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Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： Jian li Wen Yi XiangHui xue Jie Zeng HaiLun Ye JianYuan Wang JinSong Chen Na li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

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Enhanced subacute ischemic stroke treatment via multistage drug delivery system design for combination therapy

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Science China Chemistry 2025年

作者： Xihan Xu Juan-Juan li Jiamin li Hui-Yan Zhang Yilin Qi Bing-Sen Shi Tianqi li Shan-Shan Su Weitao Zhao Chang Chen Zhongying Gong Huiyu liu Ke-Rang Wang Dong-Sheng Guo xue xue State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University College of Chemistry State Key Laboratory of Elemento-Organic Chemistry Key Laboratory of Functional Polymer Materials (Ministry of Education) Frontiers Science Center for New Organic Matter Collaborative Innovation Center of Chemical Science and EngineeringNankai University College of Chemistry and Materials Science State Key Laboratory of New Pharmaceutical Preparations and Excipients Key Laboratory of Medicinal Chemistry and Molecular Diagnosis (Ministry of Education) Key Laboratory of Chemical Biology of Hebei Province Hebei Research Center of the Basic Discipline of Synthetic Chemistry Hebei University Department of Neurology Tianjin First Central Hospital School of Medicine Nankai University Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic Composites Beijing Laboratory of Biomedical Materials Bionanomaterials & Translational Engineering Laboratory Beijing Key Laboratory of BioprocessBeijing University of Chemical Technology

The management of acute ischemic stroke remains challenging due to its abrupt onset and the narrow treatment window,resulting in high rates of disability and *** therapy for neuroprotection and neurorepair strategies provided new hopes for subacute stroke *** we designed a multistage nanodelivery system that matches the unique microenvironment of the subacute phase of stroke,which utilizes calixarene as a building block to effectively load the neuroprotective drug *** calixarene is designed with glycosidic linkages targeting the glucose transporter 1 (GLUT1)on the blood-brain barrier (BBB) and azo bonds that are responsive to hypoxic ***,the decomposed calixarene molecules themselves possess intrinsic bio-activation to modulate inflammatory responses,achieving a multistage therapeutic approach that transitions from targeting to release and finally to *** approach combines anti-inflammation and neuroprotection,providing a multi-level treatment *** system was validated in a rat model of permanent middle cerebral artery occlusion (pMCAO),demonstrating that intravenous administration of the nanodelivery system repairs brain damage and improves motor function 24 h post-pMCAO *** work offers a precise and integrative strategy for stroke patients missing the acute therapy window to improve functional recovery and enhance the effect of comprehensive treatment.

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High-selectivity electroreduction of low-concentration CO2 with large concentration fluctuation

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Science China Chemistry 2025年

作者： Mengyu Qi Yanbin Ma Chao Zhang Bingwei li xueqing Yang Zhaolin Shi Simeng liu Changhua An Jiqing jiao Tongbu Lu MOE International Joint Laboratory of Materials Microstructure Analysis and Testing CenterInstitute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringSchool of Chemistry and Chemical EngineeringTianjin University of Technology Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University

Electrochemical CO2reduction reaction（CO2RR） has been regarded as one of the most promising solutions to achieving “zero carbon emission”. In most of the CO2RR-related studies, high-purity CO2has been employed as the feed gas; however, in practice, CO2is generally emitted in low concentrations, so it is of great significance to realize high-selectivity electroreduction of low-concentration CO2with large concentration fluctuation. In this work, we constructed a dual-active-site catalyst and successfully achieved CO2local enrichment and conversion for low-concentration CO2. Operando experiments reveal that the catalyst has one type of site for activating CO2and one type of site for binding the reaction intermediates. The dual-active-site catalyst displays a selectivity for formic acid consistently above 97% over a broad potential window（from-0.9 to-1.6 V ***）. Even when fed with a low-concentration CO2stream（volume ratio from 50% down to 10%）, the dual-active-site catalyst could display high activity and selectivity（>91%）. In particular, the selectivity is still above 85% when the CO2volume ratio is as low as 5%. This work offers a feasible route for converting low-concentration CO2via a synergistic effect for dual-active-site catalysts.

