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实验教学中心在科研训练和学科竞赛管理方面的探索与实践 被引量:6
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作者 李洁 赖瑢 +7 位作者 肖华 胡水 陈滔 李厚金 许先芳 胡谷平 陈洪燕 朱芳 《大学化学》 CAS 2024年第4期13-18,共6页
创新型人才培养是实现高水平科技自立自强的必然要求,大学生的科研训练和实验竞赛对创新型人才培养发挥了重要作用。本文结合中山大学化学国家级实验教学示范中心建设的实际情况,对近年来组织实施本科生开展创新实验项目和学科竞赛的情... 创新型人才培养是实现高水平科技自立自强的必然要求,大学生的科研训练和实验竞赛对创新型人才培养发挥了重要作用。本文结合中山大学化学国家级实验教学示范中心建设的实际情况,对近年来组织实施本科生开展创新实验项目和学科竞赛的情况、遇到的问题及取得的成效进行介绍和分析,探讨实验教学中心如何发挥资源优势,更好地管理和组织本科生的科研训练和学科竞赛,有效培养大学生的科研思维和实践能力,进一步提升创新型人才的培养水平。 展开更多
关键词 创新型人才 科研训练 学科竞赛 实验教学中心
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以整体搬迁为契机,推动化学实验教学中心高质量发展——以中山大学化学国家级实验教学示范中心为例 被引量:1
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作者 赖瑢 李洁 +6 位作者 许先芳 胡水 陈滔 李厚金 胡谷平 陈洪燕 朱芳 《大学化学》 CAS 2024年第4期33-39,共7页
为配合学校“三校区五校园”办学格局的整体部署,中山大学化学国家级实验教学示范中心积极推进整体搬迁,在学校和化学学院的大力支持下,完成了新的空间布局和实验室优化升级,全面提升了综合实力。中心搬迁调整历时2年,硬件条件得到了飞... 为配合学校“三校区五校园”办学格局的整体部署,中山大学化学国家级实验教学示范中心积极推进整体搬迁,在学校和化学学院的大力支持下,完成了新的空间布局和实验室优化升级,全面提升了综合实力。中心搬迁调整历时2年,硬件条件得到了飞跃式提升,并结合学校新形势、新布局,与时俱进,构建简洁高效科学的管理系统,推动实验教学中心持续发展,开创了中心“高质量办学”新发展格局。 展开更多
关键词 化学国家级实验教学示范中心 搬迁 持续发展 实验教学体系
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TAO患者眼眶脂肪组织中脂肪特异性磷脂酶A2 mRNA表达水平分析 被引量:4
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作者 朱昭亮 陈涛 +1 位作者 田冰玉 张华 《国际眼科杂志》 CAS 北大核心 2018年第7期1333-1335,共3页
目的:分析甲状腺相关眼病(TAO)患者与正常人眼眶脂肪组织中脂肪特异性磷脂酶A2(Ad PLA)mRNA表达水平差异性。方法:选取2016-12/2017-12在本院进行眼眶减压手术的37例37眼TAO(静止期Ⅲ级)患者作为观察组,选取同期正常眼眶脂肪组织35例35... 目的:分析甲状腺相关眼病(TAO)患者与正常人眼眶脂肪组织中脂肪特异性磷脂酶A2(Ad PLA)mRNA表达水平差异性。方法:选取2016-12/2017-12在本院进行眼眶减压手术的37例37眼TAO(静止期Ⅲ级)患者作为观察组,选取同期正常眼眶脂肪组织35例35眼为对照组,其来源为美容、眼袋切除手术和上睑下垂矫正手术者;使用眼球突出计检测观察组与对照组选取脂肪一侧眼球突出度,并计算两组对象BMI状况,使用西门子emotion16排螺旋CT对两组对象眼眶行CT检测,使用Image J检测选取脂肪一侧眼部脂肪体积状况,Real time PCR法检测眼眶脂肪组织内Ad PLA mRNA表达状况。结果:观察组与对照组平均年龄、BMI及性别对比差异均无统计学意义(P>0.05);观察组患眼内脂肪含量、眼球突出度及组织内Ad PLA mRNA表达量分别为32.21±1.85m L、19.97±1.56mm、0.04±0.01高于对照组的24.05±1.64m L、14.07±1.48mm、0.01±0.003,差异均有统计学意义(P<0.05)。结论:TAO患者眼内脂肪含量、眼球突出度及组织内Ad PLA mRNA表达量均比正常人高,TAO患者眼部脂肪组织内Ad PLA表达量升高造成了其脂肪水解量降低,脂肪堆积量增大使其眼球突出程度加重。 展开更多
关键词 甲状腺相关眼病 脂肪水解 眼球突出 脂肪特异性磷脂酶A2
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含不同初始织构的Mg−Gd−Y−Zn−Zr合金热轧板材的显微组织和力学性能
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作者 陈汉 胡璋 +3 位作者 韩宇翔 陈韬 刘楚明 陈志永 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第6期1804-1816,共13页
通过光学显微镜、扫描电子显微镜、电子背散射衍射、透射电子显微镜和拉伸试验研究含不同初始织构的Mg−4.7Gd−3.4Y−1.2Zn−0.5Zr(质量分数,%)合金热轧板材的显微组织和力学性能。结果表明,初始织构为0001//RD(板材轧向)的板材获得相对较... 通过光学显微镜、扫描电子显微镜、电子背散射衍射、透射电子显微镜和拉伸试验研究含不同初始织构的Mg−4.7Gd−3.4Y−1.2Zn−0.5Zr(质量分数,%)合金热轧板材的显微组织和力学性能。结果表明,初始织构为0001//RD(板材轧向)的板材获得相对较粗的晶粒和双峰基面织构;而初始织构为0001//TD(板材横向)的板材动态再结晶程度更高,因此,获得更细的晶粒尺寸和较强的0001//ND基面织构。此外,在两种板材中均发现沿RD拉长的不规则形状LPSO相,这种LPSO相导致各向异性的承载强化行为,并进一步引起板材的屈服各向异性。对强化机理的分析表明,晶界强化对轧制板材的强化效果最好。由于具有较小的晶粒尺寸和LPSO相带来的承载强化效果,初始织构为0001//TD的板材在RD方向上获得最高的屈服强度。 展开更多
关键词 Mg−Gd−Y−Zn−Zr合金 织构 LPSO相 力学性能 强化机理
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Analysis of the joint detection capability of the SMILE satellite and EISCAT-3D radar 被引量:2
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作者 JiaoJiao Zhang TianRan Sun +7 位作者 XiZheng Yu DaLin Li Hang Li JiaQi Guo ZongHua Ding tao chen Jian Wu Chi Wang 《Earth and Planetary Physics》 EI CSCD 2024年第1期299-306,共8页
