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耐低温复合菌剂HT20作用下秸秆还田对土壤胞外酶活性及细菌群落结构的影响
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作者 孙建平 李皓 +2 位作者 赵子婧 刘雅辉 戴相林 《山东农业科学》 北大核心 2026年第1期93-103,共11页
为探明冀东稻区耐低温复合菌剂HT20作用下秸秆还田对土壤生物性状的影响,以无秸秆还田(CK)为对照,设置未施菌剂秸秆还田(J0)和配施HT20秸秆还田(JH)两个处理,利用高通量测序技术,荧光光度法和实时荧光定量PCR法,研究不同处理对土壤胞外... 为探明冀东稻区耐低温复合菌剂HT20作用下秸秆还田对土壤生物性状的影响,以无秸秆还田(CK)为对照,设置未施菌剂秸秆还田(J0)和配施HT20秸秆还田(JH)两个处理,利用高通量测序技术,荧光光度法和实时荧光定量PCR法,研究不同处理对土壤胞外酶、纤维素分解基因和细菌群落结构及功能的影响。结果表明,与JH处理相比,CK和J0处理在部分生育期内显著抑制了土壤胞外酶活性以及纤维素分解基因cbhI和GH48的丰度(P<0.05)。具体而言,α-葡萄糖苷酶活性在移栽期分别降低19.52%和26.12%,成熟期分别降低19.79%与9.02%;β-葡萄糖苷酶活性在分蘖期分别降低23.58%与18.74%;β-木糖苷酶活性在移栽期分别降低39.70%和2.96%,分蘖期分别降低59.89%和25.09%,成熟期分别降低20.53%和25.33%;cbhI基因丰度在移栽期分别降低83.33%和44.93%,孕穗期分别降低53.28%和15.86%,乳熟期分别降低66.03%和25.80%,成熟期分别降低72.53%和41.93%;GH48基因丰度在移栽期分别降低71.83%和69.51%,分蘖期分别降低65.36%和56.28%,乳熟期分别降低68.43%和42.71%。JH处理改变了土壤细菌群落结构及表型功能特征,主要组成为放线菌门、变形菌门、厚壁菌;LEfSe分析表明,土壤中差异指示物种JH处理有4个,J0处理有2个,CK有8个;BugBase表型功能预测显示,JH处理在革兰氏阳性、生物膜形成、减少致病性和厌氧方面表现突出。研究结果从分子角度解释了HT20在水田中加速秸秆腐解的原因,可为优化创制新型低温腐熟剂提供理论指导。 展开更多
关键词 耐低温复合菌剂ht20 秸秆还田 土壤胞外酶 纤维素分解基因 微生物功能
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草假单胞菌HT1发酵液的促生效应及发酵条件优化
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作者 张慧 卢文才 +2 位作者 陈星如 王冬 马连杰 《中国土壤与肥料》 北大核心 2026年第1期221-228,共8页
对草假单胞菌HT1的促生抑菌特性及培养条件优化展开探究,并分析其对蚕豆的促生效应。通过测定吸光度与菌落形成单位标准曲线,发现二者线性相关显著(相关系数0.995,回归方程y=1×10^(9)x+2×10^(7))。该菌株产吲哚-3-乙酸量达109... 对草假单胞菌HT1的促生抑菌特性及培养条件优化展开探究,并分析其对蚕豆的促生效应。通过测定吸光度与菌落形成单位标准曲线,发现二者线性相关显著(相关系数0.995,回归方程y=1×10^(9)x+2×10^(7))。该菌株产吲哚-3-乙酸量达109 mg/L,产铁载体、溶磷及蛋白酶的晕圈与菌落直径比值分别为1.24、1.61和2.28,无解钾能力;对拟蚕豆葡萄孢等病原菌的抑菌圈直径在0.80~3.80 cm,其中对拟蚕豆葡萄孢抑制效果最强。经单因素和响应面试验优化,确定最佳培养条件为摇培温度31℃、初始pH 7.67、接种量1.99%,此时实测菌落数为2.55×10^(8)CFU/mL。蚕豆促生试验显示,菌液浓度5×10^(6)CFU/g时促生效果最优,株高、根长、叶面积和地上部鲜重较对照(株高12.30 cm、根长12.40 cm、叶面积7.13 cm2、地上部鲜重3.74 g)分别增加113%、29%、73.8%和56.1%。研究表明,草假单胞菌HT1在农业生物防治与作物促生方面具有良好的应用潜力。 展开更多
关键词 草假单胞菌ht1 促生特性 抑菌活性 生长条件优化 蚕豆促生效应
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灵芝孢子粉含药血清通过Nrf2/HO-1通路减轻OGD/R致HT22细胞的氧化应激损伤
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作者 黄力 李月侠 +1 位作者 马凯 金传山 《安徽中医药大学学报》 2026年第1期64-70,共7页
目的 研究灵芝孢子粉含药血清(serum containing bioactive components of Ganodermae Spora,S-GS)对氧糖剥夺/复氧(oxygen-glucose deprivation/reoxygenation,OGD/R)致小鼠海马神经元HT22细胞损伤的保护机制。方法 采用OGD/R法诱导HT2... 目的 研究灵芝孢子粉含药血清(serum containing bioactive components of Ganodermae Spora,S-GS)对氧糖剥夺/复氧(oxygen-glucose deprivation/reoxygenation,OGD/R)致小鼠海马神经元HT22细胞损伤的保护机制。方法 采用OGD/R法诱导HT22细胞损伤,加入不同浓度S-GS后,采用CCK-8法检测各组HT22细胞存活率及筛选最佳S-GS浓度,ELISA法测定各组细胞超氧化物歧化酶(superoxide dismutase,SOD)活性和乳酸脱氢酶(lactate dehydrogenase,LDH)、丙二醛(malondialdehyde,MDA)水平,AV-PI流式细胞仪测定HT22细胞凋亡率,Western blot法测定核内核因子E2相关因子2(nucleus nuclear factor E2related factor 2,N-Nrf2)、血红素加氧酶-1(heme oxygenase,HO-1)、Kelch样环氧氯丙烷相关蛋白1(Kelch-like ECH-associated protein 1,Keap1)、胞浆核因子E2相关因子2(cytoplasm nuclear factor E2related factor 2,C-Nrf2)蛋白表达水平,免疫荧光染色法测定活性氧(reactive oxygen species,ROS)水平及Nrf2核转移情况。结果 S-GS可显著升高HT22细胞中SOD活性,降低MDA、ROS水平及细胞凋亡率;且S-GS可显著升高HO-1、N-Nrf2蛋白表达水平,降低C-Nrf2、Keap1蛋白表达水平并促进Nrf2核转移。10%S-GS+ML385(Nrf2抑制剂)可显著升高细胞凋亡率及Keap1、C-Nrf2蛋白表达水平,降低HO-1、N-Nrf2蛋白表达水平及N-Nrf2荧光强度。结论S-GS可通过激活Nrf2/HO-1信号通路保护OGD/R诱导的HT22细胞免于氧化应激损伤,灵芝孢子粉可作为改善缺血性脑卒中的潜在药物。 展开更多
关键词 灵芝孢子粉含药血清 氧糖剥夺/复氧 ht22细胞 Nrf2/HO-1信号通路
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快堆UO_(2)燃料与HT9包壳化学相互作用数值模拟研究
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作者 陈楠 贺亚男 +4 位作者 章静 巫英伟 周毅 田文喜 秋穗正 《原子能科学技术》 北大核心 2026年第1期195-204,共10页
本文旨在建立一种分析UO_(2)燃料与HT9铁马体不锈钢包壳化学相互作用(FCCI)的方法,为快堆燃料的服役性能分析提供工具。基于燃料性能分析程序MOOSE-BEEs,植入了FCCI行为模型、损伤模型和隔离层模型,针对DFR、BN600实验数据以及其他经验... 本文旨在建立一种分析UO_(2)燃料与HT9铁马体不锈钢包壳化学相互作用(FCCI)的方法,为快堆燃料的服役性能分析提供工具。基于燃料性能分析程序MOOSE-BEEs,植入了FCCI行为模型、损伤模型和隔离层模型,针对DFR、BN600实验数据以及其他经验关系式进行了对比验证。采用MFF3实验工况进行腐蚀深度计算,分析了温度、接触应力和隔离层的存在对腐蚀深度的影响。计算结果显示,模型预测的腐蚀深度与实验数据和其他经验关系式相吻合,证实了模型的有效性。分析结果表明,温度和燃耗的增加促进了腐蚀反应,而芯块-包壳接触应力的存在显著加剧了腐蚀程度,导致包壳变薄,从而降低了该处承受的应力,改变了轴向应力分布。隔离层显著降低了腐蚀深度,腐蚀引起的包壳损伤可能导致包壳与芯体之间的接触松弛,从而使得接触应力随渗氮时间的增加而增大。本文模型能较准确预测包壳腐蚀深度,为快堆燃料设计和性能分析提供参考。 展开更多