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High-precision magnetic field measurement system based on a coherent population trapping magnetometer onboard the SATech-01 satellite

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Science China Technological Sciences 2025年

作者： Hongbo xue Wei SONG Haoran ZHAO Yiteng ZHANG Shanzhi YE Jindong WANG Ran TAO Peng SANG Keli CHEN Xingzi BI Bingjun CHENG Bin ZHOU Yongliang xue Yingying TANG liu liU Jinsong li Xiaocheng ZHU Baoquan li Jinguo liU Wen CHEN Xiaofeng ZHANG Yonghe ZHANG Lei li State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Solar Activity and Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Electronics and Information Technology for Space Systems National Space Science Center Chinese Academy of Sciences State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Innovation Academy for Microsatellites Chinese Academy of Sciences

On July 27, 2022, a high-precision system for measuring the magnetic field based on a coherent population trapping magnetometer（referred to as the CPT system） was launched onboard the Space Advanced Technology demonstration satellite（SATech-01） by a ZK-1A rocket. The payload comprises a scalar coherent population trapping magnetometer（CPTM）, triaxial anisotropic magnetoresistance magnetometer（AMRM）, and nano star tracker mounted on a non-magnetic telescopic tubular mast. This configuration enables synchronized measurement of scalar and vector geomagnetic fields, as well as the attitude,making the payload with its compact sensors suitable for applications on miniature satellite platforms. On November 7, 2022,the novel telescopic tubular mast was deployed in orbit, extending to a length of 5.28 m. The CPTM, an absolute scalar magnetometer with an omnidirectional sensor, is the first China-developed quantum/atomic magnetometer successfully operating in space. In orbit, the CPTM has sensitivity of ～10 pT/Hz1/2and can automatically operate under complex magnetic field variations. The difference between the scalar fields obtained using the CPTM and CHAOS model has a mean deviation of–3.73 n T and a standard deviation of 26.11 nT（1σ）, without on-orbit calibration or correction. The miniaturized AMRM has a sensitivity of ～0.3 n T/Hz1/2and maintains stable and reliable operation in orbit. The low-power and miniaturized nano star tracker has a measurement uncertainty of 14.23″（1σ） in orbit. The mission has realized the on-orbit technical verification of the integrated and synchronized detection of the vector magnetic field and attitude and fully validated the system's performance,automation level, and reliability.

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石灰-粉煤灰改良汉中膨胀土试验研究

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陕西理工学院学报（自然科学版） 2010年第1期26卷 36-38,43页

作者：林友军薛丽皎陈丽红陕西理工学院土木工程与建筑系陕西汉中723001

通过对膨胀土掺和石灰-煤粉灰进行改性试验,研究了汉中膨胀土改性前后胀缩性、强度等性能的变化,得到了膨胀土掺和石灰-粉煤灰进行改良的最佳掺量为质量分数石灰8%,粉煤灰16%,将为汉中膨胀土治理提供参考。

关键词：膨胀土改良最佳掺灰率

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骨料对透水混凝土性能的影响

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陕西理工学院学报（自然科学版） 2010年第1期26卷 29-31页

作者：薛丽皎陈丽红林友军陕西理工学院土建系陕西汉中723001

试验研究了骨料品种、骨料粒径对透水混凝土主要性能的影响。试验结果表明:在相同骨料粒径的情况下,由碎石骨料配置的透水混凝土总孔隙率和透水系数明显大于卵石骨料配置的透水混凝土,碎石的强度变化幅度比卵石的变化幅度明显;随着骨料... 详细信息

试验研究了骨料品种、骨料粒径对透水混凝土主要性能的影响。试验结果表明:在相同骨料粒径的情况下,由碎石骨料配置的透水混凝土总孔隙率和透水系数明显大于卵石骨料配置的透水混凝土,碎石的强度变化幅度比卵石的变化幅度明显;随着骨料粒径的增大两种骨料配置的透水混凝土的孔隙率、透水系数均有所增大,在同一配合比情况下,随着骨料粒径的增大透水混凝土的强度呈非线性变化,且存在最佳粒径尺寸。

关键词：透水混凝土骨料品种骨料粒径主要性能

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石灰改性汉中膨胀土试验研究

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陕西理工学院学报（自然科学版） 2010年第4期26卷 38-41,57页

作者：薛丽皎陈丽红林友军陕西理工学院土木建筑与工程系陕西汉中723001

试验以石灰作为外掺料,对汉中中、强两种膨胀土进行了以界限含水量、自由膨胀率和强度等为指标的改性对比试验。试验表明:在不同掺灰剂量、不同龄期作用下,石灰对强膨胀土界限含水量的改性效果相对明显,其改性效果存在一个限值。掺灰量... 详细信息