The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology... The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology to perform large-scale imaging of the Earth’s magnetosheath and polar cusp regions.It uses a high-precision ultraviolet imager to image the overall configuration of the aurora and monitor changes in the source of solar wind in real time,using in situ detection instruments to improve human understanding of the relationship between solar activity and changes in the Earth’s magnetic field.The SMILE satellite is scheduled to launch in 2025.The European Incoherent Scatter Sciences Association(EISCAT)-3D radar is a new generation of European incoherent scatter radar constructed by EISCAT and is the most advanced ground-based ionospheric experimental device in the high-latitude polar region.It has multibeam and multidirectional quasi-real-time three-dimensional(3D)imaging capabilities,continuous monitoring and operation capabilities,and multiple-baseline interferometry capabilities.Joint detection by the SMILE satellite and the EISCAT-3D radar is of great significance for revealing the coupling process of the solar wind–magnetosphere–ionosphere.Therefore,we performed an analysis of the joint detection capability of the SMILE satellite and EISCAT-3D,analyzed the period during which the two can perform joint detection,and defined the key scientific problems that can be solved by joint detection.In addition,we developed Web-based software to search for and visualize the joint detection period of the SMILE satellite and EISCAT-3D radar,which lays the foundation for subsequent joint detection experiments and scientific research. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite European Incoherent Scatter Sciences Association(EISCAT)-3D radar joint detection
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腰凳型婴幼儿背带压力测试与分析
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作者 陈俊虹 陶晨 +2 位作者 洪兴华 金姝 方帅军 《毛纺科技》 CAS 北大核心 2024年第1期116-121,共6页
为改善腰凳型婴幼儿背带的服装压力分布不均现象,采用自行研发的服装压力测量系统,在人台肩部、背部和腰部共12个测量点分别植入薄膜型压力传感器并测量压力值。结果表明,穿着腰凳型背带时肩部压力最大、腰部次之、背部最小,各部位压力... 为改善腰凳型婴幼儿背带的服装压力分布不均现象,采用自行研发的服装压力测量系统,在人台肩部、背部和腰部共12个测量点分别植入薄膜型压力传感器并测量压力值。结果表明,穿着腰凳型背带时肩部压力最大、腰部次之、背部最小,各部位压力随婴儿体重增加而增加,总压力超出婴儿体重;同一负重水平下,穿着摩擦因数较大的服装面料时,背带在人体各部位上造成的压力较小;在同一人体部位、不同测量点上,随负重水平上升而出现压力分化现象。在各个部位的分化点添加高密度海绵垫片,各部位压力不匀得到有效缓解,对于相关产品的改进设计与研究具有重要启发意义。 展开更多
关键词 腰凳型婴幼儿背带 服装压力 压力优化 传感器
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Combining stochastic density functional theory with deep potential molecular dynamics to study warm dense matter 被引量:1
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作者 tao chen Qianrui Liu +2 位作者 Yu Liu Liang Sun Mohan chen 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期44-57,共14页
In traditional finite-temperature Kohn–Sham density functional theory(KSDFT),the partial occupation of a large number of high-energy KS eigenstates restricts the use of first-principles molecular dynamics methods at ... In traditional finite-temperature Kohn–Sham density functional theory(KSDFT),the partial occupation of a large number of high-energy KS eigenstates restricts the use of first-principles molecular dynamics methods at extremely high temperatures.However,stochastic density functional theory(SDFT)can overcome this limitation.Recently,SDFT and the related mixed