关键词 UO_(2)燃料 ht9包壳 燃料包壳化学相互作用(FCCI) BEES
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不同产地牛舌草对皮质酮诱导HT-22细胞损伤的神经保护作用
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作者 丑凌芸 崔琴丹 +3 位作者 李竣 陶浩 黄先菊 张曌 《中南民族大学学报(自然科学版)》 2026年第2期168-173,共6页
以传统药用植物意大利牛舌草(Anchusa italica Retz.)的临床功效和现代药理学研究为基础,通过构建体外抑郁症模型,系统研究牛舌草的药理作用及物质基础.HPLC检测不同产地(新疆、巴基斯坦、海南)牛舌草总黄酮(TFAI)的化学成分;然后用海... 以传统药用植物意大利牛舌草(Anchusa italica Retz.)的临床功效和现代药理学研究为基础,通过构建体外抑郁症模型,系统研究牛舌草的药理作用及物质基础.HPLC检测不同产地(新疆、巴基斯坦、海南)牛舌草总黄酮(TFAI)的化学成分;然后用海马细胞(HT-22)通过皮质酮诱导建立神经细胞损伤模型,MTT法检测了5种牛舌草对HT-22细胞活力的影响,并计算其EC_(50).结果表明不同产地TFAI在500µg/mL浓度下对HT-22细胞均未表现出明显的细胞毒性作用,且对HT-22细胞具有显著的增殖作用,对过量皮质酮诱导的海马细胞损伤具有明显的细胞保护作用,比较5批牛舌草中的总黄酮含量和EC_(50)值,海南产地的牛舌草中的黄酮类含量最高,且对HT-22细胞的增殖作用EC_(50)值最低,具有较高的效价.研究结果说明五批TFAI提取物对皮质酮诱导的HT-22海马细胞损伤均具有保护作用,可以不同程度地增加HT-22细胞活力,具有显著的神经保护作用. 展开更多
关键词 意大利牛舌草 抑郁症 ht-22细胞 神经保护
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基于有限元法的HT-9钢夏比冲击上平台能量尺寸效应研究
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作者 管浩扬 王瀚霄 +2 位作者 孙璐 龚翱翔 佟振峰 《原子能科学技术》 北大核心 2026年第2期387-396,共10页
针对不同尺寸夏比冲击实验数据因存在尺寸效应而不能直接比较的现状,基于铁素体/马氏体钢HT-9单轴拉伸实验与有限元逆运算构建了Johnson-Cook(J-C)本构模型和失效模型,并标定了模型参数。开展了标准尺寸试样和KLST小尺寸夏比-V型缺口试... 针对不同尺寸夏比冲击实验数据因存在尺寸效应而不能直接比较的现状,基于铁素体/马氏体钢HT-9单轴拉伸实验与有限元逆运算构建了Johnson-Cook(J-C)本构模型和失效模型,并标定了模型参数。开展了标准尺寸试样和KLST小尺寸夏比-V型缺口试样的断裂性能测试,采用双曲正切函数拟合韧脆转变曲线,分析尺寸改变对材料断裂性能的影响。结果发现:韧脆转变温度(DBTT)随试样尺寸的减小而下降,材料的抗冲击能力随着尺寸的减小而加强。采用模拟方法研究尺寸变化对夏比-V型缺口试样的三维约束和上平台能量(USE)的影响,并建立了不同尺寸冲击试样的USE和DBTT归一化模型,预测值与实验值的相对偏差在5%以内,表明基于有限元数值模拟研究夏比冲击尺寸效应具有准确、高效的优势。 展开更多
关键词 铁素体/马氏体钢ht-9 夏比冲击实验 尺寸效应 Jonhnson-Cook模型
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A Hybrid Approach to Software Testing Efficiency:Stacked Ensembles and Deep Q-Learning for Test Case Prioritization and Ranking
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作者 Anis Zarrad Thomas Armstrong Jaber Jemai 《Computers, Materials & Continua》 2026年第3期1726-1746,共21页
Test case prioritization and ranking play a crucial role in software testing by improving fault detection efficiency and ensuring software reliability.While prioritization selects the most relevant test cases for opti... Test case prioritization and ranking play a crucial role in software testing by improving fault detection efficiency and ensuring software reliability.While prioritization selects the most relevant test cases for optimal coverage,ranking further refines their execution order to detect critical faults earlier.This study investigates machine learning techniques to enhance both prioritization and ranking,contributing to more effective and efficient testing processes.We first employ advanced feature engineering alongside ensemble models,including Gradient Boosted,Support Vector Machines,Random Forests,and Naive Bayes classifiers to optimize test case prioritization,achieving an accuracy score of 0.98847 and significantly improving the Average Percentage of Fault Detection(APFD).Subsequently,we introduce a deep Q-learning framework combined with a Genetic Algorithm(GA)to refine test case ranking within priority levels.This approach achieves a rank accuracy of 0.9172,demonstrating robust performance despite the increasing computational demands of specialized variation operators.Our findings highlight the effectiveness of stacked ensemble learning and reinforcement learning in optimizing test case prioritization and ranking.This integrated approach improves testing efficiency,reduces late-stage defects,and improves overall software stability.The study provides valuable information for AI-driven testing frameworks,paving the way for more intelligent and adaptive software quality assurance methodologies. 展开更多
