检索结果-南通市图书馆

Dental pulp regeneration strategies:A review of status quo and recent advances

在线全文

学校读者我要写书评

暂无评论

Bioactive Materials 2024年第8期38卷 258-275页

作者： Xin-Lu Li Wei fan Bing fan The State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool&Hospital of StomatologyWuhan University237 Luoyu Road430079WuhanChina

Microorganisms,physical factors such as temperature or mechanical injury,and chemical factors such as free monomers from composite resin are the main causes of dental pulp *** clinical treatment methods for pulp diseases include the root canal therapy,vital pulp therapy and regenerative endodontic *** endodontic therapy serves the purpose of inducing the regeneration of new functional pulp tissues through autologous revascularization or pulp tissue *** article first discusses the current clinical methods and reviews strategies as well as the research outcomes regarding the pulp *** the in vivo models,the prospects and challenges for regenerative endodontic therapy were further discussed.

关键词： Pulp regeneration Revascularization Scaffold Growth factor Cell-homing

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于伪标签算法的地震事件分类识别方法研究

地震工程学报 2025年第1期47卷 160-167,177页

作者：范晓易王夫运陈飞陈传华江苏省地震局南京地震监测中心站江苏南京210000 中国地震局地球物理勘探中心河南郑州450000 山东省地震局泰安地震监测中心站山东泰安271000

将伪标签算法引入地震类型识别领域,并设计伪标签神经网络法程序,对山东地区2019—2021年M L1.5以上的天然地震、爆破地震、塌陷地震三类事件开展试验。使用优选的有标签样本集预测无标签样本,将其标记为伪标签样本后加入联合训练,并对... 详细信息

将伪标签算法引入地震类型识别领域,并设计伪标签神经网络法程序,对山东地区2019—2021年M L1.5以上的天然地震、爆破地震、塌陷地震三类事件开展试验。使用优选的有标签样本集预测无标签样本,将其标记为伪标签样本后加入联合训练,并对比传统BP神经网络法和支持向量机法,以初步验证伪标签算法在地震类型识别领域的可行性和在小样本条件下的适用性。试验结果表明:影响伪标签神经网络法分类效果的主要因素有已知样本数量和伪标签样本占比。当已知样本数量介于60~120个、伪标签样本占比20%~30%时,其识别效果最佳。在小样本条件下,伪标签神经网络法的识别率相较于传统BP神经网络法提高了2%~8%,与支持向量机法的识别率差值集中在±4%以内。因此,采用伪标签算法弥补部分地区样本库匮乏的不足,实现小样本地震类型识别,具备一定的应用价值。

关键词：伪标签算法地震类型识别神经网络法小样本

Recent progress in the deactivation mechanism of zeolite catalysts in methanol to olefins

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第12期67卷 3934-3943页

作者： Sheng fan Han Wang Sen Wang Mei Dong Weibin fan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China

Methanol to olefins(MTO)as an important reaction in C1 chemistry can effectively transform non-petroleum carbon resources into value-added *** have been widely used as MTO ***,they usually suffer from a rapid deactivation due to bulky coke species production,and thus require continuous regenerations in industrial *** key to design and develop highly stable zeolite catalysts for MTO process is to unravel the deactivation mechanism and clarify the structure–performance relationship of ***,in this mini-review,we investigate the critical intermediate species inducing zeolite deactivation and analyze the formation and evolution pathways of polycyclic aromatic hydrocarbons(PAHs)that are the precursors of carbonaceous *** addition,some methods to alleviate the coking mainly including acid regulation,morphology modification and process optimization,are also summarized.

