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基于多源检测数据融合的高速铁路路基沉降诊断研究 被引量:2
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作者 赵文博 杨飞 +2 位作者 支洋 尤明熙 胡伟松 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第1期396-405,共10页
高速铁路路基区段受环境变化、地下水开采等因素影响,可能会产生较大幅度的沉降,其中不均匀沉降对高速铁路运行安全、舒适和耐久性影响较大,因此,快速、有效地诊断运营高速铁路路基沉降非常重要。基于列车轨道动态检测数据、车载晃车仪... 高速铁路路基区段受环境变化、地下水开采等因素影响,可能会产生较大幅度的沉降,其中不均匀沉降对高速铁路运行安全、舒适和耐久性影响较大,因此,快速、有效地诊断运营高速铁路路基沉降非常重要。基于列车轨道动态检测数据、车载晃车仪检测数据、台账信息等多源数据,研究不均匀沉降区段的轨道不平顺波长、幅值特征,建立轨道不平顺特征、列车运行速度和列车加速度之间的关联;同时,充分发挥不同数据源的优势,提取波长因子、幅值因子、车体动力响应因子、竖曲线因子、劣化率因子等能够反映路基不均匀沉降特征的指标。利用多源异构数据融合方法,统一各指标当量值,确定各指标融合权重,最终构建高速铁路路基沉降综合评价指标,建立相应计算公式。研究结果表明,路基不均匀沉降会引起较大幅值的轨道几何长波不平顺,进而导致车体加速度超限,并可以通过车载式晃车仪检测;同一区段轨道长波不平顺呈现趋势劣化时能侧面反映沉降的发生,但竖曲线是预先设计的坡度,对路基沉降诊断有一定干扰。路基沉降综合评价指标可以采用百分制,根据现场实践经验,以超过60分作为沉降发生的评判标准。通过3条高速铁路的实际验证,表明本方法能够有效发现路基沉降区段,及时提示工务部门精准维修。 展开更多
关键词 路基沉降 多源数据融合 动态检测 晃车仪
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中草药相关肝损伤的诊断:实践中的挑战
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作者 董一诺 支阳 +1 位作者 唐洁婷 茅益民 《临床肝胆病杂志》 CAS 北大核心 2024年第8期1533-1537,共5页
随着草药和膳食补充剂(HDS)在全球范围内的应用日益广泛,中草药相关肝损伤(HILI)已成为药物性肝损伤的重要病因。由于HILI表现多样、病史采集困难、缺乏特异性生物标志物等原因,如何及时发现疑似患者并建立正确诊断成为实践过程中的主... 随着草药和膳食补充剂(HDS)在全球范围内的应用日益广泛,中草药相关肝损伤(HILI)已成为药物性肝损伤的重要病因。由于HILI表现多样、病史采集困难、缺乏特异性生物标志物等原因,如何及时发现疑似患者并建立正确诊断成为实践过程中的主要难题。目前诊断HILI的过程中多用到因果关系评估,但缺乏大样本前瞻性队列验证。此外,对于HILI诊断的特异性生物标志物仍有待进一步研究。HILI的诊断和鉴别诊断是极具挑战性的问题,目前尚无公认的统一、标准的方法适用于全因HILI的诊断。 展开更多
关键词 中草药 化学性与药物性肝损伤 诊断 因果关系评估 生物标志
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Serum cystatin C,monocyte/high-density lipoprotein-C ratio,and uric acid for the diagnosis of coronary heart disease and heart failure 被引量:1
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作者 Ming Li Da-Hao Yuan +2 位作者 zhi yang Teng-Xiang Luw Xiao-Biao Zou 《World Journal of Clinical Cases》 SCIE 2024年第18期3461-3467,共7页
BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.Howeve... BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.However,conventional diagnostic methods such as electrocardiography,echocardiography,and cardiac biomarkers have certain limitations,such as low sensitivity,specificity,availability,and cost-effectiveness.Therefore,there is a need for simple,noninvasive,and reliable biomarkers to diagnose CHD and HF.AIM To investigate serum cystatin C(Cys-C),monocyte/high-density lipoprotein cholesterol ratio(MHR),and uric acid(UA)diagnostic values for CHD and HF.METHODS We enrolled 80 patients with suspected CHD or HF who were admitted to our hospital between July 2022 and July 2023.The patients were divided into CHD(n=20),HF(n=20),CHD+HF(n=20),and control groups(n=20).The serum levels of Cys-C,MHR,and UA were measured using immunonephelometry and an enzymatic method,respectively,and the diagnostic values for CHD and HF were evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Serum levels of Cys-C,MHR,and UA were significantly higher in the CHD,HF,and CHD+HF groups than those in the control group.The serum levels of Cys-C,MHR,and UA were significantly higher in the CHD+HF group than those in the CHD or HF group.The ROC curve analysis showed that serum Cys-C,MHR,and UA had good diagnostic performance for CHD and HF,with areas under the curve ranging from 0.78 to 0.93.The optimal cutoff values of serum Cys-C,MHR,and UA for diagnosing CHD,HF,and CHD+HF were 1.2 mg/L,0.9×10^(9),and 389μmol/L;1.4 mg/L,1.0×10^(9),and 449μmol/L;and 1.6 mg/L,1.1×10^(9),and 508μmol/L,respectively.CONCLUSION Serum Cys-C,MHR,and UA are useful biomarkers for diagnosing CHD and HF,and CHD+HF.These can provide information for decision-making and risk stratification in patients with CHD and HF. 展开更多
关键词 Serum cystatin C Monocyte/high-density lipoprotein-C ratio Uric acid Coronary heart disease Heart failure Risk stratification