关键词 Software testing test case prioritization test case ranking machine learning reinforcement learning deep Q-learning
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Driving innovation in technical textiles,digitalisation and testing
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《China Textile》 2026年第1期38-39,共2页
Members of the British Textile Machinery Association(BTMA)can look back on 2025 as a year marked by notable technological advances and continued progress in global trade,despite an uncertain and volatile market.“Our ... Members of the British Textile Machinery Association(BTMA)can look back on 2025 as a year marked by notable technological advances and continued progress in global trade,despite an uncertain and volatile market.“Our members have been very active over the past 12 months and this has resulted in new technologies for the production of technical fibres and fabrics,the introduction of AI and machine learning into process control systems and significant advances in materials testing,”says BTMA CEO Jason Kent.“There’s real excitement about what can be achieved in 2026 as we look ahead to upcoming exhibitions such as JEC Composites in Paris in March and Techtextil in Frankfurt in April.” 展开更多
关键词 technical textiles digitalisation production technical fibres technological advances process control systems materials testing says machine learning testing
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基于5-HT2AR/BDNF/MAPK/ERK信号通路的颏舌肌调控机制与阻塞性睡眠呼吸暂停治疗探索
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作者 王祥 张爱华 +3 位作者 段凌志 杨正富 王燕 李昕劼 《中医药临床杂志》 2026年第2期254-261,共8页
随着睡眠医学的发展,阻塞性睡眠呼吸暂停(OSA)的检出率逐年升高,且临床合并症多,严重影响患者的生活质量及身心健康,亟需引起社会关注。研究发现,OSA的发生与颏舌肌功能状态密切相关。颏舌肌作为上呼吸道肌群中的重要组成部分,其正常活... 随着睡眠医学的发展,阻塞性睡眠呼吸暂停(OSA)的检出率逐年升高,且临床合并症多,严重影响患者的生活质量及身心健康,亟需引起社会关注。研究发现,OSA的发生与颏舌肌功能状态密切相关。颏舌肌作为上呼吸道肌群中的重要组成部分,其正常活动有利于保持呼吸道通畅,从而防止上气道阻塞。5-HT2AR/BDNF/MAPK/ERK通路是调节颏舌肌活性的一条重要通路,在OSA的发病机制及临床治疗中占有重要地位。该文着重阐述5-HT2AR/BDNF/MAPK/ERK信号通路调控颏舌肌的具体作用机制及中医药调节该通路治疗OSA的研究现状,旨在为该病的科研及中医药防治提供思路依据。 展开更多
关键词 阻塞性睡眠呼吸暂停综合征 5-ht 5-ht2AR 颏舌肌 中医药 BDNF MAPK/ERK
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Experimental study on stress-permeability evolution of rocks under complex mining-induced loading:Insights into water inrush risk in floor strata
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作者 Jinghua Li Guichen Li +4 位作者 Lei Zhang Kaijun Miao Xiaofang Wo Yingqi Yuan Zhongwei Chen 《International Journal of Mining Science and Technology》 2026年第2期333-351,共19页
Water inrush hazards from the floor strata of longwall workingface are commonly encountered in North China coalfields,which essentially result from the evolution of permeability in the floor rock under complex mining-... Water inrush hazards from the floor strata of longwall workingface are commonly encountered in North China coalfields,which essentially result from the evolution of permeability in the floor rock under complex mining-induced stress conditions.Current research rarely addresses the evolution of rock permeability under such complex stress paths.Describing this evolution using only one stress parameter,such as effective stress,deviatoric stress,axial stress,or confining stress,is highly challenging.In this study,we developed a laboratory loading scheme that simulates mining-induced stress evolution.Hydro-mechanical experiments were conducted to investigate the evolution of rock permeability under mining stress.The mechanism on the change of stress-permeability relationships in mining-disturbed rock is revealed,supporting to the analysis of management strategies for floor water-inrush disasters.The results show that rock permeability evolves through four stages,including