stochastic–deterministic density functional theory,based on a plane-wave basis set,have been implemented in the first-principles electronic structure software ABACUS[Q.Liu and M.Chen,Phys.Rev.B 106,125132(2022)].In this study,we combine SDFT with the Born–Oppenheimer molecular dynamics method to investigate systems with temperatures ranging from a few tens of eV to 1000 eV.Importantly,we train machine-learning-based interatomic models using the SDFT data and employ these deep potential models to simulate large-scale systems with long trajectories.Subsequently,we compute and analyze the structural properties,dynamic properties,and transport coefficients of warm dense matter. 展开更多
关键词 STOCHASTIC theory FUNCTIONAL
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Product family modeling technology for customized cosmetic packaging design based on basic-element theory 被引量:1
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作者 tao chen Ding-Bang Luh Jinguang Wang 《Journal of dermatologic science and cosmetic technology》 2024年第1期2-12,共11页
Background:As the market demands change,SMEs(small and medium-sized enterprises)have long faced many design issues,including high costs,lengthy cycles,and insufficient innovation.These issues are especially noticeable... Background:As the market demands change,SMEs(small and medium-sized enterprises)have long faced many design issues,including high costs,lengthy cycles,and insufficient innovation.These issues are especially noticeable in the domain of cosmetic packaging design.Objective:To explore innovative product family modeling methods and configuration design processes to improve the efficiency of enterprise cosmetic packaging design and develop the design for mass customization.Methods:To accomplish this objective,the basic-element theory has been introduced and applied to the design and development system of the product family.Results:By examining the mapping relationships between the demand domain,functional domain,technology domain,and structure domain,four interrelated models have been developed,including the demand model,functional model,technology model,and structure model.Together,these models form the mechanism and methodology of product family modeling,specifically for cosmetic packaging design.Through an analysis of a case study on men’s cosmetic packaging design,the feasibility of the proposed product family modeling technology has been demonstrated in terms of customized cosmetic packaging design,and the design efficiency has been enhanced.Conclusion:The product family modeling technology employs a formalized element as a module configuration design language,permeating throughout the entire development cycle of cosmetic packaging design,thus facilitating a structured and modularized configuration design process for the product family system.The application of the basic-element principle in product family modeling technology contributes to the enrichment of the research field surrounding cosmetic packaging product family configuration design,while also providing valuable methods and references for enterprises aiming to elevate the efficiency of cosmetic packaging design for the mass customization product model. 展开更多