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Anisotropic spin transport and photoresponse characteristics detected by tip movement in magnetic single-molecule junction
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作者 陈登辉 羊志 +5 位作者 付新宇 秦申奥 严岩 王传奎 李宗良 邱帅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期640-648,共9页
Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule junctions.Here,using the first-principles method,we theoretically investigate spin transport properties and p... Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule junctions.Here,using the first-principles method,we theoretically investigate spin transport properties and photoresponse characteristics in trimesic acid magnetic single-molecule junctions with different molecular adsorption orientations and electrode contact sites.The transport calculations indicate that a single-molecule switch and a significant enhancement of spin transport and photoresponse can be achieved when the molecular adsorption orientation changes from planar geometry to upright geometry.The maximum spin polarization of current and photocurrent in upright molecular junctions exceeds 90%.Moreover,as the Ni tip electrode moves,the tunneling magnetoresistance of upright molecular junctions can be increased to 70%.The analysis of the spin-dependent PDOS elucidates that the spinterfaces between organic molecule and ferromagnetic electrodes are modulated by molecular adsorption orientation,where the molecule in upright molecular junctions yields higher spin polarization.Our theoretical work paves the way for designing spintronic devices and optoelectronic devices with anisotropic functionality base on anisotropic molecules. 展开更多
关键词 molecular spintronics spin polarization tunneling magnetoresistance PHOTOCURRENT single-molecule junctions
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Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center
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作者 Wenjing Quan Jia Shi +10 位作者 Min Zeng Wen Lv Xiyu Chen Chao Fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua yang Nantao Hu Tao Wang zhi yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期515-531,共17页
Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption prop... Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas detection.Specifically,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was integrated.The sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 ppb.Simulation analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for NH3.Additionally,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid interface.The sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing signal.Furthermore,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity conditions.This work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research. 展开更多
关键词 Gas sensor Single atom Catalytic activation Targeted adsorption End-sealing passivation
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Overcoming the Limits of Cross-Sensitivity:Pattern Recognition Methods for Chemiresistive Gas Sensor Array
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作者 Haixia Mei Jingyi Peng +4 位作者 Tao Wang Tingting Zhou Hongran Zhao Tong Zhang zhi yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期285-341,共57页
