法实验(THM)是目前唯一能给出伽莫夫窗口内各出射道激发函数的带电粒子测量实验,然而其结果目前仍存在很大争议。本工作回顾了^(12)C+^(12)C熔合反应直接测量实验的研究现状,并对THM的数据分析结果提出了新的解读。结合全同玻色子体系理论对THM提取的复合核24Mg激发态进行讨论,首次给出^(12)C+^(12)C熔合反应入射道无量纲约化宽度推荐平均值θ2=0.031,与反对称分子动力学模型(AMD)在相应能区的理论预言相一致。 展开更多
关键词 核天体物理 ^(12)c%PLUs%^(12)c熔合反应 特洛伊木马方法 天体物理s^(*)因子
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镍催化交叉偶联构建C(sp^(3))—S/Se键合成半胱氨酸衍生物
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作者 代刚良 周丽娟 +3 位作者 张鹏 李鑫雨 肖美球 唐石 《应用化学》 北大核心 2025年第8期1115-1124,共10页
发展了一种镍催化β-溴氨基酸酯与硫醚的交叉偶联反应,高效合成一系列新颖的半胱氨酸衍生物。反应使用简单易得、结构稳定的β-溴氨基酸酯和二苯基二硫醚作为偶联前体,在四(三苯基膦)镍(0)/1,10-啡罗啉催化体系下,以中等至良好(58%~82%... 发展了一种镍催化β-溴氨基酸酯与硫醚的交叉偶联反应,高效合成一系列新颖的半胱氨酸衍生物。反应使用简单易得、结构稳定的β-溴氨基酸酯和二苯基二硫醚作为偶联前体,在四(三苯基膦)镍(0)/1,10-啡罗啉催化体系下,以中等至良好(58%~82%)的收率得到半胱氨酸衍生物。此外,该反应采用“一锅法”通过一步合成的策略成功构建了C(sp^(3))-S键,并进一步拓展至C(sp^(3))-O/Se键的高效形成,实现了硒代半胱氨酸和丝氨酸衍生物的模块化合成。反应条件温和、操作简单和底物兼容性好,为具有潜在药用价值的半胱氨酸、丝氨酸衍生物的合成提供新的方向。 展开更多
关键词 镍催化 交叉偶联 c(sp^(3))—s c(sp^(3))—O/se键 半胱氨酸衍生物 丝氨酸衍生物
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妊娠期血栓性疾病患者血浆PC、PS、AT-Ⅲ活性变化及其临床意义 被引量:2
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作者 李春美 余莹莹 +3 位作者 陆光辉 王鑫 李小兰 安冬梅 《中国医药导刊》 2025年第2期177-181,共5页
目的:探讨妊娠期血栓性疾病患者血浆蛋白C(PC)、蛋白S(PS)、抗凝血酶III(AT-III)活性变化及其临床意义。方法:选取2018年8月至2020年8月我院收治的61例妊娠期血栓性疾病孕妇为栓塞组,另选取同期于我院进行孕检的健康孕妇73例为健康组,... 目的:探讨妊娠期血栓性疾病患者血浆蛋白C(PC)、蛋白S(PS)、抗凝血酶III(AT-III)活性变化及其临床意义。方法:选取2018年8月至2020年8月我院收治的61例妊娠期血栓性疾病孕妇为栓塞组,另选取同期于我院进行孕检的健康孕妇73例为健康组,比较分析栓塞组和健康组孕妇的基本资料。发色底物法检测血浆PC、AT-III活性,凝固法检测血浆PS活性,比较两组孕妇血浆PC、PS和AT-III活性变化。使用多因素Logistic回归分析妊娠期血栓性疾病的危险因素,受试者工作特征曲线(ROC)分析血浆PC、PS和AT-III活性及其联合检测时对妊娠期血栓性疾病的诊断效能。将栓塞组孕妇根据其妊娠结局分为终止妊娠组(15例)和继续妊娠组(46例),比较不同妊娠结局孕妇血浆PC、PS和AT-III活性变化。结果:栓塞组孕妇年龄≥35岁、孕前肥胖(BMI≥30 kg·m^(-2))、血栓性疾病家族史、吸烟、产次、合并高血压构成比例均高于健康组(P<0.05),血浆PC、PS、AT-III活性均低于健康组(P<0.05)。危险因素分析显示年龄≥35岁、孕前肥胖、血栓性疾病家族史、血浆PC(<75.52%)、PS(<53.61%)、AT-III(<84.66%)活性是妊娠期血栓性疾病的危险因素。ROC分析显示,血浆PC、PS、AT-III及其联合检测时的曲线下面积(AUC)分别为0.802、0.773、0.832、0.941,灵敏度分别为59.0%、72.1%、67.2%、83.6%,特异度分别为89.0%、74.0%、86.3%、90.4%,联合检测时的AUC高于血浆PC、PS、AT-III单独检测(P<0.05)。终止妊娠组孕妇的血浆PC、PS、AT-III活性均低于继续妊娠组(P<0.05)。结论:妊娠期血栓性疾病患者血浆PC、PS、AT-III活性呈降低趋势,其联合检测可以提高妊娠期血栓性疾病诊断效能。 展开更多
关键词 妊娠期血栓性疾病 蛋白c 蛋白s 抗凝血酶III 临床意义
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不同养护条件下C-S-H/PCE晶种对C_(3)S早期水化产物微观结构的影响
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作者 王彦荣 伍勇华 +2 位作者 易昂 王欣 陈舒文 《硅酸盐通报》 北大核心 2025年第10期3517-3524,共8页
硅酸三钙(C_(3)S)是硅酸盐水泥的主要矿物相,其水化产物决定着硅酸盐水泥基材料的性能。添加水化硅酸钙(C-S-H)晶种可以调控C_(3)S水化产物的微观结构。本文采用共沉淀法,以聚羧酸(PCE)为分散剂合成不同钙硅摩尔比的水化硅酸钙/PCE(C-S-... 硅酸三钙(C_(3)S)是硅酸盐水泥的主要矿物相,其水化产物决定着硅酸盐水泥基材料的性能。添加水化硅酸钙(C-S-H)晶种可以调控C_(3)S水化产物的微观结构。本文采用共沉淀法,以聚羧酸(PCE)为分散剂合成不同钙硅摩尔比的水化硅酸钙/PCE(C-S-H/PCE)晶种,通过XRD、热重分析及SEM表征,研究了C-S-H/PCE晶种对C_(3)S单矿物早期水化产物微观结构的影响机制。结果表明:20℃标养24 h时掺入C-S-H/PCE晶种可以促进C_(3)S水化,生成更多的氢氧化钙(CH),晶种钙硅摩尔比为1.2时诱导生成的C-S-H凝胶数量最多,结构最为致密;70℃蒸养24 h后,C-S-H/PCE晶种的掺入进一步提高C_(3)S水化产物的生成量并提高微观结构致密性。研究揭示了钙硅摩尔比与温度协同作用对C_(3)S水化产物数量和形貌的调控机制,为C-S-H/PCE晶种合理应用提供参考。 展开更多
关键词 c_(3)s c-s-H/PcE晶种 钙硅比 养护条件 水化产物 微观结构
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