rapid decline,gradual fluctuation,sharp increase,and slow attenuation.1–2 permeability surges occurred during mining-stress loading,closely linked to the emergence and reversal of deviatoric stress in magnitude and direction.With the first permeability surge,the deviatoric stress within the mudstone reached approximately 1.7 MPa,whereas that of the sandstone was about 1 MPa.The second permeability surge in the mudstone corresponded to the secondary rotation of the principal stress direction.CT and ultrasonic tests suggested an increase in microcracks in both rocks during the first permeability surge.However,the deviatoric stress-permeability plot before and after mining indicated that the fracture of mudstone sample changed significantly,while that of the sandstone remained unchanged.The permeability surges observed at different stages are interpreted as resulting from shear-induced reopening of pre-existing fractures and the formation of new shear-failure fractures.A stress-permeability model jointly governed by effective mean stress and deviatoric stress was established.Furthermore,two strategies are proposed for the floor water-inrush disasters prevention,(i)timely backfilling to reduce deviatoric stress,(ii)grouting after the first permeability surge.This work provides insights into stress-seepage behavior in rocks under complex stress evolution and offers new perspectives for identifying potential water inrush pathways in the floor strata of coal seam during longwall mining. 展开更多
关键词 STRESS PERMEABILITY Mining-disturbed Hydro-mechanical tests Workingface floor
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A REST API Fuzz Testing Framework Based on GUI Interaction and Specification Completion
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作者 Zonglin Li Xu Zhao +2 位作者 Yan Cao Yazhe Li Yihong Zhang 《Computers, Materials & Continua》 2026年第3期2201-2222,共22页
With the rapid development of Internet technology,REST APIs(Representational State Transfer Application Programming Interfaces)have become the primary communication standard in modern microservice architectures,raisin... With the rapid development of Internet technology,REST APIs(Representational State Transfer Application Programming Interfaces)have become the primary communication standard in modern microservice architectures,raising increasing concerns about their security.Existing fuzz testing methods include random or dictionary-based input generation,which often fail to ensure both syntactic and semantic correctness,and OpenAPIbased approaches,which offer better accuracy but typically lack detailed descriptions of endpoints,parameters,or data formats.To address these issues,this paper proposes the APIDocX fuzz testing framework.It introduces a crawler tailored for dynamic web pages that automatically simulates user interactions to trigger APIs,capturing and extracting parameter information from communication packets.A multi-endpoint parameter adaptation method based on improved Jaccard similarity is then used to generalize these parameters to other potential API endpoints,filling in gaps in OpenAPI specifications.Experimental results demonstrate that the extracted parameters can be generalized with 79.61%accuracy.Fuzz testing using the enriched OpenAPI documents leads to improvements in test coverage,the number of valid test cases generated,and fault detection capabilities.This approach offers an effective enhancement to automated REST API security testing. 展开更多
关键词 REST APIs fuzz testing OpenAPI specifications
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HT振动输送机振动异常预警系统的研究与应用
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作者 郭硕达 崔庆育 +1 位作者 马骁飞 张兵 《设备管理与维修》 2026年第2期103-107,共5页