关键词 Packaging design Cosmetic packaging Product family modeling technology Basic-element theory Design for mass customization
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Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions
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作者 Yuxue Mu Ning Zhang +7 位作者 Dongyu Wei Guoqing Yang Lilingxuan Yao Xinyue Xu Yang Li Junhui Xue Zuoming Zhang tao chen 《Neural Regeneration Research》 SCIE CAS 2025年第7期2116-2128,共13页
A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to ... A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness. 展开更多
关键词 glial fibrous acidic protein GLIOSIS Müller cells nerve growth factor neural differentiation neurodegeneration proteomic retinal degeneration retinal outer nuclear layer simulated weightlessness
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Effect of substrate temperature and oxygen plasma treatment on the properties of magnetron-sputtered CdS for solar cell applications
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作者 Runxuan Zang Haolin Wang +9 位作者 Xiaoqi Peng Ke Li Yuehao Gu Yizhe Dong Zhihao Yan Zhiyuan Cai Huihui Gao Shuwei Sheng Rongfeng Tang tao chen 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期22-33,I0010,共13页
Cadmium sulfide(CdS)is an n-type semiconductor with excellent electrical conductivity that is widely used as an electron transport material(ETM)in solar cells.At present,numerous methods for preparing CdS thin films h... Cadmium sulfide(CdS)is an n-type semiconductor with excellent electrical conductivity that is widely used as an electron transport material(ETM)in solar cells.At present,numerous methods for preparing CdS thin films have emerged,among which magnetron sputtering(MS)is one of the most commonly used vacuum techniques.For this type of technique,the substrate temperature is one of the key deposition parameters that affects the interfacial properties between the target film and substrate,determining the specific growth habits of the films.Herein,the effect of substrate temperature on the microstructure and electrical properties of magnetron-sputtered CdS(MS-CdS)films was studied and applied for the first time in hydrothermally deposited antimony selenosulfide(Sb_(2)(S,Se)_(3))solar cells.Adjusting the substrate temperature not only results in the design of the flat and dense film with enhanced crystallinity but also leads to the formation of an energy level arrangement with a Sb_(2)(S,Se)_(3)layer that is more favorable for electron transfer.In addition,we developed an oxygen plasma treatment for CdS,reducing the parasitic absorption of the device and resulting in an increase in the short-circuit current density of the solar cell.This study demonstrates the feasibility of MS-CdS in the fabrication of hydrothermal Sb_(2)(S,Se)_(3)solar cells and provides interface optimization strategies to improve device performance. 展开更多
关键词 magnetron sputtering CDS substrate heating plasma treatment Sb_(2)(S Se)_(3) thin film solar cell
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Flame-retardant ammonium polyphosphate/MXene decorated carbon foam materials as polysulfide traps for fire-safe and stable lithium-sulfur batteries
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作者 Yang Li Yong-cheng Zhu +5 位作者 Sowjanya Vallem Man Li Seunghyun Song tao chen Long-cheng Tang Joonho Bae 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期313-323,I0008,共12页
