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Clustering gully profiles for investigating the spatial variation in landform formation on the Chinese Loess Plateau

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Journal of Mountain Science 2021年第10期18卷 2742-2760页

作者： CHENG Yao li jing-wei XIONG li-yang TANG Guo-an Key Laboratory of Virtual Geographic Environment(Nanjing Normal University) Ministry of EducationNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

The gully is the most dynamic and changeable landform unit on the Loess Plateau,and the characteristics of gully landforms are key indicators of gully *** gully profiles are connected and combined through runoff ***,it is necessary to cluster gully profiles into a gully profile combination(GPC)to reveal the spatial variation in gully landforms throughout the Loess ***,the gradient and gully evolution index(GEI)of two sample areas in Changwu and Suide in Shaanxi Province,China are calculated and analysed based on ***,the gradient and GEI are calculated by using 90-m-resolution digital elevation model(DEM)data for the severe soil erosion area with the basin as the research *** this basis,the spatial variation in the development degree is analysed with Getis-Ord Gi*.The results show that the degree of gully undercutting decreases from southeast to northwest under the influence of *** to the soil properties,the loess in the northwest is more prone to collapse,resulting in the decrease of GEI from northwest to *** development degree of gullies is closely related to *** strong erosive capacity of rivers leads to greater differences in gullies within the *** the same time,the skewness and kurtosis of the gully index in the basin are correlated;when the distribution of the gully index in the basin is less normal,the distribution of the gully index is more *** results reveal the spatial variation characteristics of the Loess Plateau based on GPC.

关键词： Gully profile combination Spatial variation Digital elevation model Loess landform Terrain analysis

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A New Route for Synthesis of Entecavir

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Chinese Chemical Letters 2006年第7期17卷 907-910页

作者： li wei GUO Yuan jing XIAO li Ping YANG Department of chemistry East China Normal University Shanghai 200062

A new economical synthetic route of the key intermediate 6. The synthesis of a modified Mitsunobu reaction. of entecavir was presented, involving the preparation 6 was conveniendy achieved in good overall yield by a m... 详细信息

关键词： Entecavir new route synthesis.

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肠道微生物与乳房恶性肿瘤的因果关系:双样本孟德尔随机化分析

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中国现代普通外科进展 2025年第02期28卷 108-113页

作者：梁爽连文静梁鸿艺李静蔚山东中医药大学第一临床医学院山东中医药大学附属医院乳腺甲状腺外科

目的：探讨肠道微生物与乳房恶性肿瘤之间的因果关系，并通过孟德尔随机化（MR）分析确定特定因果微生物分类群。方法：对有关肠道微生物群和乳房恶性肿瘤的全基因组关联研究（GWAS）汇总统计数据，MiBioGen研究GWAS(N=18473)作为暴露... 详细信息

目的：探讨肠道微生物与乳房恶性肿瘤之间的因果关系，并通过孟德尔随机化（MR）分析确定特定因果微生物分类群。方法：对有关肠道微生物群和乳房恶性肿瘤的全基因组关联研究（GWAS）汇总统计数据，MiBioGen研究GWAS(N=18473)作为暴露样本，IEU Open GWAS数据库中乳房恶性肿瘤的GWAS(N=123579)作为结果样本。采用逆方差加权（IVW）、加权中位数和MR-Egger方法分析MR统计结果。结果：巴斯德菌目（Pasteurellales）丰度的升高会增加乳房恶性肿瘤患病风险（IVW PFDR<0.05,OR=1.21,95%CI:1.07～1.36），水平基因多效性和异质性检测验证不会对因果关系产生影响，留一法敏感性分析表明，已确定的因果关联不是由任何单个工具变量驱动的，因果关系为正向。结论：肠道中巴斯德菌目丰度升高可能会增加乳房恶性肿瘤的发生风险。

关键词：乳腺肿瘤,恶性肠道菌群孟德尔随机化因果关系

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“夸父一号”卫星莱曼阿尔法太阳望远镜在轨平场定标偏摆方案及结果

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天文学报 2025年第1期66卷 104-120页

作者：李敬伟黎辉封莉李瑛黄宇李友平赵洁卢磊应蓓丽薛建朝葛蕴翊张萍宋得朝李巧李舒婷田俊李根刘骁锋史广禄单家辉荆志辰田正圆周玥甘为群中国科学紫金山天文台院暗物质与空间天文重点实验室南京210023 中国科学技术大学天文与空间科学学院合肥230026