为监控HT振动输送机的运行情况,防止其内部烟丝聚集,导致产生湿团烟丝,通过采集多维度振动数据并将数据传入中控服务器,然后结合WTCSP算法提取数据特征,利用分类器与设备正常运行时的特征值进行比较,不仅能及时发现振动异常并报警,还可... 为监控HT振动输送机的运行情况,防止其内部烟丝聚集,导致产生湿团烟丝,通过采集多维度振动数据并将数据传入中控服务器,然后结合WTCSP算法提取数据特征,利用分类器与设备正常运行时的特征值进行比较,不仅能及时发现振动异常并报警,还可以对设备维修效果进行定量分析及精确指导,保证烘丝机出口水分的稳定性。 展开更多
关键词 ht振槽 离散小波变换 共同空间模式 振动异常报警
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Deformation characteristics of unsaturated slope during post-rainfall earthquake:Insights from centrifuge and numerical modeling
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作者 Jiawei Xu Kun Fang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期380-397,共18页
Slopes are likely to fail in areas with frequent rainfall and earthquakes.The deformation characteristics of unsaturated slopes subjected to post-rainfall earthquakes are investigated using centrifuge model tests and ... Slopes are likely to fail in areas with frequent rainfall and earthquakes.The deformation characteristics of unsaturated slopes subjected to post-rainfall earthquakes are investigated using centrifuge model tests and finite element analyses.Three tests of the slope deformation under earthquake and post-rainfall earthquakes are first studied using image analysis techniques.Then,based on an elastoplastic constitutive model,numerical simulations are carried out using the finite element method and compared with the centrifuge test results.Finally,a parametric study is performed to clarify the effects of antecedent rainfall on earthquake-induced slope deformation.The results show that slope deformation caused by post-rainfall earthquakes differs from that caused by earthquakes without antecedent rainfall.The seepage flow and soil strength of the slope are affected by previous rainfall conditions,such as intensity and duration,which directly influence the slope deformation caused by the subsequent earthquake.Soil displacement and strain become greater and the slip surface is more noticeable during the post-rainfall earthquake of higher intensity.In addition,the time interval between the rainfall and the earthquake has a considerable impact on the detailed characteristics of the slope deformation,and the significant deformation occurs at the time of lowest soil strength when seepage flow reaches the lower part of the slope.Moreover,the repeated intermittent rainfall greatly affects the subsequent earthquake-induced slope deformation,the main characteristics of which are closely related to the changes in saturation and strength of the slope.However,with the prolonged time gap between each round of rainfall,the earthquake-induced slope deformation becomes insignificant. 展开更多
关键词 SLOPE Deformation Post-rainfall earthquake Centrifuge model test Finite element analysis
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基于HT32F52352主控芯片设计的智能跟随购物车
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作者 蔡运富 王洋 +1 位作者 朱俊雪 陈乐意 《鞋类工艺与设计》 2026年第3期145-147,共3页
在人工智能与物联网赋能零售的背景下,智能购物车是行业升级的重要方向。本设计以HT32F52352为主控,整合多传感器感知、UWB室内定位及PID控制算法,构建智能移动系统,实现障碍物检测、避障、声光报警、广告投放及稳定跟随等功能。该设计... 在人工智能与物联网赋能零售的背景下,智能购物车是行业升级的重要方向。本设计以HT32F52352为主控,整合多传感器感知、UWB室内定位及PID控制算法,构建智能移动系统,实现障碍物检测、避障、声光报警、广告投放及稳定跟随等功能。该设计突破传统局限,推动移动机器人技术民用化,为智慧零售提供人机协同方案。 展开更多
关键词 智能跟随购物车 ht32F52352 自主跟随 动态避障 UWB定位
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Monotonic triaxial testing and hypoplastic modelling of calcareous sand:A focus on particle breakage and initial relative density
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作者 Jiarui Chen Yaolan Tang +4 位作者 Shun Wang Chunshun Zhang Wei Wei Jie Dong Congying Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1504-1525,共22页