试验以石灰作为外掺料,对汉中中、强两种膨胀土进行了以界限含水量、自由膨胀率和强度等为指标的改性对比试验。试验表明:在不同掺灰剂量、不同龄期作用下,石灰对强膨胀土界限含水量的改性效果相对明显,其改性效果存在一个限值。掺灰量在6%左右时,两种膨胀土改良效果较好。在严格按照施工规范和控制技术标准进行现场掺料时,可适当缩短闷料时间。

关键词：膨胀土石灰改性最优掺灰量龄期

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肝切除、射频消融和肝移植三种方案治疗小肝癌的临床疗效比较

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实用医药杂志 2018年第3期35卷 193-196页

作者：矫学黎陈燚李霞陈建锋解放军401医院肝胆外科山东青岛266071 解放军401医院影像科山东青岛266071 海军青岛第一疗养院特检科山东青岛266071

目的对小肝癌(小肝细胞癌)的3种常用外科治疗方法进行疗效比较,为小肝癌的临床治疗方案选择提供参考。方法选取2006年1月—2015年12月解放军401医院外科治疗的660例小肝癌病例进行研究。根据肿瘤直径分为0~2.0 cm、2.1~3.0 cm、3.1~5.0... 详细信息

目的对小肝癌(小肝细胞癌)的3种常用外科治疗方法进行疗效比较,为小肝癌的临床治疗方案选择提供参考。方法选取2006年1月—2015年12月解放军401医院外科治疗的660例小肝癌病例进行研究。根据肿瘤直径分为0~2.0 cm、2.1~3.0 cm、3.1~5.0 cm和多发组,根据治疗方案分为肝切除组、射频消融组和肝移植组。比较各组之间整体生存时间和整体生存率、无瘤生存时间和无瘤生存率的差异。结果在0~2.0 cm组和2.1~3.0 cm组中,肝切除和射频消融的疗效相当,而肝移植的疗效优于肝切除和射频消融(P<0.05);在3.1~5.0 cm组中,肝移植的疗效最优,肝切除次之,射频消融效果最差(P<0.05);在多发组中,肝切除和射频消融的疗效相当,而肝移植的疗效优于肝切除和射频消融(P<0.05)。结论小肝癌瘤体的直径和数目对治疗方案的选择具有重要的临床意义,其中肝移植治疗小肝癌疗效最佳。

关键词：小肝癌肝切除射频消融肝移植

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高温作用后再生粗骨料特征性能试验研究

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陕西工学院学报 2005年第2期21卷 48-49,55页

作者：薛丽皎陈丽红林友军陕西理工学院土木工程与建筑系陕西汉中723003

将高温作用后的废弃混凝土经破碎、分解作为混凝土的再生粗骨料,针对再生粗骨料的特征性能进行了一系列的试验研究。试验表明:影响再生粗骨料吸水率的有作用温度、表面粗糙度、粒径和内部缺陷等因素;分析了骨料的压碎指标与基本性能受... 详细信息

将高温作用后的废弃混凝土经破碎、分解作为混凝土的再生粗骨料,针对再生粗骨料的特征性能进行了一系列的试验研究。试验表明:影响再生粗骨料吸水率的有作用温度、表面粗糙度、粒径和内部缺陷等因素;分析了骨料的压碎指标与基本性能受高温作用的影响规律,为配制再生混凝土提供必要依据。

关键词：高温作用再生粗骨料特征性能影响因素

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融合语义特征的加权朴素贝叶斯分类算法

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计算机工程与设计 2020年第9期41卷 2523-2529页

作者：邱宁佳贺金彪薛丽娇王鹏赵建平长春理工大学计算机科学技术学院吉林长春130022

针对传统朴素贝叶斯算法属性独立性假设降低分类效果的问题,提出一种融合语义特征的加权朴素贝叶斯算法。在特征提取时引入Google距离衡量词语间语义相关性对节点权值进行重新计算;利用改进的NGD-TextRank算法提取数据集中关键特征,去... 详细信息

针对传统朴素贝叶斯算法属性独立性假设降低分类效果的问题,提出一种融合语义特征的加权朴素贝叶斯算法。在特征提取时引入Google距离衡量词语间语义相关性对节点权值进行重新计算;利用改进的NGD-TextRank算法提取数据集中关键特征,去除冗余属性进行降维;在分类过程中对不同特征项的影响程度进行划分,将特征项的权值融合到朴素贝叶斯公式中构造加权朴素贝叶斯分类算法。为验证算法性能,使用多类型数据集设计实验,与同类算法对比分析结果表明,该算法能够有效提取关键特征,经过加权处理后较好提高了文本分类的准确性。

关键词： Google距离 TextRank Hellinger距离权值优化朴素贝叶斯

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