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Low-temperature(NO + O_(2)) adsorption performance of alkaline earth metal-doped C-FDU-15

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Journal of Environmental Sciences 2021年第5期33卷 172-184页

作者： Runping Wu qing ye Kai Wu Hongxing Dai Key Laboratory of Beijing on Regional Air Pollution Control Department of Environmental ScienceCollege of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of Chinaand Laboratory of Catalysis Chemistry and NanoscienceDepartment of Chemistry and Chemical EngineeringCollege of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

To improve the removal capacity of NO + O_(2) effectively, the alkaline earth metal-doped order mesoporous carbon(A-C-FDU-15(0.001)(A = Mg, Ca, Sr and Ba)) and Mg-C-FDU-15( x)( x = 0.001-0.003) samples were prepared, and their physicochemical and NO + O_(2) adsorption properties were determined by means of various techniques. The results show that the sequence in(NO + O_(2)) adsorption performance was as follows: Mg-C-FDU-15(0.001)(93.2 mg/g) > Ca-C-FDU-15(0.001)(82.2 mg/g) > Sr-C-FDU-15(0.001)(76.1 mg/g) > Ba-C-FDU-15(0.001)(72.9 mg/g) > C-FDU-15(67.1 mg/g). Among all of the A-C-FDU-15(0.001) samples, Mg-C-FDU-15(0.001) possessed the highest(NO + O_(2)) adsorption capacity(106.2 mg/g). The species of alkaline earth metals and basic sites were important factors determining the adsorption of NO + O_(2) on the A-C-FDU-15( x) samples, and(NO + O_(2)) adsorption on the samples was mainly chemical adsorption. Combined with the results of(NO + O_(2))-temperatureprogrammed desorption((NO + O_(2))-TPD) and in situ diffused reflectance infrared Fourier transform spectroscopy(DRIFTS) characterization, we deduced that there were two main pathways of(NO + O_(2)) adsorption: one was first the conversion of NO and O_(2) to NO_(2) and then part of NO_(2) was converted to NO_(2)^(-) and NO_(3)^(-);and the other was the direct oxidation of NO to NO-2 and NO_(3)^(-).

关键词： C-FDU-15 Alkaline earth metal NO+O_(2)adsorption Adsorption mechanism Adsorption kinetics

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紫色土坡耕地耕层持水抗旱性能及生产力对侵蚀程度的响应

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中国农业科学 2024年第7期57卷 1350-1362页

作者：倪书辉史东梅盘礼东叶青伍俊豪西南大学资源环境学院

【目的】分析侵蚀条件下紫色土坡耕地耕层持水性能与产量响应特征，为调控坡耕地季节性干旱及水分利用效率、提升侵蚀条件下坡耕地玉米产量提供理论依据。【方法】采用铲土侵蚀模拟法，以未侵蚀地块为对照组（S-0），对比分析5 cm(S-5)... 详细信息

【目的】分析侵蚀条件下紫色土坡耕地耕层持水性能与产量响应特征，为调控坡耕地季节性干旱及水分利用效率、提升侵蚀条件下坡耕地玉米产量提供理论依据。【方法】采用铲土侵蚀模拟法，以未侵蚀地块为对照组（S-0），对比分析5 cm(S-5)、10 cm(S-10)、15 cm(S-15)、20 cm(S-20)侵蚀程度和3种管理措施下（不施肥（CK）、施化肥（F）、生物炭+化肥（BF）），坡耕地耕层持水抗旱性能和玉米产量的年际变化特征及对侵蚀程度的响应。【结果】（1）坡耕地心土层土壤持水性能更强。在相同水平土壤水吸力下，耕作层土壤容积含水量降低幅度（13.9%—18.2%）较心土层更大（9.8%）；随年际变化，土壤容积含水量在S-5时增幅最大为耕作层（14.2%），而心土层表现为在S-15最大（33.2%）。（2）坡耕地土壤总库容、兴利库容、最大有效库容及有效水分含量，随侵蚀加剧呈开口朝下的抛物线变化规律。随年际变化，各侵蚀程度下土壤最大有效库容最大增幅（44.7%）处于较强烈侵蚀程度（S-15），而有效水分含量、最大储水量及单次接纳最大降雨量在微弱侵蚀程度下（S-0至S-10）提升幅度最大。（3）坡耕地玉米产量随侵蚀加剧总体呈降低趋势，且与土壤最大有效库容、田间持水量有正相关关系；随年际变化，各侵蚀程度下坡耕地减产效果降低，且产量变化随侵蚀加剧呈一定滞后性，即侵蚀发生年产量无明显减产。（4）侵蚀条件下坡耕地土壤最大有效库容主要受土壤质地中黏粒含量、毛管孔隙度和有机质含量显著影响（P<0.01）；而田间持水量与土层深度、有机质、粉粒及孔隙度呈极显著关系（P<0.01）。【结论】土壤持水抗旱性能的强弱主要受土壤结构优劣的影响。对坡耕地侵蚀耕层辅以深翻耕作和生物炭+化肥管理措施改善土壤结构，可有效调控坡耕地侵蚀性耕层持水抗旱性能，提升侵蚀条件下坡耕地作物产量。