The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we condu... The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we conducted a series of triaxial tests on calcareous sand with varying Dri and stress paths,examining particle breakage and critical state behavior.Key findingsinclude:(1)At a constant stress ratio(η),B follows a hyperbolic relationship with mean effective stress(p'),and for a given p',B increases proportionally withη;(2)The critical state line(CSL)moves downward with increasing Dri,whereas the critical state friction angle(φcs)decreases with increasing B.Based on these findings,we propose a unifiedbreakage evolution model to quantify particle breakage in calcareous sand under various loading conditions.Integrating this model with the Normal Consolidation Line(NCL)and CSL equations,we successfully simulate the steepening of NCL and CSL slopes as B increases with the onset of particle breakage.Furthermore,we quantitatively evaluate the effect of B onφcs.Finally,within the framework of Critical State Soil Mechanics and Hypoplasticity theory,we develop a hypoplastic model incorporating B and Dri.The model is validated through strong agreement with experimental results across various initial relative densities,stress paths and drainage conditions. 展开更多
关键词 Calcareous sand Constitutive model HYPOPLASTICITY Particle breakage Initial relative density Triaxial test
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Design and optimization of a compact high-energy electron source applied to on-site non-destructive testing for electrical equipment
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作者 Hai-Meng Wang Yi-Feng Zeng +2 位作者 Hao Hu Jun-Yang Li Tong-Ning Hu 《Nuclear Science and Techniques》 2026年第4期28-40,共13页
X-rays are widely used in the non-destructive testing(NDT)of electrical equipment.Radio frequency(RF)electron linear accelerators can generate MeV high-energy X-rays with strong penetrating ability;however,the system ... X-rays are widely used in the non-destructive testing(NDT)of electrical equipment.Radio frequency(RF)electron linear accelerators can generate MeV high-energy X-rays with strong penetrating ability;however,the system generally has a large scale,which is not suitable for on-site testing.Compared with the S-band(S-linac)at the same stage of beam energy,the accelerator working in the X-band(X-linac)can compress the facility scale by over 2/3 in the longitudinal direction,which is convenient for the on-site NDT of electrical equipment.To address the beam quality and design complexity simultaneously,the non-dominated sorting genetic algorithmⅡ(NSGA-Ⅱ),which is a multi-objective genetic algorithm(MOGA),was developed to optimize the cavity chain design of the X-linac.Additionally,the designs of the focusing coils,electron gun,and RF couplers,which are other key components of the X-linac,were introduced in this context.In particular,the focusing coil distributions were optimized using a genetic algorithm.Furthermore,after designing such key components,PARMELA software was adopted to perform beam dynamics calculations with the optimized accelerating fields and magnetic fields.The results show that the beam performance was obtained with a capture ratio of more than 90%,an energy spread of less than 10%,and an average energy of approximately 3 MeV.The design and simulation results indicate that the proposed NSGAⅡ-based approach is feasible for X-linac accelerator design.Furthermore,it can be generalized as a universal technique for industrial electron linear accelerators provided that specific optimization objectives and constraints are set according to different application scenarios and requirements. 展开更多
关键词 Non-destructive testing X-band linac accelerator Focusing coils Electron gun Radio frequency couplers
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Aptamer&MOF-functionalized multichannel paper chip for point-of-care testing of small extracellular vesicle membrane protein profile
