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Numerical and theoretical study of load transfer behavior during cascading pillar failure

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3014-3033页

作者： Hangyu Dong Wancheng Zhu Leilei Niu chen hou Xige Liu College of Geosciences and Engineering North China University of Water Resources and Electric PowerZhengzhou450046China Center for Rock Instability and Seismicity Research School of Resource and Civil EngineeringNortheastern UniversityShenyang110819China

To further study the load transfer mechanism of roofemulti-pillarefloor system during cascading pillar failure(CPF),numerical simulation and theoretical analysis were carried out to study the three CPF modes according to the previous experimental study on treble-pillar specimens,*** failure mode(SFM),domino failure mode(DFM)and compound failure mode(CFM).Based on the finite element code rock failure process analysis(RFPA^(2D)),numerical models of treble-pillar specimen with different mechanical properties were established to reproduce and verify the experimental results of the three CPF *** results show that the elastic rebound of roofefloor system induced by pillar instability causes dynamic disturbance to adjacent pillars,resulting in sudden load increases and sudden jump displacement of adjacent *** phenomena of load transfer in the roofemulti-pillarefloor system,as well as the induced accelerated damage behavior in adjacent pillars,were discovered and *** addition,based on the catastrophe theory and the proposed mechanical model of treble-pillar specimen edisc spring group system,a potential function that characterizes the evolution characteristics of roof emulti-pillarefloor system was *** analytical expressions of sudden jump and energy release of treble-pillar specimenedisc spring group system of the three CPF modes were derived according to the potential *** numerical and theoretical results show good agreement with the experimental *** study further reveals the physical essence of load transfer during CPF of roof emulti-pillarefloor system,which provides references for mine design,construction and disaster prevention.

关键词： Cascading pillar failure(CPF) Load transfer Multi-pillar Numerical simulation

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MoO_(x) nanoclusters on Mo-doped TiO_(2) nanosheets with enhanced singlet oxygen generation and sulfide conversion abilities for photocatalytic aerobic oxidative desulfurization

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Science China Chemistry 2024年第1期67卷 408-414页

作者： Suting Xie Xinyu Zhao Dongxiao Wang Huawei Yang Lixia Yang Liangjiu Bai Donglei Wei Wenxiang Wang Ying Liang hou chen Shaojun Guo College of Chemistry and Materials Science Ludong UniversityYantai 264025China College of Materials Science and Engineering Peking UniversityBeijing 100871China

Photocatalytic aerobic oxidation desulfurization(PAODS)is a promising and sustainable alternative to conventional,energyintensive desulfurization techniques for petroleum ***,its development is greatly plagued by the low capability in generating highly reactive oxygen species and sluggish kinetics of sulfide oxidation of reported *** we report a class of MoO_(x)nanocluster decorated on ultrathin Mo-doped TiO_(2)nanosheet(MoO_(x)/MoTiO)catalyst for efficiently facilitating the photocatalytic aerobic oxidation of *** demonstrate that MoO_(x)/MoTiO can not only promote the generation of highly reactive singlet oxygen(^(1)O_(2))but also enhance the aerobic conversion of sulfides,which leads to a record dibenzothiophene oxidation activity of 3.90 mmol g^(-1)h^(-1).The multiple experimental characterizations and density functional theory calculations collectively reveal that the doped-Mo sites can interact with the photogenerated excitons,enabling directly energy transfer generation of^(1)O_(2)through a new exciton modulation mechanism,and the coordination unsaturated MoO_(x)clusters play the role of co-catalyst to enhance the separation of charge carriers,and effectively catalyze the reaction between sulfides and1O_(2)to form sulfones.

