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三向斜锚短桩基础拉拔荷载作用下桩锚节点的受力特性分析

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岩土力学 2025年第1期46卷 278-288页

作者：田雷谢强段军陶富涛班宇鑫傅翔晏彬淇国网经济技术研究院有限公司北京102209 重庆大学土木工程学院重庆400045 库区环境地质灾害防治国家地方联合工程研究中心(重庆) 重庆400045 重庆大学山地城镇建设与新技术教育部重点实验室重庆400045 重庆科技大学土木与水利工程学院重庆401331 重庆交通大学河海学院重庆400074

针对输电线路中山区上覆土层、下卧岩层的地层条件,为增加桩基础抗拉拔性能,提出了一种锚固板钢筋锚固形式的斜锚短桩基础,开展了钢筋混凝土短桩-3向斜锚杆基础节点室内模型试验,研究了拉拔荷载作用下桩锚节点的受力特性与破坏机制。结... 详细信息

针对输电线路中山区上覆土层、下卧岩层的地层条件,为增加桩基础抗拉拔性能,提出了一种锚固板钢筋锚固形式的斜锚短桩基础,开展了钢筋混凝土短桩-3向斜锚杆基础节点室内模型试验,研究了拉拔荷载作用下桩锚节点的受力特性与破坏机制。结果表明:短桩与锚筋协同工作,最先于锚杆节点处产生拉裂缝,进而形成竖向主裂缝不断向桩顶延伸,致使试件整体劈裂破坏。试件的开裂荷载约为150 kN、屈服荷载约为1611 kN、极限荷载约为1845 kN,破坏前锚筋全部屈服,桩内纵筋、箍筋均未屈服,斜锚表现出稳定的锚固性能。斜锚短桩基础受力较小时,桩锚间的锚固作用主要由钢筋直锚段的黏结作用承担;随着荷载逐渐增加,锚固作用则主要由锚固板端头的承压作用承担,锚杆肋间斜向应力与短桩相应位置斜截面切应力τ_α叠加,使得锚筋周围混凝土裂缝发生偏转,加剧混凝土裂缝向桩表面发展。研究成果可为复合型基础的设计提供借鉴,并为其变形特性与破坏机制研究提供参考。

关键词：斜锚短桩基础锚固板节点受力特性破坏机制

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小样本语义分析的漏洞实体抽取方法

信息安全研究 2025年第3期11卷 265-274页

作者：丁全张磊黄帅查正朋陶陶国网安徽省电力有限公司电力科学研究院合肥230601 中国科学技术大学信息科学技术学院合肥230026 中国科学技术大学先进技术研究院合肥230031 安徽工业大学计算机科学与技术学院安徽马鞍山243032

目前不同信息安全漏洞库标准各异,漏洞数据侧重点不同,关系相对独立,难以快速全面地获取高价值漏洞信息,需建立统一的漏洞实体标准,因此重点对漏洞数据中的实体抽取技术进行研究.大部分漏洞数据以非结构化中英文混合的自然语言形式呈现... 详细信息

目前不同信息安全漏洞库标准各异,漏洞数据侧重点不同,关系相对独立,难以快速全面地获取高价值漏洞信息,需建立统一的漏洞实体标准,因此重点对漏洞数据中的实体抽取技术进行研究.大部分漏洞数据以非结构化中英文混合的自然语言形式呈现,基于规则的方法泛化性不强,基于人工智能的方法占用资源过高且依赖大量标注数据,为解决以上问题,提出一种小样本语义分析的漏洞实体抽取方法.该方法使用BERT(bidirectional encoder representations from transformers)预训练漏洞描述数据得到漏洞领域内的预训练模型,以更好地理解漏洞数据,减少对大量标注数据的依赖,此外,采用增量学习的自监督方式提高标注数据非常有限(1785个标注样本).所提模型抽取了漏洞领域中12类漏洞实体,实验结果表明,所提方法在漏洞实体抽取的效果上优于其他抽取模型,F1值达到0.8643,整体的识别性能较高,实现了对漏洞实体的精确抽取.