As information acquisition terminals for artificial olfaction,chemiresistive gas sensors are often troubled by their cross-sensitivity,and reducing their cross-response to ambient gases has always been a difficult and... As information acquisition terminals for artificial olfaction,chemiresistive gas sensors are often troubled by their cross-sensitivity,and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing area.Pattern recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas sensors.It is crucial to choose an appropriate pattern recognition method for enhancing data analysis,reducing errors and improving system reliability,obtaining better classification or gas concentration prediction results.In this review,we analyze the sensing mechanism of crosssensitivity for chemiresistive gas sensors.We further examine the types,working principles,characteristics,and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing arrays.Additionally,we report,summarize,and evaluate the outstanding and novel advancements in pattern recognition methods for gas identification.At the same time,this work showcases the recent advancements in utilizing these methods for gas identification,particularly within three crucial domains:ensuring food safety,monitoring the environment,and aiding in medical diagnosis.In conclusion,this study anticipates future research prospects by considering the existing landscape and challenges.It is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications. 展开更多
关键词 Pattern recognition Sensor array Chemiresistive gas sensor CROSS-SENSITIVITY Artificial olfactory
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高速铁路不同轨下基础无砟轨道不平顺谱的构建及对比分析
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作者 刁洪宝 欧燕强 +2 位作者 支洋 赵钢 杨飞 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第7期2840-2855,共16页
为将高速铁路轨道谱细化以应用到不同工况动力学分析中,基于10条设计速度为350 km/h的典型高速线路轨道不平顺动态检测数据及谱构建算法,对高速线路不同轨下基础无砟轨道谱进行构建分析。首先,对动态检测数据进行预处理,并对不同窗函数... 为将高速铁路轨道谱细化以应用到不同工况动力学分析中,基于10条设计速度为350 km/h的典型高速线路轨道不平顺动态检测数据及谱构建算法,对高速线路不同轨下基础无砟轨道谱进行构建分析。首先,对动态检测数据进行预处理,并对不同窗函数、参数模型估计阶数及谱估计算法进行对比分析,选用新矩形窗的改进周期图法计算各类轨道谱,分析谱概率分布特征,提出谱峰自动识别剔除算法并对比不同阶数多项式拟合模型以对随机谱线进行表征,构建CRTSⅠ型、Ⅱ型、Ⅲ型板式及双块式高速铁路路基、桥梁、隧道地段轨道谱,并对各类型不同波段无砟轨道几何状态进行对比分析。研究结果表明:路基、桥梁地段Ⅲ型板线路轨道不平顺状态最优,其次为Ⅱ型板线路、Ⅰ型板线路,双块式随机不平顺状态最差;隧道地段Ⅱ型板线路轨道不平顺状态比双块式的好。 展开更多
关键词 高速铁路 轨道不平顺 功率谱密度 无砟轨道 谱估计方法
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Tracing nitrate sources in one of the world's largest eutrophicated bays(Hangzhou Bay):insights from nitrogen and oxygen isotopes
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作者 zhi yang Jianfang Chen +6 位作者 Haiyan Jin Hongliang Li Zhongqiang Ji yangjie Li Bin Wang Zhenyi Cao Qianna Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期86-95,共10页
Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well understood.In this study,the August 2019 distributi... Eutrophication caused by inputs of excess nitrogen(N) has become a serious environmental problem in Hangzhou Bay(China),but the sources of this nitrogen are not well understood.In this study,the August 2019 distributions of salinity,nutrients [nitrate(NO_(3)^(-)),nitrite,ammonium,and phosphate],and the stable isotopic composition of NO_(3)^(-)(δ^(15)N and δ^(18)O) were used to investigate sources of dissolved inorganic nitrogen(DIN) to Hangzhou B ay.Spatial distributions of nitrate,salinity,and nitrate δ^(18)O indicate that the Qiantang River,the Changjiang River,and nearshore coastal waters may all contribute nitrate to the bay.Based on the isotopic compositions of nitrate in these potential source waters and conservative mixing of nitrate in our study area,we suggest that the NO_(3)^(- )in Hangzhou B ay was likely derived mainly from soils,synthetic N fertilizer,and manure and sewage.End-member modeling indicates that in the upper half of the bay,the Qiantang River was a very important DIN source,possibly contributing more than 50% of DIN in the bay head area.In the lower half of the bay,DIN was sourced mainly from strongly intruding coastal water.DIN coming directly from the Changjiang River made a relatively small contribution to Hangzhou Bay DIN in August 2019. 展开更多
关键词 nitrogen isotopes oxygen isotopes nitrogen cycle nitrate sources Hangzhou Bay