Lithium-sulfur(Li-S)batteries are one of the most promising modern-day energy supply systems because of their high theoretical energy density and low cost.However,the development of high-energy density Li-S batteries ... Lithium-sulfur(Li-S)batteries are one of the most promising modern-day energy supply systems because of their high theoretical energy density and low cost.However,the development of high-energy density Li-S batteries with high loading of flammable sulfur faces the challenges of electrochemical performance degradation owing to the shuttle effect and safety issues related to fire or explosion accidents.In this work,we report a three-dimensional(3D)conductive nitrogen-doped carbon foam supported electrostatic self-assembled MXene-ammonium polyphosphate(NCF-MXene-APP)layer as a heat-resistant,thermally-insulated,flame-retardant,and freestanding host for Li-S batteries with a facile and costeffective synthesis method.Consequently,through the use of NCF-MXene-APP hosts that strongly anchor polysulfides,the Li-S batteries demonstrate outstanding electrochemical properties,including a high initial discharge capacity of 1191.6 mA h g^(-1),excellent rate capacity of 755.0 mA h g^(-1)at 1 C,and long-term cycling stability with an extremely low-capacity decay rate of 0.12%per cycle at 2 C.More importantly,these batteries can continue to operate reliably under high temperature or flame attack conditions.Thus,this study provides valuable insights into the design of safe high-performance Li-S batteries. 展开更多
关键词 FLAME-RETARDANT MXene Ammonium polyphosphate Safety Lithium-sulfur battery
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基于变形网格的织物悬垂形态模拟
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作者 曹竞哲 陶晨 白琳琳 《纺织学报》 EI CAS CSCD 北大核心 2024年第6期59-67,共9页
为快速有效地模拟织物下垂过程、再现真实织物的悬垂形态解决织物约束形态的仿真问题,提出一个变形网格模型用于再现织物悬垂。在模型理论方面,围绕约束因子与衰减因子构建织物内部约束,通过接触-抵消机制复现织物柔性体与刚性平面的接... 为快速有效地模拟织物下垂过程、再现真实织物的悬垂形态解决织物约束形态的仿真问题,提出一个变形网格模型用于再现织物悬垂。在模型理论方面,围绕约束因子与衰减因子构建织物内部约束,通过接触-抵消机制复现织物柔性体与刚性平面的接触。在模型精度上,从网格规模和推演算法2个方面展开探讨,提出了合理的网格规模以达成效果与资源的平衡,并通过三阶泰勒展开减小了运算误差,提升了算法精度。本研究提出的变形网格模型,将悬垂视为动态变化的过程,实现了悬垂形态与悬垂过程的统一。模拟实验表明,真实织物内部的相互作用在模型理论及参数中得到了高度凝练的表达,体现模型特性的虚拟悬垂系数完整覆盖其实际取值区间,波纹不匀作为另一重要形态指标也得到充分表现,模型算法的精度较常规方法提升一个数量级。 展开更多
关键词 变形网格 织物模拟 织物悬垂 悬垂系数 悬垂不匀
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Influence of High-Pressure Induced Lattice Dislocations and Distortions on Thermoelectric Performance of Pristine SnTe
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作者 郑博文 陈涛 +5 位作者 孙海瑞 杨曼曼 杨兵超 陈欣 张永胜 刘晓兵 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期61-68,共8页
As a sister compound of PbTe, SnTe possesses the environmentally friendly elements. However, the pristine SnTe compounds suffer from the high carrier concentration, the large valence band offset between the L and Σpo... As a sister compound of PbTe, SnTe possesses the environmentally friendly elements. However, the pristine SnTe compounds suffer from the high carrier concentration, the large valence band offset between the L and Σpositions and high thermal conductivity. Using high-pressure and high-temperature technology, we synthesized the pristine SnTe samples at