关键词：小样本语义分析漏洞实体抽取 BERT CRF

乡镇生活污水处理厂抗生素污染水平及生态风险评价

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环境科学 2025年第1期46卷 296-304页

作者：唐涛涛赵志勇王胤乔晓娟顾鲍超王玮琦曲艳慧中国市政工程西南设计研究总院有限公司成都610084

抗生素的滥用使得大量抗生素进入污水处理厂中,但乡镇污水处理厂中抗生素的污染尚未引起重视.为了解乡镇污水处理厂中抗生素的污染水平及去除特性,考察了15座乡镇污水处理厂进出水中15种抗生素的污染水平和去除效率,并评估了其对水生生... 详细信息

抗生素的滥用使得大量抗生素进入污水处理厂中,但乡镇污水处理厂中抗生素的污染尚未引起重视.为了解乡镇污水处理厂中抗生素的污染水平及去除特性,考察了15座乡镇污水处理厂进出水中15种抗生素的污染水平和去除效率,并评估了其对水生生物和人体健康构成的风险.结果表明,进出水中四环素类抗生素(TCs)检出浓度最高,四环素(TC)和土霉素(OTC)最高检出浓度可达(4 943.69±4.31)ng·L^(-1)和(3 907.81±52.04)ng·L^(-1).在乡镇污水处理厂中,A/O和A^(2)/O工艺对抗生素的去除能力强于MBR工艺.生态风险评估表明,TCs和喹诺酮类抗生素(FQs)具有较大的风险商值,会对水生生物造成中高风险;而磺胺类抗生素(SAs)对水生生物造成低风险.虽然抗生素会对水生生物造成风险,但对人体健康的风险可忽略不计.研究结果可为今后乡镇污水处理厂工艺的升级改造和地区抗生素排放标准的制定提供支撑.

关键词：抗生素污水处理厂(WWTPs) 污染水平去除效率生态风险评估

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脉冲电场预处理提取甜菜糖的研究进展

食品与发酵工业 2025年第2期51卷 365-371页

作者：张楠刘湘裕陶陶祝祥威曾新安滕永欣湖北工业大学生命科学与健康工程学院湖北武汉430068 华南理工大学食品科学与工程学院广东广州510641

甜菜是我国制得蔗糖的主要原料之一,而甜菜制糖的传统热水提取法存在提取时间长、能耗高、提取率低等问题,不符合绿色环保的可持续发展理念。脉冲电场(pulsed electric field,PEF)辅助提取被公认为一种可靠的提取手段,具有短时、非热、... 详细信息

甜菜是我国制得蔗糖的主要原料之一,而甜菜制糖的传统热水提取法存在提取时间长、能耗高、提取率低等问题,不符合绿色环保的可持续发展理念。脉冲电场(pulsed electric field,PEF)辅助提取被公认为一种可靠的提取手段,具有短时、非热、高效等特点,用于甜菜制糖已有不少研究。该文概述国内外使用PEF预处理提取甜菜糖的相关应用,介绍其辅助提取的作用机制和影响提取率的主要因素,并对PEF提取应用做分析与展望,以期为实际生产提供理论指导。

关键词：脉冲电场甜菜制糖提取

Experimental study using the dilution incubation method to assess water biostability

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Journal of Environmental Sciences 2014年第10期26卷 1994-2000页

作者： Qiuhua Wang tao tao Kunlun Xin College of Environmental Science and Engineering Tongji University School of Civil Engineering and Architecture East China Jiaotong University

Water biostability is of particular concern to water supply as a major limiting factor for heterotrophic bacterial growth in water distribution systems. This study focused on bacterial growth dynamics in the series dilution of water samples with TOC（total organic carbon） values determined beforehand. The results showed that the specific growth rate of Pseudomonas fluorescens P17 varied dramatically and irregularly with TOC value when TOC concentrations were low enough during the initial periods of incubation under given conditions. According to this relationship between bacterial growth rate and TOC, a dilution incubation method was designed for the study of water biostability. With the method under a given condition, a turning-point TOC value was found at a relatively fixed point in the curve between bacterial growth rate and TOC of water sample, and the variation of growth rate had different characteristics below the turning-point TOC value relative to that over this value. A turning-point TOC value similarly existed in all experiments not only with tap water, but also with acetate and mixed solutions. And in the dilution incubation method study, the affections were analyzed by condition factors such as inoculum amount,incubation time and nature of the organic carbon source. In very low organic carbon water environments, the variation characteristics of bacterial growth rate will be useful to further understand the meaning of water biostability.

关键词： Water biostability Heterotrophic bacteria Bacterial growth rate Dilution incubation method Total growth organic carbon

Numerical Solution to Optimal Feedback Control by Dynamic Programming Approach:A Local Approximation Algorithm

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Journal of Systems Science & Complexity 2017年第4期30卷 782-802页

作者： GUO Bao-Zhu WU tao-tao Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper considers optimal feedback control for a general continuous time finite-dimensional deterministic system with finite horizon cost functional. A practically feasible algorithm to calculate the numerical solution of the optimal feedback control by dynamic programming approach is developed. The highlights of this algorithm are: a) It is based on a convergent constructive algorithm for optimal feedback control law which was proposed by the authors before through an approximation for the viscosity solution of the time-space discretization scheme developed by dynamic programming method; b) The computation complexity is significantly reduced since only values of viscosity solution on some local cones around the optimal trajectory are calculated. Two numerical experiments are presented to illustrate the effectiveness and fastness of the algorithm.