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Enhanced Electrical Properties of Bi_(2−x)Sb_(x)Te_(3) Nanoflake Thin Films Through Interface Engineering
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作者 Xudong Wu Junjie Ding +8 位作者 Wenjun Cui Weixiao Lin Zefan Xue zhi yang Jiahui Liu Xiaolei Nie Wanting Zhu Gustaaf Van Tendeloo Xiahan Sang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期359-366,共8页
The structure–property relationship at interfaces is difficult to probe for thermoelectric materials with a complex interfacial microstructure.Designing thermoelectric materials with a simple,structurally-uniform int... The structure–property relationship at interfaces is difficult to probe for thermoelectric materials with a complex interfacial microstructure.Designing thermoelectric materials with a simple,structurally-uniform interface provides a facile way to understand how these interfaces influence the transport properties.Here,we synthesized Bi_(2−x)Sb_(x)Te_(3)(x=0,0.1,0.2,0.4)nanoflakes using a hydrothermal method,and prepared Bi_(2−x)Sb_(x)Te_(3) thin films with predominantly(0001)interfaces by stacking the nanoflakes through spin coating.The influence of the annealing temperature and Sb content on the(0001)interface structure was systematically investigated at atomic scale using aberration-corrected scanning transmission electron microscopy.Annealing and Sb doping facilitate atom diffusion and migration between adjacent nanoflakes along the(0001)interface.As such it enhances interfacial connectivity and improves the electrical transport properties.Interfac reactions create new interfaces that increase the scattering and the Seebeck coefficient.Due to the simultaneous optimization of electrical conductivity and Seebeck coefficient,the maximum power factor of the Bi_(1.8)Sb_(0.2)Te_(3) nanoflake films reaches 1.72 mW m^(−1)K^(−2),which is 43%higher than that of a pure Bi_(2)Te_(3) thin film. 展开更多
关键词 Bi_(2)Te_(3) nanoflakes interface engineering scanning transmission electron microscopy thermoelectric thin film
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阿司匹林肠溶片的制备及体内外评价
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作者 段丽萍 陈晓雪 +3 位作者 杨志 吴银双 刘峻宇 金笛 《昆明医科大学学报》 CAS 2024年第6期69-74,共6页
目的 制备阿司匹林肠溶片并考察它的体内外释药特性。方法 采用粉末直压法压片,以肠溶材料L30D-55水分散体、滑石粉和枸橼酸三乙酯(1∶1∶0.1)制备阿司匹林肠溶片包衣液固含量为20%,进行肠溶包衣,阿司匹林肠溶片包衣增重范围为15%~20%,... 目的 制备阿司匹林肠溶片并考察它的体内外释药特性。方法 采用粉末直压法压片,以肠溶材料L30D-55水分散体、滑石粉和枸橼酸三乙酯(1∶1∶0.1)制备阿司匹林肠溶片包衣液固含量为20%,进行肠溶包衣,阿司匹林肠溶片包衣增重范围为15%~20%,制得0.1 g阿司匹林肠溶片,即自制制剂(T)。以0.1 g拜阿司匹林肠溶片(Bayaspirin^(R))为参比制剂(R),考察2种制剂的体外释放和体内餐后药动学行为。结果 阿司匹林肠溶片T与R的体外释放曲线f_(2)相似因子均大于50;检测物乙酰水杨酸的C_(max)、AUC_(0-t)和AUC_(0-∞)均满足相应的RSABE或ABE生物等效性评价标准。结论 T与R的体外释放和体内餐后药动学行为具有较好的一致性。 展开更多
关键词 阿司匹林肠溶片 体内外评价 生物等效性 高变异药物
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Complement activation targeted inhibitor C2-FH ameliorates acetaminophen-induced liver injury in mice
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作者 Chun-Mei Li Tian Sun +5 位作者 Mou-Jie yang zhi yang Qing Li Jia-Lin Shi Chong Zhang Jun-Fei Jin 《World Journal of Hepatology》 2024年第10期1188-1198,共11页
BACKGROUND Complement activation is recognized as an important factor in the progression of liver damage caused by acetaminophen(APAP).However,the role of the complement inhibitor C2-FH in APAP-induced liver injury re... BACKGROUND Complement activation is recognized as an important factor in the progression of liver damage caused by acetaminophen(APAP).However,the role of the complement inhibitor C2-FH in APAP-induced liver injury remains unclear.AIM To explore C2-FH in protecting against APAP-induced liver injury by inhibiting complement activation.METHODS A model of APAP-induced liver injury was used to study the protective effect of C2-FH on liver injury.C2-FH was