关键词： titanium dioxide photocatalytic aerobic oxidation desulfurization dibenzothiophene singlet oxygen

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Pomegranate juice combined with inulin promote their mutual metabolic transformation by gut microbiota and prevent HFD-induced metabolic disorder in rats

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Food Science and Human Wellness 2024年

作者： Xiaoyu Song Zhuoting Luo Mengting Li Jianke Li chen hou College of Food Engineering and Nutritional Science， Shaanxi Normal University University Key Laboratory of Food Processing Byproducts for Advanced Development and High Value Utilization， Shaanxi Normal University

High-fat diet (HFD) promotes the imbalance of gut microbiota， contributing to the development of metabolic disorders. Pomegranate juice (PJ) and inulin， as dietary polyphenol and dietary fiber respectively， have been reported to ameliorate diet-induced gut microbiota dysbiosis and metabolic disorders. However， the combined effect of PJ and inulin on HFD-induced metabolic disorders has not been elucidated. In current study， we found that the combination of PJ and inulin prevent HFD-induced obesity， dyslipidemia， and gut microbiota dysbiosis. Moreover， the fecal levels of short-chain fatty acids (SCFAs) produced by inulin were increased after inulin combined with PJ. The levels of pomegranate polyphenol metabolites produced by PJ were also increased after PJ combined with inulin， especially pharmacokinetic analysis showed that the presence of inulin enhance the absorption level of urolithin A. Fecal metabolomic analysis found that PJ combined with inulin alter the metabolic status compared with PJ. It was also showed that the levels of SCFAs and pomegranate polyphenol metabolites among groups were correlated with gut microbiota and metabolic disorders indicators. Our results suggested that PJ combined with inulin prevent HFD-induced metabolic disorders， which may be attributed to the promotion of mutual metabolic transformation and absorption of PJ and inulin by gut microbiota.

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Pomegranate peel polyphenols improves diet-induced obesity and promotes adipose browning development through gut microbiota in mice

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Food Science and Human Wellness 2024年

作者： Zhuoting Luo Xiaoyu Song Mengting Li Jianke Li chen hou University Key Laboratory of Food Processing Byproducts for Advanced Development and High Value Utilization， Shaanxi Normal University College of Food Engineering and Nutritional Science， Shaanxi Normal University

Gut microbiota regulate the activation of adipose browning， which promote energy dissipation and combat diet-induced obesity. Pomegranate peel polyphenols (PPPs) have been shown to reduce obesity， regulate lipid metabolism in adipose tissue， and modulate the composition of gut microbiota in animal fed high-fat diet (HFD). However， the role of gut microbiota in the improvement of obesity by PPPs has not been elucidated. In current study， we applied antibiotics to inhibit gut microbiota in mice fed HFD and treated with PPPs. The results showed that the inhibition of gut microbiota impair the effect of PPPs on reducing obesity and promoting adipose browning， and change the fecal metabolomic profiles in respond to PPPs. Moreover， the inhibition of gut microbiota supressed the promotive effects of PPPs on the levels of Akkermansia and microbiota-related metabolites， such as urolithin A， short-chain fatty acids (SCFAs)， and bile acids (BAs)， which were associated with activating adipose browning. Therefore， our results suggested that the presence of gut microbiota is essential for PPPs to ameliorate HFD-induced obesity. The related bacteria or metabolites generated by the interaction between PPPs and microbiota promote adipose browning and facilitate the beneficial effects of PPPs.

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Broadband and fabrication-tolerant 3-dB couplers with topological valley edge modes

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Light(Science & Applications) 2024年第8期13卷 1623-1630页

作者： Guo-Jing Tang Xiao-Dong chen Lu Sun Chao-Heng Guo Meng-Yu Li Zhong-Tao Tian hou-Hong chen Hong-Wei Wang Qi-Yao Sun Ying-Di Pan Xin-Tao He Yi-Kai Su Jian-Wen Dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China

3-dB couplers,which are commonly used in photonic integrated circuits for on-chip information processing,precision measurement,and quantum computing,face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication *** address this,we introduce topological physics to nanophotonics,developing a framework for topological 3-dB *** couplers exhibit broad working wavelength range and robustness against fabrication dimensional *** leveraging valley-Hall topology and mirror symmetry,the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering *** analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 20 *** further propose a topological interferometer for on-chip distance measurement,which also exhibits robustness against dimensional *** extension of topological principles to the fields of interferometers,may open up new possibilities for constructing robust wavelength division multiplexing,temperature-drift-insensitive sensing,and optical coherence tomography applications.