关键词： Curse of dimensionality Hamilton-Jacobi-Bellman equation optimal feedback control upwind finite difference viscosity solutions

Localization of q-form fields on a de Sitter brane in chameleon gravity

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Frontiers of physics 2024年第3期19卷 11-18页

作者： Yi Zhong tao-tao Sui School of Physics and Electronics Science Hunan UniversityChangsha 410082China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory of Quantum Theory and Applications of MoELanzhou UniversityLanzhou 730000China College of Physics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Recently,it was found that the vector field can be naturally localized on the thick brane in chameleon *** this work,we extend this study to encompass de Sitter brane *** focus on the localization of q-form *** scalar and vector fields can be localized on the de Sitter brane,while the KR field cannot be *** condition for localization of the scalar and vector fields is ***,we investigate the localization characteristics in two examples with given conformal factor b(ϕ).In the first case,the effective potentials and KK modes of the matter fields are obtained asymmetric even though the de Sitter brane has Z2 *** the second case,volcano-like effective potentials are generated in the de Sitter brane model.

关键词： brane q-form field chameleon gravity

Degradation of organics using LaFeO_(3)as a persulfate activator under low-intensity ultra-violet-light irradiation:Catalytic performance and mechanism

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Journal of Rare Earths 2022年第7期40卷 1043-1052页

作者： Yumei Li Jian Fan Xiaonan Feng tao tao School of Environment Huazhong University of Science and TechnologyWuhan 430074China School of Energy and Environment Inner Mongolia University of Science and TechnologyBaotou 014010China

ABO_(3)-type perovskite oxides with abounding defect structures and diverse physical chemistry attributes have been extensively studied in heterogeneous *** LaFeO_(3)perovskites fabricated via the sol-gel method were used as peroxydisulfate(PDS)activators for methylene blue(MB)degradation under low-intensity ultra-violet(UV)-light to evaluate the degradation efficiency of organic pollutants and *** results indicate that under low-intensity UV irradiation,the developed UV/LaFeO_(3)/PDS system shows excellent degradation ability of organic pollutants in a wide pH *** spin resonance and radical quenching experiments verify that SO_(4)^(·-),·OH,h^(+)and ^(1)O_(2)are generated during the activation process,and ^(1)O_(2)plays a dominant role in MB *** of low oxidation state Fe(Ⅱ)and O_(2)^(2-)/O^(-)on the LaFeO_(3)surface shows that oxygen vacancy,as the electron transfer mediator,enhances the redox cycle efficiency of Fe(Ⅱ)/Fe(Ⅲ).Photogenerated electrons of LaFeO_(3)involved in the cyclic transformation of Fe(Ⅱ)/Fe(Ⅲ)and PDS activation further increase the number of active radicals and thus promote the synergistic effect of photocatalytic coupled with sulfate radicalbased advanced oxidation processes.

关键词： LaFeO_(3) Peroxydisulfate Singlet oxygen Low-intensity UV-light Rare earths

Oxidation behavior of in-situ Al_2O_3/TiAl composites at 900°C in static air

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 339-344页

作者： tao-tao Ai Fen Wang Xiao-ming Feng Department of Materials Science and Engineering Shaanxi University of Technology Hanzhong 723003 China School of Materials Science and Engineering Shaanxi University of Science and Technology Xi＇an 710021 China

In-situ Al2O3/TiAl composites were successfully synthesized from the starting powders of Ti, Al, TiO2 and Nb2O5. The oxidation behavior of the composites at 900℃ in static air was investigated. The results indicate that the composite samples present a much lower oxidation mass gain. Under long-time intensive oxidation exposure, the formed oxide scale is multi-layer. The formation of the outer TiO2 layer is fine and dense, the internal Al2O3 scale has good adhesiveness with the outer TiO2 scale, and the TiO2＋Al2O3 mixed layer forming the protective oxide scale is favorable for the improvement of oxidation resistance. It is believed that the incorporation of Al2O3 particulates into the metal matrix decreases the coefficient of thermal expansion of the substrate, and forms a local three-dimensional network structure that can hold the oxide scale. The formation of the oxide scale with finer particle size, stronger adherence, less micro-defects and slower growth rate can contribute to the improvement of oxidation resistance. Nb element plays an important role in reducing the internal oxidation action of the materials, restraining the growth of TiO2 crystals and promoting the stable formation of the Al2O3-riched layer, which is beneficial to improve the oxidation properties.

关键词： intermetallic matrix composites alumina oxidation resistance scale spallation high temperature