administered through intraperitoneal injection 30 minutes after APAP treatment.We detected the effects of C2-FH on liver function,inflammatory response and complement activation.Additionally,RNA-sequencing(RNA-Seq)analysis was conducted to understand the mechanism through which C2-FH provides protection against APAP-induced liver injury.RESULTS C2-FH inhibited the increase in serum alanine aminotransferase activity,aspartate aminotransferase activity and lactate dehydrogenase,and reduced liver tissue necrosis caused by APAP.Moreover,it attenuated the inflammatory response and inhibited complement activation in APAP-induced liver injury.RNA-Seq analysis provided additional explanations for the protective role of C2-FH against APAP-induced liver injury.CONCLUSION C2-FH attenuates APAP-induced liver injury by inhibiting complement activation. 展开更多
关键词 C2-FH COMPLEMENT Complement activation Acetaminophen-induced liver injury Inflammation
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新工科视域下地方特色轻工行业人才培养路径的探索——以温州大学制笔行业人才培养为例 被引量:2
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作者 王兆伦 王舜 +4 位作者 陈锡安 周敬业 杨植 金辉乐 毕佳捷 《大学化学》 CAS 2023年第3期22-26,共5页
轻工业新工科人才培养是关系国民经济发展和人民生活质量提高的重要课题。本文针对轻工业中尚未设置本科专业的制笔行业人才培养问题,在特色新工科人才培养的产业、技术、学科和人才培育基础上,探索实践了交叉强基、科教强新、产教强能... 轻工业新工科人才培养是关系国民经济发展和人民生活质量提高的重要课题。本文针对轻工业中尚未设置本科专业的制笔行业人才培养问题,在特色新工科人才培养的产业、技术、学科和人才培育基础上,探索实践了交叉强基、科教强新、产教强能的制笔行业新工科人才培养模式,并通过持续改进获得了较好的成效,可为其他高等院校实施特色行业新工科人才培养提供借鉴。 展开更多
关键词 制笔行业 新工科 培养路径 学科交叉 产教融合
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Quantitative and Comprehensive Prediction of Shale Oil Sweet Spots in Qingshankou Formation, Songliao Basin
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作者 Tiantian Wu Xin Bai +9 位作者 Fei Shang Haiyan Zhou Lan Wang Xuexian Zhou zhi Zhong zhi yang Jinyou Zhang Xinyang Cheng Peiyu Zhang Ruiqian Chen 《Journal of Geoscience and Environment Protection》 2023年第5期290-315,共26页
The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”.... The mud shale of Qingshankou Formation in Songliao Basin is the main rock source and contains rich shale oil resources. The successful development of shale oil depends on evaluating and optimizing the “sweet spots”. To accurately identify and optimize the favorable sweet spots of shale oil in Qingshankou Formation, Songliao Basin, the original logging data were preprocessed in this paper. Then the thin mud shale interlayer of Qingshankou Formation was identified effectively by using the processed logging data. Based on the artificial neural network method, the mineral content of mud shale in Qingshankou Formation was predicted. The lithofacies were identified according to the mineral and TOC content. Finally, a three-dimensional (3-D) model of total organic carbon (TOC), vitrinite reflectance (Ro), mineral content, and rock of Qingshankou Formation in Songliao Basin was established to evaluate and predict the favorable sweet spots of shale oil in the study area. The results show that there are a lot of calcareous and siliceous thin interlayers in Qingshankou Formation, and TOC content is generally between 2% and 3%. Ro is the highest in Gulong sag, followed by Sanzhao sag. The lithofacies mainly consists of felsic shale and mixed shale, mainly in the first member of Qingshankou Formation. Comprehensive analysis shows that shale oil development potential is enormous in the eastern part of Sanzhao Sag and the northern part of Gulong Sag. 展开更多
关键词 Songliao Basin Qingshankou Formation Shale Oil Sweet Spot Artificial Neural Network
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考虑周期性不平顺的高速铁路各型无砟轨道谱拟合与反演方法 被引量:2
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作者 杨飞 孙宪夫 +3 位作者 尤明熙 支洋 王琰 肖军华 《铁道学报》 EI CAS CSCD 北大核心 2023年第9期114-122,共9页