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作者 Shaoqiang Wen Lang Zhang +7 位作者 Zhan Huang Meng Chen Yuzhi Xu Xing Huang Zhou Zhang Xiaoyong Zou Zong Dai Si-Yang Liu 《Chinese Chemical Letters》 2026年第2期687-692,共6页
Small extracellular vesicles(sEVs)membrane protein profile(sEVpp)is a novel biomarker for cancer,and it can reveal the in-depth phenotype information.The point-of-care testing(POCT)of sEVpp holds great significance fo... Small extracellular vesicles(sEVs)membrane protein profile(sEVpp)is a novel biomarker for cancer,and it can reveal the in-depth phenotype information.The point-of-care testing(POCT)of sEVpp holds great significance for mass screening of cancer,so the cost-effective and simple detection methods of sEVpp are urgently demanded.Herein,we constructed a paper-based multichannel sEVpp POCT device(sEVpp-PAD)enabled by functional DNA probes and metal-organic framework(MOF).The core components are aptamer/MOF-modified paper chips.The modified aptamers can immunocapture the sEV expressing corresponding proteins,while the modified MOF can provide abundant sites for aptamer-modification,reduce the nonspecific protein absorption,and act as reference for ratiometric detection.Simply powered by two syringes,the sEVpp-PAD can efficiently capture sEVs expressing corresponding protein from cell culture media and sera.Furthermore,a detection probe(DP)consisted of CD63 aptamer and G-quadruplex was developed for the colorimetric detection of captured sEVs.Utilizing this device,the sEVpp in various hepatocellular carcinoma cell culture medium and,more importantly,in human sera can be accurately determined,only with$2 device,$0.2 detection reagents and 1.8 h procedure.This simple strategy for sEVpp detection can innovatively promote the POCT and subtyping of cancer based on sEV-related liquid biopsy. 展开更多
关键词 Small extracellular vesicles Protein profile Point-of-care testing Paper-based analytical device Metal-organic frameworks
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Magnetic pulse welding of Al-5754 with Al-7075 and MARS 380:Weldability windows and ballistic testing
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作者 Benoit Lagain Thomas Heuzé +1 位作者 Guillaume Racineux Michel Arrigoni 《Defence Technology(防务技术)》 2026年第1期64-79,共16页
Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining... Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining technique that overcomes these issues by using impact to create strong bonds without melting the substrate materials.This study investigates the weldability of aluminum alloy Al-5754 with Al-7075 and MARS 380 steel,used in armouring solutions of defense systems,by the use of MPW.In this work,weldability windows are investigated by varying standoff distances between the coating material and its substrate(0.25-4.5 mm)and discharge energies(5-13 kJ)with both O-shape and U-shape inductors.Mechanical strength of the welded joints were assessed through single lap shear tests,identifying optimal welding parameters.Then,the velocity profiles of the flyer plates were measured using heterodyne velocimetry to understand the dynamics of the impact.Then,substructures assembled with the optimal welding conditions were subjected to ballistic testing using 7.62 mm×51 mm NATO and 9 mm×19 mm Parabellum munitions to evaluate the resilience of the welds under ballistic impact.The outcomes demonstrate that MPW effectively joins Al-5754 with both Al-7075 and MARS 380,producing robust welds capable of withstanding ballistic impacts under certain conditions.This research advances the application of MPW in lightweight ballistic protection of defense systems,contributing to the development of more resilient and lighter protective structures. 展开更多