获得真实的日面观测图像,是用户基于太阳望远镜开展科学和应用研究的基础,而平场定标是科学数据生产过程中的必要步骤之一,因为平场定标可以扣除太阳望远镜在成像过程中产生的不均匀性.“夸父一号”又名先进天基太阳天文台(Advanced Spa... 详细信息

获得真实的日面观测图像,是用户基于太阳望远镜开展科学和应用研究的基础,而平场定标是科学数据生产过程中的必要步骤之一,因为平场定标可以扣除太阳望远镜在成像过程中产生的不均匀性.“夸父一号”又名先进天基太阳天文台(Advanced Space-based Solar Observatory,ASO-S)卫星的载荷之一,莱曼阿尔法太阳望远镜(Lyman-alpha Solar Telescope,LST),包括3台科学仪器,具体来说是由一个双波段太阳日冕仪(Solar Corona Imager,SCI)以及白光太阳望远镜(White-light Solar Telescope,WST)和莱曼阿尔法全日面太阳成像仪(Solar Disk Imager,SDI)这两个全日面太阳望远镜构成.WST和SDI的探测器是互补金属氧化物半导体(Complementary Metal-Oxide-Semiconductor,CMOS),其平场本身的主要特征是由于激光退火造成的条纹结构,当CMOS探测器在紫外波段使用时会产生一定的衰减与辐射损伤,并且探测器上的水汽凝结和有机物的积累等污染,也会对所得平场产生一定影响.主要展示了ASO-S卫星发射两年多来,载荷LST的两个仪器WST和SDI在轨平场定标时使用的偏摆方案及其优化以及获得的平场图像和其随时间的演化情况等,并简要地介绍了WST和SDI探测器随时间的衰减和辐射损伤情况.

关键词：太阳:耀斑太阳:日冕物质抛射太阳:光球太阳:紫外辐射

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Dual Phase Heat Treatment of Low-Alloy Steel

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Journal of Iron and Steel Research International 2005年第5期12卷 47-51页

作者： HAN Jian-min CUI Shi-hai li wei-jing MA Xiao-yan Beijing Jiaotong University Beijing 100044 China

Dual phase heat treatment is an economical and effective way for improving the properties of low carbon steels and low-alloy steel materials. In this paper, the microstructures and mechanical properties of 20MnSi steel treated by different dual phase heat treatment have been studied. The results show that dual phase heat treatment with pre-quenching technique and then heating from room temperature to the critical zone can achieve finer and more homogeneous microstructure than that with pre-normalizing technique and then cooling from austenite zone to the critical zone. Among all factors affecting dual phase heat treatment, quenching temperature at the critical zone and tempering temperature play an important part in mechanical properties. Using proper dual phase heat treatment technique with computer optimized parameters, the yield strength, the elongation and impact toughness of 20MnSi can reach 860 MPa, 16% and 207 MPa respectively.

关键词： low-alloy steel dual phase heat treatment microstructure optimization

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Representation of the Arctic Oscillation in the CMIP5 Models

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Advances in Climate Change Research 2013年第4期4卷 242-249页

作者： ZUO Jin-Qing li wei-jing REN Hong-li Chinese Academy of Meteorological Sciences Laboratory for Climate Studies National Climate CenterChina Meteorological Administration

The temporal variability and spatial pattern of the Arctic Oscillation(AO)simulated in the historical experiment of26 coupled climate models participating in the Coupled Model Intercomparison Project Phase 5(CMIP5)are *** analysis of the monthly AO index indicates that 23 out of the 26 CMIP5 models exhibit no statistically significant spectral peak in the historical experiment,as seen in the *** models are able to reproduce the AO pattern in the sea level pressure anomaly field during boreal winter,but the intensity of the AO pattern tends to be overestimated in all the *** zonal-mean zonal wind anomalies associated with the AO is dominated by a meridional dipole in the mid-high latitudes of the Northern Hemisphere during boreal winter,which is well reproduced by only a few *** models show significant biases in both strength and location of the dipole compared to the *** considering the temporal variability as well as spatial structures in both horizontal and vertical directions,the MPI-ESM-P model reproduces an AO pattern that resembles the observation the best.