轨道不平顺是轮轨相互作用的激扰源,其周期性特性是除波长、幅值外不可忽视的特征。结合大量动检数据,提出考虑周期性不平顺的高速铁路各型无砟轨道谱拟合与反演方法,结果表明:高速铁路周期性不平顺根据轨下基础结构尺寸、钢轨状态等诱... 轨道不平顺是轮轨相互作用的激扰源,其周期性特性是除波长、幅值外不可忽视的特征。结合大量动检数据,提出考虑周期性不平顺的高速铁路各型无砟轨道谱拟合与反演方法,结果表明:高速铁路周期性不平顺根据轨下基础结构尺寸、钢轨状态等诱因分为9类。提出采用修正的高斯函数表征周期性不平顺,基于8阶多项式拟合无砟轨道谱,结合谱反演验证周期性不平顺表征的合理性。通过拟合谱发现,CRTSⅢ型板的随机不平顺状态最优,CRTSⅠ型板最差。CRTSⅡ型板与双块式的随机不平顺状态相当,这两种板型轨道谱在大多数波段介于CRTSⅠ型板和CRTSⅢ型板之间,与高速铁路无砟轨道谱的分布特征最为接近。 展开更多
关键词 周期性不平顺 无砟轨道谱 高斯函数 多项式拟合 功率谱密度
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Development of a CLDN18.2-targeting immuno-PET probe for non-invasive imaging in gastrointestinal tumors 被引量:7
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作者 Yan Chen Xingguo Hou +11 位作者 Dapeng Li Jin Ding Jiayue Liu Zilei Wang Fei Teng Hongjun Li Fan Zhang Yi Gu Steven Yu Xueming Qian zhi yang Hua Zhu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第4期367-375,共9页
Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential b... Claudin18.2(CLDN18.2)is a tight junction protein that is overexpressed in a variety of solid tumors such as gastrointestinal cancer and oesophageal cancer.It has been identified as a promising target and a potential biomarker to diagnose tumor,evaluate efficacy,and determine patient prognosis.TST001 is a recombinant humanized CLDN18.2 antibody that selectively binds to the extracellular loop of human Claudin18.2.In this study,we constructed a solid target radionuclide zirconium-^(89)(^(89)Zr)labled-TST001 to detect the expression of in the human stomach cancer BGC823CLDN18.2 cell lines.The[^(89)Zr]Zr-desferrioxamine(DFO)-TST001 showed high radiochemical purity(RCP,>99%)and specific activity(24.15±1.34 GBq/mmol),and was stable in 5%human serum albumin,and phosphate buffer saline(>85%RCP at 96 h).The EC_(50) values of TST001 and DFO-TST001 were as high as 0.413±0.055 and 0.361±0.058 nM(P>0.05),respectively.The radiotracer had a significantly higher average standard uptake values in CLDN18.2-positive tumors than in CLDN18.2-negative tumors(1.11±0.02 vs.0.49±0.03,P=0.0016)2 days post injection(p.i.).BGC823CLDN18.2 mice models showed high tumor/muscle ratios 96 h p.i.with[^(89)Zr]Zr-DFO-TST001 was much higher than those of the other imaging groups.Immunohistochemistry results showed that BGC823CLDN18.2 tumors were highly positive(+++)for CLDN18.2,while those in the BGC823 group did not express CLDN18.2().The results of ex vivo biodistribution studies showed that there was a higher distribution in the BGC823CLDN18.2 tumor bearing mice(2.05±0.16%ID/g)than BGC823 mice(0.69±0.02%ID/g)and blocking group(0.72±0.02%ID/g).A dosimetry estimation study showed that the effective dose of[^(89)Zr]Zr-DFO-TST001 was 0.0705 mSv/MBq,which is within the range of acceptable doses for nuclear medicine research.Taken together,these results suggest that Good Manufacturing Practices produced by this immuno-positron emission tomography probe can detect CLDN18.2-overexpressing tumors. 展开更多
关键词 Claudin18.2 Gastrointestinal cancers Zirconium-89 Positron emission tomography Good Manufacturing Practices
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高速铁路路基沉降对车体振动影响研究 被引量:5
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作者 高雅 尤明熙 +4 位作者 杨飞 支洋 张瑶 赵文博 李威霖 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2023年第4期1139-1148,共10页
某开通时间较短的高速铁路线路受连续降雨影响,路基沉降快速发展,导致部分区段轨道结构发生变形,使轨道不平顺幅值明显增加,引起车体振动加剧,对列车运行的安全性和稳定性造成影响。为了研究路基沉降引起的轨道不平顺对车体振动的影响,... 某开通时间较短的高速铁路线路受连续降雨影响,路基沉降快速发展,导致部分区段轨道结构发生变形,使轨道不平顺幅值明显增加,引起车体振动加剧,对列车运行的安全性和稳定性造成影响。为了研究路基沉降引起的轨道不平顺对车体振动的影响,选取典型路基沉降区段连续4次动态检测数据进行时频特征分析,结合建立的车辆-有砟轨道空间耦合动力学仿真模型,研究路基沉降区段轨道不平顺和车体振动加速度之间的映射关系,获得了路基沉降不平顺波长和状态演变对车辆动力响应的影响规律。研究结果表明:降雨导致的路基沉降对高低不平顺和车体垂向加速度的影响显著,对轨向不平顺和车体横向加速度的影响较小;路基沉降区段的高低不平顺与车体垂向加速度幅值变化趋势和振动频率基本相同,42~70 m波长高低不平顺的幅值增加是造成车体垂向振动加剧的主要原因;依据仿真结果,路基沉降引起的高低不平顺幅值急剧增加会造成行车过程中局部轮轨垂向力显著减小,导致轮重减载率显著增加;对于速度等级250 km/h的线路,建议雨后重点盯控路基沉降点长波高低不平顺的变化,针对车体垂向振动加速度不良区段的养护维修作业,应着重调整42~70 m波长高低不平顺幅值,以保障车辆安全稳定运营。 展开更多