different pressures and systemically investigated their thermoelectric properties.High pressure induces rich microstructures, including the high-density dislocations and lattice distortions, which serve as the strong phonon scattering centers, thereby reducing the lattice thermal conductivity. For the electrical properties, pressure reduces the harmful high carrier concentration, due to the depression of Sn vacancies.Moreover, pressure induces the valence band convergence, reducing the energy separation between the L and Σpositions. The band convergence and suppressed carrier concentration increase the Seebeck coefficient. Thus, the power factors of pressure-sintered compounds do not deteriorate significantly under the condition of decreasing electrical conductivity. Ultimately, for a pristine SnTe compound synthesized at 5 GPa, a higher ZT value of 0.51 is achieved at 750 K, representing a 140% improvement compared to the value of 0.21 obtained using SPS. Therefore, the high-pressure and high-temperature technology is demonstrated as an effectively approach to optimize thermoelectric performance. 展开更多
关键词 COEFFICIENT PROPERTIES POSITIONS
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Data-Driven Active Disturbance Rejection Control of Plant-Protection Unmanned Ground Vehicle Prototype: A Fuzzy Indirect Iterative Learning Approach
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作者 tao chen Ruiyuan Zhao +1 位作者 Jian chen Zichao Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1892-1894,共3页
Dear Editor,This letter proposes a fuzzy indirect iterative learning(FIIL)active disturbance rejection control(ADRC)scheme to address the impact of uncertain factors of plant-protection unmanned ground vehicle(UGV),in... Dear Editor,This letter proposes a fuzzy indirect iterative learning(FIIL)active disturbance rejection control(ADRC)scheme to address the impact of uncertain factors of plant-protection unmanned ground vehicle(UGV),in which ADRC is a data-driven model-free control algorithm that only relies on the input and output data of the system.Based on the established nonlinear time-varying dynamic model including dynamic load(medicine box),the FIIL technology is adopted to turn the bandwidth and control channel gain online,in which the fuzzy logic system is used to update the gain parameters of iterative learning in real time.Simulation and experiment show the FIIL-ADRC scheme has better control performance. 展开更多
关键词 Active scheme ITERATIVE
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Minimalistic approach to left atrial appendage occlusion guided by cardiac computed tomography angiography
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作者 Xian-Sai MENG Qing-Song WANG +7 位作者 Xin-Yan WANG Xu LU Yang MU Jing WANG Ting-Ting SONG Yun-Dai chen tao chen Jun GUO 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第4期431-442,共12页
OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who unde... OBJECTIVE To assess the feasibility and safety of the minimalistic approach to left atrial appendage occlusion(LAAO) guided by cardiac computed tomography angiography(CCTA).METHODS Ninety consecutive patients who underwent LAAO, with or without CCTA-guided, were matched(1:2). Each step of the LAAO procedure in the computed tomography(CT) guidance group(CT group) was directed by preprocedural CT planning. In the control group, LAAO was performed using the standard method. All patients were followed up for 12 months, and device surveillance was conducted using CCTA.RESULTS A total of 90 patients were included in the analysis, with 30 patients in the CT group and 60 matched patients in the control group. All patients were successfully implanted with Watchman devices. The mean ages for the CT group and the control group were 70.0 ± 9.4 years and 68.4 ± 11.9 years(P = 0.52), respectively. The procedure duration(45.6 ± 10.7 min vs. 58.8 ± 13.0 min,P < 0.001) and hospital stay(7.5 ± 2.4 day vs. 9.6 ± 2.8 day, P = 0.001) in the CT group was significantly shorter compared to the control group. However, the total radiation dose was higher in the CT group compared to the control group(904.9 ± 348.0 m Gy vs.711.9 ± 211.2 m Gy, P = 0.002). There were no significant differences in periprocedural pericardial effusion(3.3% vs. 6.3%, P = 0.8) between the two groups. The rate of postprocedural adverse events(13.3% vs. 18.3%, P = 0.55) were comparable between both groups at 12 months follow-up.CONCLUSIONS CCTA is capable of detailed LAAO procedure planning. Minimalistic LAAO with preprocedural CCTA planning was feasible and safe, with shortened procedure time and acceptable increased radiation and contras consumption. For patients with contraindications to general anesthesia and/or transesophageal echocardiography, this promising method may be an alternative to conventional LAAO. 展开更多
关键词 ANESTHESIA matched APPROACH
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In vivo pilot study into superficial microcirculatory characteristics of colorectal adenomas using novel high-resolution magnifying endoscopy with blue laser imaging
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作者 Hai-Bin Dong tao chen +2 位作者 Xiao-Fei Zhang Yu-Tang Ren Bo Jiang 《World Journal of Gastrointestinal Endoscopy》 2024年第4期206-213,共8页
BACKGROUND No studies have yet been conducted on changes in microcirculatory hemody-namics of colorectal adenomas in vivo under endoscopy.The microcirculation of the colorectal adenoma could be observed in vivo by a n... BACKGROUND No studies have yet been conducted on changes in microcirculatory hemody-namics of colorectal adenomas in vivo under endoscopy.The microcirculation of the colorectal adenoma could be observed in vivo by a novel high-resolution magnification endoscopy with blue laser imaging(BLI),thus providing a new insight into the microcirculation of early colon tumors.AIM To observe the superficial microcirculation of colorectal adenomas using the novel magnifying colonoscope with BLI and quantitatively analyzed the changes in hemodynamic parameters.METHODS From October 2019 to January 2020,11 patients were screened for colon adenomas with the novel high-resolution magnification endoscope with BLI.Video images were recorded and processed with Adobe Premiere,Adobe Photoshop and Image-pro Plus software.Four microcirculation parameters:Microcirculation vessel density(MVD),mean vessel width(MVW)with width standard deviation(WSD),and blood flow velocity(BFV),were calculated for adenomas and the surrounding normal mucosa.RESULTS A total of 16 