关键词： methanol to olefins zeolites deactivation mechanism polycyclic aromatic hydrocarbons

Optimization of microstructure design for enhanced sensing performance in flexible piezoresistive sensors

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2024年第6期13卷 711-728页

作者： Xinghao fan Hailong Hu Bin Liao Yaqi Zhang fan Zhang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Research Institute of Aerospace Technology Central South UniversityChangsha 410083China

Flexible piezoresistive strain sensors have received significant attention due to their diverse applications in monitoring human activities and health,as well as in robotics,prosthetics,and human–computer interaction *** the various flexible sensor types,those with microstructure designs are considered promising for strain sensing due to their simple structure,high sensitivity,extensive operational range,rapid response time,and robust *** review provides a concise overview of recent advancements in flexible piezoresistive sensors based on microstructure design for enhanced strain sensing performance,including the impact of microstructure on sensing mechanisms,classification of microstructure designs,fabrication methods,and practical ***,this review delves into the analysis of piezoresistive sensor sensing mechanisms and performance parameters,exploring the relationship between microstructure design and performance ***,an in-depth discussion is presented,focusing on the primary themes of microstructure design classification,process selection,performance characteristics,and specific *** review employs mathematical modeling and hierarchical analysis to emphasize the directionality of different microstructures on performance enhancement and to highlight the performance advantages and applicable features of various microstructure *** conclusion,this review examines the multifunctionality of flexible piezoresistive sensors based on microstructure design and addresses the challenges that still need to be overcome and improved,such as achieving a wide range of stretchability,high sensitivity,and robust *** review summarizes the research directions for enhancing sensing performance through microstructure design,aiming to assist in the advancement of flexible piezoresistive sensors.

关键词： microstructure design sensing performance flexible piezoresistive strain sensors microsensing mechanism

Active generalized predictive control of turbine tip clearance for aero-engines

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2013年第5期26卷 1147-1155页

作者： Peng Kai fan Ding Yang fan Fu Qiang Li Yong School of Power and Energy Northwestern Polytechnical University Aeronautics and Astronautics Engineering College Air Force Engineering University School of Flight Technology Civil Aviation Flight University of China

Active control of turbine blade tip clearance continues to be a concern in design and control of gas turbines. Ever increasing demands for improved efficiency and higher operating temperatures require more stringent tolerances on turbine tip clearance. In this paper, a turbine tip clearance control apparatus and a model of turbine tip clearance are proposed; an implicit active generalized predictive control （GPC）, with auto-regressive （AR） error modification and fuzzy adjustment on control horizon, is presented, as well as a quantitative analysis method of robust per- turbation radius of the system. The active clearance control （ACC） of aero-engine turbine tip clear- ance is evaluated in a lapse-rate take-off transient, along with the comparative and quantitative analysis of the stability and robustness of the active tip clearance control system. The results show that the resultant active tip clearance control system with the improved GPC has favorable steadystate and dynamic performance and benefits of increased efficiency, reduced specific fuel consump- tion, and additional service life.

关键词： Active clearance control(ACC) Aero-engine Aircraft Generalized prcdictivc control (GPC) Global convergence Robust perturbation radius Turbine tip clearance

考虑碳排放优化的多层随机模型预测的配电网新能源电压控制方法

在线全文

学校读者我要写书评

暂无评论

供用电 2025年第1期42卷 72-78页

作者：宋美琪李洪全武浩范岳张鹏商和龙丁浩范宏进国网冀北电力有限公司智能配网中心河北秦皇岛066100 山东电工电气集团新能科技有限公司山东济南250101 山东大学电气工程学院山东济南250061

“电力零碳”是实现“双碳”目标的重要支撑,采用可再生能源发电是实现“电力零碳”的重要举措。电力高比例可再生能源接入配电网给配电网电压控制带来了巨大挑战。同时,风能场站等可再生能源具有高随机性和间歇性等特点,传统电压控制... 详细信息

“电力零碳”是实现“双碳”目标的重要支撑,采用可再生能源发电是实现“电力零碳”的重要举措。电力高比例可再生能源接入配电网给配电网电压控制带来了巨大挑战。同时,风能场站等可再生能源具有高随机性和间歇性等特点,传统电压控制方法在高比例可再生能源渗透的情景下无法取得满意的控制效果。为解决以上电压控制问题,提出了一种基于双层随机模型预测控制的电压控制方法。在所提方法中,变压器和并联电容在上层以小时为周期进行控制,而下层控制器以15 min为控制周期对分布式发电(distributed generation,DG)的输出进行调节。所提方法综合了模型预测控制和随机优化的优点,能实现有效的电压控制效果,并降低碳排放。基于改进IEEE 33节点系统中的仿真结果表明,所提方法能有效协调不同的电压调节设备,在高随机性可再生能源渗透下能取得良好的电压控制效果,保证配电网运行的经济性,有效降低配电网络运行的碳排放。