关键词： Arctic Oscillation model evaluation coupled climate model CMIP5

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Evaluation of Curvularia lunata Strain B6 as a Potential Mycoherbicide to Control Barnydrgrass (Echinochloa crus-galli)

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Journal of Integrative Agriculture 2013年第7期12卷 1201-1207页

作者： li jing wei Tao SUN Ai-rui NI Han-wen College of Agronomy and Biotechnology China Agricultural University

The virulent strain B6 of Curvularia lunata was screened out from 65 fungus strains isolated from the diseased leaves of barnyardgrass （Echinochloa crus-galli）. Greenhouse and field studies were conducted to evaluate the feasibility of the strain being exploited as a mycoherbicide for barnyardgrass control in paddy fields. The results of pathogenicity experiments showed that this strain was highly pathogenic to barnyardgrass at the 1- to 2.5-leaf stages. The fresh weight reduction increased with the increase of inoculated conidial concentrations and the prolongation of dew duration. Strain B6 provided excellent barnyardgrass control when it was applied at the concentration of 1×104-1×106 conidia mL-1 in paddy fields with water layer. This strain was very safe to rice and the most plant species except wheat, barley and corn. Findings of this study indicated that this strain could be a potential mycoherbicide for barnyardgrass control in paddy fields in the future.

关键词： barnyardgrass Curvularia lunata biological control mycoherbicide rice

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Phosphite ligand Modified Supported Rhodium Catalyst for Hydroformylation of Internal Olefins to linear Aldehydes

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Chemical Research in Chinese Universities 2009年第5期25卷 738-739页

作者： li Xian-ming DING Yun-jie JIAO Oui-ping li jing-wei YAN li ZHU He-jun Laboratory of Applied Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P R. China State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 P R. China Graduate School of Chinese Academy of Sciences Beijing 100049 P R. China

A phosphite ligand modified heterogeneous catalyst was developed for the hydroformylation of internal olefins to linear aldehydes, which showed a high activity and high regioselectivity and could be separated easily by filtration after reaction in an autoclave. Three nanoporous silica sieves were used to investigate the influence of pore structure and shape selective performance of support on the regioselectivity to the linear products.

关键词： Phosphite ligand Hydroformylation Internal olefin Shape selective performance

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Kinetics of Reduction Reaction in Micro-Fluidized Bed

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Journal of Iron and Steel Research International 2012年第6期19卷 6-8页

作者： liN Yin-he GUO Zhan-cheng TANG Hui-qing REN Shan li jing-wei State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Micro-fluidized bed reactor is a new research method for the reduction of iron ore fines. The reactor is op- erated as a differential reactor to ensure a constant gas concentration and temperature within the reactor volume. In order to understand the dynamic process of the reduction reaction in micro-fluidized bed, a series of kinetic experi- ments were designed. In the micro fluidized bed, the use of shrinking core model describes the dynamic behavior of reduction of iron ore. And the apparent activation energy is calculated in the range of 700--850 ~C while the initial atmosphere is 100% content of CO.

关键词： iron ore reduction micro-fluidized bed dynamics

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Domain generalization with semi-supervised learning for people-centric activity recognition

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Science China(Information Sciences) 2025年第1期68卷 171-188页

作者： jing liU wei ZHU Di li Xing HU liang SONG Academy for Engineering & Technology Fudan University Shanghai East-bund Research Institute on Networking Systems of AI School of Optoelectronic Information and Computer Engineering University of Shanghai for Science & Technology

People-centric activity recognition is one of the most critical technologies in a wide range of real-world applications,including intelligent transportation systems, healthcare services, and brain-computer interfaces. Large-scale data collection and annotation make the application of machine learning algorithms prohibitively expensive when adapting to new tasks. One way of circumventing this limitation is to train the model in a semi-supervised learning manner that utilizes a percentage of unlabeled data to reduce the labeling burden in prediction tasks. Despite their appeal, these models often assume that labeled and unlabeled data come from similar distributions, which leads to the domain shift problem caused by the presence of distribution gaps. To address these limitations, we propose herein a novel method for people-centric activity recognition,called domain generalization with semi-supervised learning(DGSSL), that effectively enhances the representation learning and domain alignment capabilities of a model. We first design a new autoregressive discriminator for adversarial training between unlabeled and labeled source domains, extracting domain-specific features to reduce the distribution gaps. Second, we introduce two reconstruction tasks to capture the task-specific features to avoid losing information related to representation learning while maintaining task-specific consistency. Finally, benefiting from the collaborative optimization of these two tasks, the model can accurately predict both the domain and category labels of the source domains for the classification task. We conduct extensive experiments on three real-world sensing datasets. The experimental results show that DGSSL surpasses the three state-of-the-art methods with better performance and generalization.

关键词： activity recognition deep learning domain generalization semi-supervised learning adversarial training

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