关键词：紫色土坡耕地持水性能抗旱性能土壤侵蚀土壤库容玉米

Electron-beam radiation effects on the structure and properties of polypropylene at low dose rates

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Nuclear Science and Techniques 2018年第6期29卷 101-109页

作者： heng-Ti Wang Hai-qing Jiang Rong-Fang Shen Xiao-Jun Ding Cong Zhang Lin-Fan Li Jing-ye Li Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China

While the high-energy radiation effects on polypropylene, which are crucial for the cable industry for nuclear power plants, have been thoroughly studied, the property changes of PP at low-dose-rate electron-beam irradiation are far from elucidated. Herein, the influence of electron-beam irradiation on the structure and properties of PP was examined. The static EB irradiation conditions were 1.2 MeV at a low dose rate of 20 kGy/h to achieve absorbed doses ranging from 45, to 60, 100, and 200 *** molecular structure was first evaluated by measuring the carboxyl index and the relative radical concentrations via Fourier transform infrared spectroscopy and electron spin resonance, respectively. Mechanical, differential scanning colorimetric, and rheological tests were carried out to further investigate the changes in the properties(tensile, crystalizing, and viscoelastic properties) of irradiated PP, which showed good agreement with the structural analysis results. We found that radio-oxidative degradation(chain scission) was predominant, which can be due to the low dose rate facilitating oxygen diffusion into the PP matrix during electron-beam irradiation.

关键词：性质变化低剂量率聚丙烯电子横梁结构放射 Fourier

Contribution of diffusion,perfusion and functional MRI to the disconnection hypothesis in subcortical vascular cognitive impairment

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Stroke & Vascular Neurology 2018年第3期3卷 131-139页

作者： qing ye Feng Bai Department of Neurology Affiliated Drum Tower HospitalNanjing University Medical SchoolNanjingJiangsuChina Jiangsu Province Stroke Center for Diagnosis and Therapy NanjingChina Nanjing Neuropsychiatry Clinic Medical Center NanjingChina Jiangsu Key Laboratory for Molecular Medicine Nanjing University Medical SchoolNanjingChina

Vascular cognitive impairment(VCI)describes all forms of cognitive impairment caused by any type of cerebrovascular *** identification of VCI is quite difficult due to the lack of both sensitive and specific *** damage to the white matter tracts,which connect the cortical and subcortical regions,has been shown in subcortical VCI(SVCI),the most common subtype of VCI that is caused by small vessel *** specific MRI sequences,including diffusion tensor imaging(DTI)and functional MRI(fMRI),have emerged as useful tools for identifying subtle white matter changes and the intrinsic connectivity between distinct cortical *** review describes the advantages of these two modalities in SVCI research and the current DTI and fMRI findings on *** DTI technique,a variety of studies found that white matter microstructural damages in the anterior and superior areas are more specific to ***,functional brain abnormalities detected by fMRI have also been mainly shown in anterior brain areas in *** characteristic distribution of brain abnormalities in SVCI interrupts the prefrontal-subcortical loop that results in cognitive impairments in particular domains,which further confirms the‘disconnection syndrome’*** addition,another MRI technique,arterial spin labelling(ASL),has been used to describe the disconnection patterns in a variety of conditions by measuring cerebral blood *** role of the ASL technique in SVCI research is also ***,the review proposes the application of multimodality fusion in the investigation of SVCI pathogenesis.