关键词： topological splitting insensitive

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农业知识图谱技术研究现状与展望

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农业机械学报 2024年第6期55卷 1-17页

作者：侯琛牛培宇中国农业大学信息与电气工程学院北京100083 北京大学大数据分析与应用技术国家工程实验室北京100871

在当前农业信息化的发展进程中,多数农业子领域面临着数据资源分散、信息整合难度大、知识利用效率低等问题。作为近年来新兴的一种知识表示技术,知识图谱已在部分农业特定领域展现出了强大的语义推理和数据整合能力,同时帮助一些农业... 详细信息

在当前农业信息化的发展进程中,多数农业子领域面临着数据资源分散、信息整合难度大、知识利用效率低等问题。作为近年来新兴的一种知识表示技术,知识图谱已在部分农业特定领域展现出了强大的语义推理和数据整合能力,同时帮助一些农业上层应用提高了性能。为系统总结近年来农业知识图谱构建与应用方面的研究成果,本文首先阐述了知识图谱基础和农业知识图谱的构建流程,并从本体建模、信息抽取、知识融合以及知识加工4方面总结了构建农业知识图谱所涉及的关键技术。将当前农业知识图谱的应用分为信息检索、问答系统、推荐系统、专家诊断系统和作物预测5方面,并对这些应用工作进行了梳理。最后,对当前农业知识图谱的研究现状进行了总结,并认为未来农业知识图谱可以从多模态知识推理、强时效性知识更新、多语言知识查询、跨领域数据融合以及子领域知识图谱构建等方面加以研究。

关键词：知识图谱农业领域信息检索问答系统推荐系统专家诊断系统作物预测

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Beneficial effects of lacquer seed oil on bromocriptine-induced postpartum hypogalactia in rats

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Food Science and Human Wellness 2024年

作者： Mengting Li Xiaoyu Song Lin Shi Jie Li Mayira·Ahat Yaojie Liu chen hou Jianke Li University Key Laboratory of Food Processing Byproducts for Advanced Development and High Value Utilization， Shaanxi Normal University College of Food Engineering and Nutritional Science， Shaanxi Normal University

The high incidence of postpartum hypogalactia hinders the healthy development of postpartum women and the next generation. Lacquer seed oil (LSO)， the oil extracted from the seeds of the lacquer tree， has been traditionally used as a dietary supplement for promoting postpartum lactation and recovery in some districts of China. However， its physiological effects have not been verified， and the mechanism and active components of LSO have not been analyzed. Thus， we applied LSO to bromocriptine-induced postpartum hypogalactia rats. The results showed that LSO supplement effectively improves bromocriptine-induced postpartum hypogalactia. LSO also increased prolactin levels reduced by bromocriptine， promoted JAK2/STAT5 and PI3K/AKT pathways and several gene expression levels of milk synthesis in mammary gland. Moreover， metabolomic and network pharmacological analysis further revealed that JAK2/STAT5， PI3K/AKT， and estrogen signaling pathway are the potential main regulatory sites for the beneficial effects of LSO on postpartum hypogalactia， and that quercetin， kaempferol， arachidonic acid， epicatechin， and β-sitosterol are the top 5 main active ingredients of LSO. Our results suggested that LSO has great potential in the application of the improvement of postpartum hypogalactia.