关键词：配电网电压控制碳排放随机模型预测控制分布式发电

Spatially distributed damage in sandstone under stress-freeze-thaw coupling conditions

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1910-1922页

作者： Lifeng fan Yiding fan Yan Xi Jingwei Gao College of Architecture and Civil Engineering Beijing University of TechnologyBeijing100124China

In the present study,we tried to understand the spatially distributed damage in sandstone samples under the coupled stress-freeze-thaw(SFT)***,uniaxial compressive stresses(i.e.0 MPa,10 MPa,20 MPa,and 25 MPa)were applied to the samples,and then freeze-thaw(FT)cycles(0,8,16,and 24)were performed on the uniaxially stressed samples to realize the SFT ***,real-time CT scanning was conducted to observe the induced *** total porosity was introduced to quantitatively evaluate the damage *** local porosity variation,with the distance from the center of the sandstone sample,was analyzed to understand the spatial distribution of ***,the coupling effects of SFT on the damage gradient were *** results indicate that the porosity rises with FT cycles,and the applied stresses can accelerate the increase in *** damage increases exponentially with the distance from the center of the *** damage presents a spatial gradient distribution,not the commonly used uniform distribution in various *** damage gradient increases with FT cycles,and the increasing rate in damage gradient decreases at uniaxial stress of 0 MPa and 10 MPa first,but the increasing rate in damage gradient increases with FT cycles then at stress increasing to 20 MPa.

关键词： Rock damage Freeze-thaw(FT)cycles Uniaxial stress oupling effects

DNA framework-engineered electrochemical biosensors

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2020年第8期63卷 1130-1141页

作者： fan Li Qian Li Xiaolei Zuo Chunhai fan Institute of Molecular Medicine Renji HospitalSchools of MedicineShanghai Jiao Tong UniversityShanghai 200127China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Self-assembled DNA nanostructures have shown remarkable potential in the engineering of biosensing interfaces,which can improve the performance of various *** particular,by exploiting the structural rigidity and programmability of the framework nucleic acids with high precision,molecular recognition on the electrochemical biosensing interface has been significantly enhanced,leading to the development of highly sensitive and specific biosensors for nucleic acids,small molecules,proteins,and *** this review,we summarize recent advances in DNA framework-engineered biosensing interfaces and the application of corresponding electrochemical biosensors.

关键词： framework nucleic acids biosensing interface electrochemical biosensors biomarkers DNA

在线全文

学校读者我要写书评

暂无评论

道路桥梁钻孔灌注桩施工技术研究

价值工程 2025年第1期44卷 36-38页

作者：范志泉龙岩交通建设集团有限公司龙岩364000

钻孔灌注桩因其适应性强、成本合理、施工便捷,在公路桥梁、港口等工程领域得到广泛应用。然而,其成桩过程复杂,影响质量的因素众多,因此需要严格控制每一环节并全面考虑各种影响因素。本文通过研究东山大桥道路桥梁工程的灌注桩施工,... 详细信息

钻孔灌注桩因其适应性强、成本合理、施工便捷,在公路桥梁、港口等工程领域得到广泛应用。然而,其成桩过程复杂,影响质量的因素众多,因此需要严格控制每一环节并全面考虑各种影响因素。本文通过研究东山大桥道路桥梁工程的灌注桩施工,深入对比分析了旋挖成孔和冲击成孔两种方式的技术特性、工效及成本,旨在为类似工程提供有益参考。通过综合比较不同施工方案,可结合工程需求、施工条件和经济效益,选出最佳方案,进而提升工程质量,降低成本并缩短工期。

关键词：钻孔灌注桩旋挖成孔冲击成孔施工方案

维普期刊数据库博看期刊