关键词 高速铁路 轨道不平顺 车体振动 车辆-轨道耦合 动力响应
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Outstanding Humidity Chemiresistors Based on Imine-Linked Covalent Organic Framework Films for Human Respiration Monitoring 被引量:4
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作者 Xiyu Chen Lingwei Kong +9 位作者 Jaafar Abdul-Aziz Mehrez Chao Fan Wenjing Quan Yongwei Zhang Min Zeng Jianhua yang Nantao Hu Yanjie Su Hao Wei zhi yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期368-383,共16页
Human metabolite moisture detection is important in health monitoring and non-invasive diagnosis.However,ultra-sensitive quantitative extraction of respiration information in real-time remains a great challenge.Herein... Human metabolite moisture detection is important in health monitoring and non-invasive diagnosis.However,ultra-sensitive quantitative extraction of respiration information in real-time remains a great challenge.Herein,chemiresistors based on imine-linked covalent organic framework(COF)films with dual-active sites are fabricated to address this issue,which demonstrates an amplified humidity-sensing signal performance.By regulation of monomers and functional groups,these COF films can be pre-engineered to achieve high response,wide detection range,fast response,and recovery time.Under the condition of relative humidity ranging from 13 to 98%,the COFTAPB-DHTA film-based humidity sensor exhibits outstanding humidity sensing perfor-mance with an expanded response value of 390 times.Furthermore,the response values of the COF film-based sensor are highly linear to the relative humidity in the range below 60%,reflecting a quantitative sensing mechanism at the molecular level.Based on the dual-site adsorption of the(-C=N-)and(C-N)stretching vibrations,the revers-ible tautomerism induced by hydrogen bonding with water molecules is demonstrated to be the main intrinsic mechanism for this effective humidity detection.In addition,the synthesized COF films can be further exploited to effectively detect human nasal and oral breathing as well as fabric permeability,which will inspire novel designs for effective humidity-detection devices. 展开更多
关键词 Covalent organic frameworks Humidity sensors Reversible tautomerism Non-invasive diagnosis Health monitoring
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Recent advances and key opportunities on in-plane micro-supercapacitors:From functional microdevices to smart integrated microsystems 被引量:1
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作者 Jieqiong Qin Hongtao Zhang +4 位作者 zhi yang Xiao Wang Pratteek Das Feng Zhou Zhong-Shuai Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期410-431,I0010,共23页
The popularization of portable,implantable and wearable microelectronics has greatly stimulated the rapid development of high-power planar micro-supercapacitors(PMSCs).Particularly,the introduction of new functionalit... The popularization of portable,implantable and wearable microelectronics has greatly stimulated the rapid development of high-power planar micro-supercapacitors(PMSCs).Particularly,the introduction of new functionalities(e.g.,high voltage,flexibility,stretchability,self-healing,electrochromism and photo/thermal response)to PMSCs is essential for building multifunctional PMSCs and their smart selfpowered integrated microsystems.In this review,we summarized the latest advances in PMSCs from various functional microdevices to their smart integrated microsystems.Primarily,the functionalities of PMSCs are characterized by three major factors to emphasize their electrochemical behavior and unique scope of application.These include but are not limited to high-voltage outputs(realized through