关键词 Magnetic pulse welding(MPW) Dissimilar material joining Weldability windows Impact welding Ballistic testing
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Fracture-pore networks and brittle with ductile stress-strain mechanisms:Triaxial tests on>7,600 m samples yield insights for 10,000-m deep sandstones
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作者 Guoqi WEI Zhe ZHAO +7 位作者 Ronghu ZHANG Kaixun ZHANG Stephen ELAUBACH Chengzao JIA Qinglu ZENG Chaofeng YU Jin LAI Xiaofei XIN 《Science China Earth Sciences》 2026年第2期702-720,共19页
Basins in western China produce hydrocarbons from 8,000 m deep and have been penetrated to 10,000 m,but the mechanical and petrophysical properties of deep and ultra-deep rocks are unclear and the origins of porosity ... Basins in western China produce hydrocarbons from 8,000 m deep and have been penetrated to 10,000 m,but the mechanical and petrophysical properties of deep and ultra-deep rocks are unclear and the origins of porosity and permeability remain a mystery.Our research used core samples from a depth of 7,600 m and mechanical tests to document the likely structural and porosity evolution of sandstone due to burial to 10,000 m.During triaxial tests,we characterized microstructure evolution using micro-CT scanning images and acoustic emissions and monitored stress and strain characteristics in high-temperature and high-pressure fluid environments.Under ultra deep-burial conditions,our samples deformed by pore collapse and pore distortion and brittle and ductile fracture,independently or concurrently.Under increasing triaxial stress,temperature and fluid pressure,sandstones initially lose porosity and permeability by pore collapse and compaction then develop a network of interconnected pores and fractures.Consequently,porosity can reach 8% to 18%,possibly accounting for fluid storage and flow capacity at depths of 10,000 m.Samples from 7,600 m lack substantial quartz,calcite cement and rapid burial for our samples and rocks at 10,000 m and quartz,calcite accumulation systematics suggests that though subject to temperatures of as much as 200°C,porosity loss and gain in sandstones at 10,000 m may be primarily due to compaction.Our tests show that due to pore collapse and grain fracture,sandstones having high initial porosity and permeability have a greater increase of porosity and permeability due to loading. 展开更多
关键词 Brittle-ductile deformation Fracture-pore networks Sandstone Stress and strain Triaxial tests Ultra-deep reservoirs(>7.6 km)
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玉米大斑病菌bZIP基因家族鉴定及HT-毒素诱导过程中的表达 被引量:1
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作者 张淑红 张运峰 +5 位作者 高凤菊 武秋颖 李亚子 许可 范永山 刘玉卫 《微生物学报》 北大核心 2025年第1期283-302,共20页
【目的】碱性亮氨酸拉链(basicleucinezipper,bZIP)蛋白是真核生物中最大且最保守的转录因子之一,参与许多植物病原真菌的生长发育和致病过程。本文旨在对玉米大斑病菌(Setosphaeria turcica)bZIP转录因子进行全基因组鉴定,并探讨它们在... 【目的】碱性亮氨酸拉链(basicleucinezipper,bZIP)蛋白是真核生物中最大且最保守的转录因子之一,参与许多植物病原真菌的生长发育和致病过程。本文旨在对玉米大斑病菌(Setosphaeria turcica)bZIP转录因子进行全基因组鉴定,并探讨它们在HT-毒素诱导过程中的表达规律。【方法】从玉米大斑病菌基因组数据库中筛选鉴定bZIP家族成员,分析其理化性质、保守结构域、亚细胞定位、顺式作用元件、系统进化关系和蛋白质互作网络,利用RNA-seq数据库分析bZIP家族成员在HT-毒素诱导过程中的表达情况。【结果】从玉米大斑病菌基因组筛选到14个bZIP家族成员(StbZIP1-14),其理化性质差异较大,编码氨基酸226-613个,相对分子量25.24-66.30 kDa,等电点4.66-10.36;亚细胞定位均为细胞核,含有非生物因素胁迫、激素诱导、细胞周期调控和增强子、核心启动子等660个顺式作用响应元件。与11个其他重要植物病原真菌的系统进化分析结果表明,StbZIPs可分为10个类群(groups),与互隔交链孢霉(Alternaria alternata)的AabZIPs存在明显的共线性关系。分析StbZIPs在HT-毒素诱导过程中的表达情况,发现StbZIP1、StbZIP5、StbZIP7、StbZIP10、StbZIP11与HT-毒素诱导显著相关,其中StbZIP5表达量最高并在HT-毒素诱导21 d和28 d时显著上调。分析了StbZIPs的蛋白质互作网络,提供了3条以StbZIP5为中心的StbZIPs互作途径。【结论】玉米大斑病菌bZIP转录因子家族成员具有显著的理化性质和结构差异、广泛的遗传多样性和显著的功能分化,并在HT-毒素诱导过程中发挥重要的转录调控作用。 展开更多
关键词 玉米大斑病菌 碱性亮氨酸拉链蛋白 系统进化分析 ht-毒素 表达分析
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