adenomas were identified.Compared with the normal surrounding mucosa,the superficial vessel density in the adenomas was decreased(MVD:0.95±0.18 vs 1.17±0.28μm/μm2,P<0.05).MVW(5.11±1.19 vs 4.16±0.76μm,P<0.05)and WSD(11.94±3.44 vs 9.04±3.74,P<0.05)were both increased.BFV slowed in the adenomas(709.74±213.28 vs 1256.51±383.31μm/s,P<0.05).CONCLUSION The novel high-resolution magnification endoscope with BLI can be used for in vivo study of adenoma superficial microcirculation.Superficial vessel density was decreased,more irregular,with slower blood flow. 展开更多
关键词 ADENOMA MICROCIRCULATION High-resolution magnification endoscopy Blue laser imaging
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科尔沁沙地五角枫变色气象条件及预报方法研究
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作者 贾宁 王一冰 +3 位作者 于静 刘梦迪 陶晨 杨旋 《林业调查规划》 2024年第3期165-170,共6页
对沙地五角枫近6年红叶数据进行数字化处理,得出枫叶变色率及变色规律;结合气象要素资料,研究不同变色期的气象阈值条件;利用不同气象要素与枫叶变色率的相关性对枫叶变色率短期、长期预报方法进行详细研究。研究结果表明:沙地五角枫初... 对沙地五角枫近6年红叶数据进行数字化处理,得出枫叶变色率及变色规律;结合气象要素资料,研究不同变色期的气象阈值条件;利用不同气象要素与枫叶变色率的相关性对枫叶变色率短期、长期预报方法进行详细研究。研究结果表明:沙地五角枫初红日序为10月1日,大部分枫树在10月上旬处于斑红,正红日序为10月15日,枫叶进入斑红和正红的时间受逐日气象条件影响较大;日最低温、日最高温、日均温、日均湿度、日最低地面温度越低,枫叶变色率越高,变色率与日降水量、气温日较差、日照时数呈微弱相关;近10 d累积气温越低、日照时数越多、累积湿度越小、累积降水越少,枫叶变色率越高;长期预报因子为6月平均湿度和9月平均气温、平均日照时数、平均最高温度;根据温度阈值建立了枫叶变色因子方程,结合赏枫天气因子建立了枫红气象指数及服务产品,经检验适用性较好。 展开更多
关键词 沙地五角枫 枫叶变色 气象阈值 预报因子 枫红指数
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2022年6月通辽市强冰雹灾害天气分析
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作者 王一冰 刘梦迪 +2 位作者 贾宁 陶晨 戴爽 《气象水文海洋仪器》 2024年第4期41-44,共4页
为了提高通辽大范围强冰雹天气的短时监测能力和预报预警准确率,文章利用常规观测资料、地面加密资料、FY-4卫星云图、多普勒天气雷达资料等,对2022-06-20通辽市强冰雹灾害天气过程进行了环流背景、层结条件和雷达回波特征的分析。结果... 为了提高通辽大范围强冰雹天气的短时监测能力和预报预警准确率,文章利用常规观测资料、地面加密资料、FY-4卫星云图、多普勒天气雷达资料等,对2022-06-20通辽市强冰雹灾害天气过程进行了环流背景、层结条件和雷达回波特征的分析。结果表明:上层干冷、下层暖湿的不稳定层结,较大的对流有效位能、较小的抑制对流有效位能、适宜的融化层高度及强垂直风切变均是通辽强冰雹发生的有利条件;回波垂直结构具有较高的回波质心、三体散射、低层入流、弱回波区与回波垂悬结构特征,并呈现低层辐合、高层辐散的结构,有较强的上升气流;冰雹回波发展时的垂直累积液态含水量及最大基本反射率均维持在较高值可作为冰雹天气发生的判断依据。研究结果为通辽地区冰雹天气的监测预警技术提供了分析依据。 展开更多
关键词 冰雹 辐合线 三体散射 VIL值
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降低离心压缩机扩压器高度的定子件优化设计 被引量:2
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作者 孙永瑞 陶琛 裴威 《流体机械》 CSCD 北大核心 2023年第5期22-28,共7页
针对现有压缩机组径向尺寸大、机组重量大的问题,对某型离心压缩机模型级开展降低扩压器高度的定子件优化设计,采用拉丁超立方抽样结合神经网络离线预测模型进行全局寻优,解决了压缩机缩减尺寸后出现的弯道高入流速及回流器的短弦长引... 针对现有压缩机组径向尺寸大、机组重量大的问题,对某型离心压缩机模型级开展降低扩压器高度的定子件优化设计,采用拉丁超立方抽样结合神经网络离线预测模型进行全局寻优,解决了压缩机缩减尺寸后出现的弯道高入流速及回流器的短弦长引起的定子件内损失增大的问题。提出了优化目标降维和粗、精细优化相结合的方法,以及筛选出高敏感度参数及关键部件进行重点优化,缩短了优化周期。结果表明:最终方案CFD效率提升了0.71%,试验测试效率提高了1.3%,验证了优化设计方法有效;经过对比分析,建议压缩机缩减设计时保持b_(4)不变,增大b_(5)以降低回流器入口气体流速,设置b6与b5尺寸相当以降低二次弯道损失,同时,调节回流器叶片安装角度使之与气流匹配即可实现较高的级效率。 展开更多
关键词 离心压缩机 扩压器 缩减 优化设计
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基于流形学习的锂离子电池故障诊断方法 被引量:1
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作者 贺兴 陶陈 +1 位作者 常春 姜久春 《电池》 CAS 北大核心 2023年第3期262-266,共5页
锂离子电池容易受到滥用和老化等因素的影响。电池系统故障会导致车辆安全事故发生,为保障车辆的正常运行,对锂离子电池故障的诊断至关重要。提出一种基于流形学习的锂离子电池故障诊断方法。首先,通过变分模态分解(VMD),对电池的电压... 锂离子电池容易受到滥用和老化等因素的影响。电池系统故障会导致车辆安全事故发生,为保障车辆的正常运行,对锂离子电池故障的诊断至关重要。提出一种基于流形学习的锂离子电池故障诊断方法。首先,通过变分模态分解(VMD),对电池的电压信号进行分解和重构;然后,基于重构信号,通过局部线性嵌入算法提取无量纲特征参数;再使用局部离群因子(LOF)算法检测故障电池;最后,将故障检测时间与真实车辆的报警时间进行比较。该方法能及时准确地检测出故障电池,相较于电池管理系统,提前17个采样点发出故障预警。 展开更多
关键词 锂离子电池 数据驱动 故障诊断 热失控 实车数据
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