关键词： impairment subcortical diffusion

基于内聚力模型的嵌岩双斜桩水平承载特性分析

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岩土工程学报 2024年第S1期46卷 233-238页

作者：叶青郭伟任宇晓庄道坤崔赛月天津大学建筑工程学院天津300072 滨海土木工程结构与安全教育部重点实验室(天津大学) 天津300072

基于已有的对桩-岩界面剪切特性的研究,建立了界面几何参数和材料特性与内聚力模型参数间的转换关系,与现场试验和理论研究对比,验证了接触模型的准确性;结合室内嵌岩双斜桩模型试验,建立了对应有限元数值计算模型,对比分析了桩基荷载-... 详细信息

基于已有的对桩-岩界面剪切特性的研究,建立了界面几何参数和材料特性与内聚力模型参数间的转换关系,与现场试验和理论研究对比,验证了接触模型的准确性;结合室内嵌岩双斜桩模型试验,建立了对应有限元数值计算模型,对比分析了桩基荷载-位移曲线与弯矩规律,验证了模型的可靠性;进而建立不同倾角的足尺嵌岩双斜桩模型,分析在不同竖向定荷载下的水平承载特性。研究表明:嵌岩双斜桩系统是多因素协同作用的承载系统,对受多向组合荷载的嵌岩双斜桩而言,存在一最优竖向设计荷载,使得嵌岩双斜桩的水平承载力大大提高,但过大的竖向荷载和过小的倾角反而提高桩承台失稳的风险。

关键词：嵌岩双斜桩桩-岩接触模型试验数值模拟承载特性

校企合作模式下基于OBE理念的实践类课程设计

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实验室研究与探索 2024年第5期43卷 182-187页

作者：胡玮尹仕陈庆叶海鹏谢荣军肖波华中科技大学电气与电子工程学院武汉430074 三峡大学电气与新能源学院湖北宜昌443002 ABB(中国)有限公司北京100020

基于成果导向教育(OBE)的课程设计理念,设计了“智慧电力工程训练营”实践课程的整体教学模式。该课程通过与ABB集团合作的形式,构建了具有实际工程意义的综合设计内容,并按照反向设计原则,对各个知识点进行综合整理,设计出2周的课程教... 详细信息

基于成果导向教育(OBE)的课程设计理念,设计了“智慧电力工程训练营”实践课程的整体教学模式。该课程通过与ABB集团合作的形式,构建了具有实际工程意义的综合设计内容,并按照反向设计原则,对各个知识点进行综合整理,设计出2周的课程教学结构和课堂教学模式,逐步实现学生的最终学习目标。在此基础上,通过教学评价体系综合评定每位学生的最终成绩。该课程的教学模式及其实施路径对于本科实践类课程设计具有较好的借鉴和推广价值。

关键词：智慧电力工程训练营实践类课程校企合作成果导向教育反向设计教学模式

LoS sensing-based superimposed CSI feedback for UAV-assisted mmWave systems

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Chinese Journal of Aeronautics 2023年第12期36卷 349-360页

作者： Chaojin qing qing ye Wenhui LIU Zilong WANG Jiafan WANG Jinliang CHEN School of Electrical Engineering and Electronic Information Xihua UniversityChengdu 610039China School of Aeronautics and Astronautics Xihua UniversityChengdu 610039China