asymmetric configuration,novel electrolyte and modular integration),mechanical resilience that includes various feats of flexibility or stretchability,and response to stimuli(self-healing,electrochromic,photo-responsive,or thermal-responsive properties).Furthermore,three representative integrated microsystems including energy harvester-PMSC,PMSC-energy consumption,and all-in-one selfpowered microsystems are elaborately overviewed to understand the emerging intelligent interaction models.Finally,the key perspectives,challenges and opportunities of PMSCs for powering smart microelectronics are proposed in brief. 展开更多
关键词 Micro-supercapacitors IN-PLANE Functionalization Integrated microsystem Energy storage
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Inspired by novel radiopharmaceuticals:Rush hour of nuclear medicine 被引量:1
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作者 yang Liu Ya-nan Ren +4 位作者 Yan Cui Song Liu zhi yang Hua Zhu Nan Li 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2023年第5期470-482,共13页
Nuclear medicine plays an irreplaceable role in the diagnosis and treatment of tumors.Radiopharmaceuticals are important components of nuclear medicine.Among the radiopharmaceuticals approved by the Food and Drug Admi... Nuclear medicine plays an irreplaceable role in the diagnosis and treatment of tumors.Radiopharmaceuticals are important components of nuclear medicine.Among the radiopharmaceuticals approved by the Food and Drug Administration(FDA),radio-tracers targeting prostate-specific membrane antigen(PSMA)and somatostatin receptor(SSTR)have held essential positions in the diagnosis and treatment of prostate cancers and neuroendocrine neoplasms,respectively.In recent years,FDA-approved serials of immune-therapy and targeted therapy drugs targeting programmed death 1(PD-1)/programmed death ligand 1(PD-L1),human epidermal growth factor receptor 2(HER2),and nectin cell adhesion molecule 4(Nectin 4).How to screen patients suitable for these treatments and monitor the therapy?Nuclear medicine with specific radiopharmaceuticals can visualize the expression level of those targets in systemic lesions and evaluate the efficacy of treatment.In addition to radiopharmaceuticals,imaging equipment is also a key step for nuclear medicine.Advanced equipment including total-body positron emission tomography/computed tomography(PET/CT)and positron emission tomography/magnetic resonance imaging(PET/MRI)has been developed,which contribute to the diagnosis and treatment of tumors,as well as the development of new radiopharmaceuticals.Here,we conclude most recently advances of radiopharmaceuticals in nuclear medicine,and they substantially increase the“arsenal”of clinicians for tumor therapy. 展开更多
关键词 Nuclear medicine RADIOPHARMACEUTICALS NEOPLASMS
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L型钙离子通道α1D亚基基因多态性对苯磺酸氨氯地平治疗老年高血压患者效果的影响 被引量:1
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作者 支杨 衡薇 +5 位作者 王克宇 袁欣根 康丝雨 于春霞 郭海东 刘思思 《标记免疫分析与临床》 CAS 2023年第12期1986-1990,共5页
目的探讨L型钙离子通道α1D亚基基因CACNA1D基因多态性对苯磺酸氨氯地平治疗老年原发高血压临床疗效的影响。方法选取2021年1月至2022年5月就诊于北京市西城区广外医院的101例老年原发高血压患者,7∶00 am口服苯磺酸氨氯地平5mg/d治疗8... 目的探讨L型钙离子通道α1D亚基基因CACNA1D基因多态性对苯磺酸氨氯地平治疗老年原发高血压临床疗效的影响。方法选取2021年1月至2022年5月就诊于北京市西城区广外医院的101例老年原发高血压患者,7∶00 am口服苯磺酸氨氯地平5mg/d治疗8周,采集体质指数(BMI)、收缩压(SBP)、舒张压(DBP)信息。并检测尿素(Urea)、肌酐(Cr)、血糖(Glu)等指标。通过DNA提取和PCR扩增进行CACNA1D基因分型(rs312481、rs3774426、rs219847位点)。结果不同基因型患者(rs312481、rs3774426、rs219847位点)BMI及Urea等一般临床指标比较,差异无统计学意义(P>0.05)。rs312481的GG型舒张压降幅大于GA组,差异具有统计学意义(P<0.05),但与AA型比较无统计学差异(P>0.05)。rs219847中,GG组收缩压和舒张压降幅均大于GA组和AA组,且rs3774426中CT组收缩压和CC组舒张压降幅大于另外两组,但差异无统计学意义(P>0.05)。结论在氨氯地平治疗老年高血压患者中,CACNA1D基因rs312481位点GG型携带者相对于GA型可能会有更好的疗效。 展开更多
关键词 老年原发性高血压 CACNA1D基因多态性 钙离子通道阻滞剂
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