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基于文本数据增强的中文水稻育种问句命名实体识别

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农业机械学报 2024年第8期55卷 333-343页

作者：牛培宇侯琛中国农业大学信息与电气工程学院北京100083 北京大学大数据分析与应用技术国家工程实验室北京100871 北京大学长沙计算与数字经济研究院长沙410205

针对现有水稻育种问答系统存在数据管理水平低、知识粒度大,水稻育种领域缺乏用于命名实体识别的标注数据、人工标注成本高等问题,提出了一种基于文本数据增强的方法来识别水稻育种问句的命名实体,通过构建水稻育种知识图谱,对水稻育种... 详细信息

针对现有水稻育种问答系统存在数据管理水平低、知识粒度大,水稻育种领域缺乏用于命名实体识别的标注数据、人工标注成本高等问题,提出了一种基于文本数据增强的方法来识别水稻育种问句的命名实体,通过构建水稻育种知识图谱,对水稻育种问句中的大类命名实体进行分类,从而增强实体边界,降低知识粒度。针对水稻育种数据标注成本高导致命名实体识别性能不佳的难点,通过在BERT-BILSTM-CRF模型中引入数据增强层,提出了DA-BERT-BILSTM-CRF模型。实验以标注的水稻育种问句为训练数据,将所提出的模型与其他基线模型进行比较。结果表明,本文方法在水稻育种问句中命名实体识别的单类别识别任务和整体识别任务上均优于其他方法,其中单类别识别精确率达到94.26%,F1值达到93.32%;整体识别精确率达到93.86%,F1值达到93.34%。

关键词：水稻育种问答系统命名实体识别文本数据增强知识图谱

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热处理对2195铝锂合金微观组织与力学性能的影响

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塑性工程学报 2024年第6期31卷 217-225页

作者：邢宇涵蒋少松侯晨睿哈尔滨工业大学金属精密热加工国家级重点实验室黑龙江哈尔滨150001 中国航发北京航空材料研究院先进钛合金重点实验室北京100095

对T8态2195铝锂合金板材实施不同条件下的固溶处理(430、 450、 470、 490和510℃)以及时效处理(18、 24和36 h),通过室温拉伸试验对固溶和时效处理后合金的抗拉强度与伸长率进行测量,采用SEM、 XRD、 EBSD和TEM对拉伸断口及微观组织进... 详细信息

对T8态2195铝锂合金板材实施不同条件下的固溶处理(430、 450、 470、 490和510℃)以及时效处理(18、 24和36 h),通过室温拉伸试验对固溶和时效处理后合金的抗拉强度与伸长率进行测量,采用SEM、 XRD、 EBSD和TEM对拉伸断口及微观组织进行观察。结果表明:固溶处理后的应力-应变曲线存在锯齿流变现象,但时效处理后消失,推测其产生的原因是波特文-勒夏特利埃效应。固溶处理可以有效提升合金的塑性,而时效处理则提高了合金的强度。进一步分析固溶与时效过程中的微观组织变化发现, β′相不参与固溶与时效析出,时效处理后强度的增加源于θ′相和δ′相析出产生的沉淀强化及弥散强化作用。

关键词： 2195铝锂合金热处理微观组织力学性能时效析出相

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“固边圉”与“辟利源”——民国时期黑龙江省设治局设立模式探析

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地域文化研究 2024年第4期 60-69页

作者：侯晨复旦大学历史地理研究中心上海200433

设治局是民国时期中央政府为加强对地方的控制而采用的一项重要政治制度,黑龙江省地处边疆,清末至民国时期中央政府从加强对地方控制及巩固国防的角度入手,在黑龙江全省进行区划调整,在调整中着重增设政区,其中设治局数量尤多,成为这一... 详细信息

设治局是民国时期中央政府为加强对地方的控制而采用的一项重要政治制度,黑龙江省地处边疆,清末至民国时期中央政府从加强对地方控制及巩固国防的角度入手,在黑龙江全省进行区划调整,在调整中着重增设政区,其中设治局数量尤多,成为这一时期政区增设的一大特色。根据增设政区的地理分布情况,大体可以分为三种类型。即:内地型、沿边型及蒙区型。虽然设治局在设立时有一定急功近利的行为,导致部分设治局并未起到应有的作用,但总体而言黑龙江省所设立的设治局在促进地方开发、巩固国防方面都起到了明显的积极作用,极大地推动了黑龙江省政治、经济文化的发展。

关键词：历史地理学黑龙江设治局地方开发巩固国防

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