In Unmanned Aerial Vehicle(UAV)-assisted millimeter Wave(mmWave)systems,Channel State Information(CSI)feedback is critical for the selection of modulation schemes,resource management,beamforming,***,traditional CSI feedback methods lead to significant feedback overhead and energy consumption of the UAV transmitter,therefore shortening the system operation *** tackle these issues,inspired by superimposed feedback and Integrated Sensing and Communications(ISAC),a Line of Sight(LoS)sensing-based superimposed CSI feedback scheme is ***,on the UAV transmitter side,the Ground-to-UAV(G2U)CSI is superimposed on the UAV-to-Ground(U2G)data to feed back to the ground Base Station(gBS).At the gBS,the dedicated LoS Sensing Network(LoS-SenNet)is designed to sense the U2G CSI in LoS and NLoS *** the sensed result of LoS-SenNet,the determined G2U CSI from the initial feature extraction will work as the priori information to guide the subsequent ***,for the G2U CSI in NLoS,a CSI Recovery Network(CSI-RecNet)and superimposed interference cancellation are developed to recover the G2U CSI and U2G *** for the LoS scenario,a dedicated LoS Aid Network(LoS-Aid Net)is embedded before the CSI-RecNet and the block of superimposed interference cancellation to highlight the feature of the G2U *** with other methods of superimposed CSI feedback,simulation results demonstrate that the proposed feedback scheme effectively improves the recovery accuracy of the G2U CSI and U2G ***,against parameter variations,the proposed feedback scheme presents its robustness.

关键词： Channel State Information(CSI) Integrated Sensing and Communications(ISAC) Line of Sight(LoS)sensing Superimposed CSI feedback Unmanned Aerial Vehicle(UAV)-assisted millimeter Wave(mmWave)systems

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统一框架的增强深度子空间聚类方法

计算机应用 2024年第7期44卷 1995-2003页

作者：王清赵杰煜叶绪伦王弄潇宁波大学信息科学与工程学院浙江宁波315211

深度子空间聚类是一种处理高维数据聚类任务的有效方法。然而,现有的深度子空间聚类方法通常将自表示学习和指标学习作为两个独立的过程,导致在处理具有挑战性的数据时,固定的自表示矩阵会导致次优的聚类结果;另外,自表示矩阵的质量对... 详细信息

深度子空间聚类是一种处理高维数据聚类任务的有效方法。然而,现有的深度子空间聚类方法通常将自表示学习和指标学习作为两个独立的过程,导致在处理具有挑战性的数据时,固定的自表示矩阵会导致次优的聚类结果;另外,自表示矩阵的质量对聚类结果的准确性至关重要。针对上述问题,提出一种统一框架的增强深度子空间聚类方法。首先,通过将特征学习、自表示学习和指标学习集成在一起同时优化所有参数,根据数据的特征动态地学习自表示矩阵,确保准确地捕捉数据特征;其次,为了提高自表示学习的效果,提出类原型伪标签学习,为特征学习和指标学习提供自监督信息,进而促进自表示学习;最后,为了增强嵌入表示的判别能力,引入正交性约束帮助实现自表示属性。实验结果表明,与AASSC(Adaptive Attribute and Structure Subspace Clustering network)相比,所提方法在MNIST、UMIST、COIL20数据集上的聚类准确率分别提升了1.84、0.49、0.34个百分点。可见,所提方法提高了自表示矩阵学习的准确性,聚类效果更好。

关键词：深度子空间聚类自表示学习指标学习亲和矩阵正交约束

基于SWOT-AHP湘东地区非遗与乡村旅游深度融合的路径探析

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现代农业研究 2024年第8期30卷 72-77页

作者：王清方宇杨青刘怡宏叶洋滈长沙理工大学湖南长沙410114

SWOT-AHP分析法为湘东地区非遗+乡村旅游提供了一个有效的框架,本文深入探讨了其内外部竞争环境、竞争条件、各种因素之间的协同作用,并且构建出一个完整、系统、准确的乡村旅游模式情景,最终提出了一条振兴湘东地区非遗+乡村旅游的路径... 详细信息

SWOT-AHP分析法为湘东地区非遗+乡村旅游提供了一个有效的框架,本文深入探讨了其内外部竞争环境、竞争条件、各种因素之间的协同作用,并且构建出一个完整、系统、准确的乡村旅游模式情景,最终提出了一条振兴湘东地区非遗+乡村旅游的路径:“非遗+”,即推动供给侧结构性改革,构建乡村旅游产业新体系;“产学研销”,即实施协同创新,实现乡村旅游的发展与繁荣。通过推动非遗产业化,为乡村旅游提供强有力的支撑;利用“区域协同”平台,拓展产业发展空间,打造全新的乡村旅游模式。

关键词：非遗乡村旅游 SWOT-AHP 文旅融合