检索结果-南通市图书馆

Tuning synergy between nickel and iron in Ruddlesden-Popper perovskites through controllable crystal dimensionalities towards enhanced oxygenevolving activity and stability

引用

Carbon Energy 2024年第6期6卷 113-123页

作者： Haijuan Zhang Daqin Guan Yuxing Gu Hengyue Xu Chunchang Wang Zongping Shao youmin guo School of Materials Science and Technology Anhui UniversityHefeiAnhuiChina Department of Building and Real Estate The Hong Kong Polytechnic UniversityHung HomHong KongChina WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerthWestern AustraliaAustralia State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjingJiangsuChina Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhenGuangdongChina

Ni-Fe-based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction(OER)in water ***,understanding and mastering the synergy of Ni and Fe remain ***,we report that the synergy between Ni and Fe can be tailored by crystal dimensionality of Ni,Fe-contained Ruddlesden-Popper(RP)-type perovskites(La_(0.125)Sr_(0.875))n+1(Ni_(0.25)Fe_(0.75))nO3n+1(n=1,2,3),where the material with n=3 shows the best OER performance in alkaline *** X-ray absorption spectroscopy spectra before and after OER reveal that the material with n=3 shows enhanced Ni/Fe-O covalency to boost the electron transfer as compared to those with n=1 and n=*** experimental investigations demonstrate that the Fe ion is the active site and the Ni ion is the stable site in this system,where such unique synergy reaches the optimum at n=***,as n increases,the proportion of unstable rock-salt layers accordingly decreases and the leaching of ions(especially Sr^(2+))into the electrolyte is suppressed,which induces a decrease in the leaching of active Fe ions,ultimately leading to enhanced *** work provides a new avenue for rational catalyst design through the dimensional strategy.

关键词： crystal dimensionalities oxygen evolution reaction Ruddlesden-Popper perovskites synergy

来源：

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

基于改进YOLOv5的轨道交通障碍物检测算法

引用

电子测量技术 2024年第1期47卷 130-135页

作者：赵鸿亮郭佑民王建鑫杨君兰州交通大学机电技术研究所兰州730070

针对复杂的轨道交通背景下障碍物检测精度低和检测速度慢的问题,提出了一种改进YOLOv5的目标检测网络模型。首先,采用基于注意力机制的轻量级Transformer主干EMO来替换YOLOv5原有backbone中的部分模块,保证轻量化的同时,还能够提高模型... 详细信息

针对复杂的轨道交通背景下障碍物检测精度低和检测速度慢的问题,提出了一种改进YOLOv5的目标检测网络模型。首先,采用基于注意力机制的轻量级Transformer主干EMO来替换YOLOv5原有backbone中的部分模块,保证轻量化的同时,还能够提高模型的准确性和稳定性;其次,使用Focal-EIoU来替换YOLOv5中的CIoU损失函数,以解决CIoU引起的训练效率低、收敛速度慢等问题;最后使用轻量化上采样算子CARAFE来替换YOLOv5算法中原有的上采样层,在没有引入过多参数和计算量的情况下具有更大的感受野,提高了检测精度和检测速度。实验结果表明,该方法相较于原始的YOLOv5网络模型平均精确度提升了11.1%,准确率提升了13%,召回率提升了11.4%,检测速度达到了60.7 fps。所提出的方法在目标检测任务中表现出了较好的性能,有效增强了轨道交通背景下目标检测模型的检测性能。

关键词：异物入侵 YOLOv5 注意力机制损失函数上采样

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于机器视觉的轨道线检测方法

引用

机电工程技术 2024年第5期53卷 162-166页

作者：赵鸿亮郭佑民兰州交通大学机电技术研究所兰州730070

针对现有铁路轨道检测识别算法的准确性和鲁棒性不高的问题,提出了一系列有效的图像处理技术来实现轨道线检测。首先,采用加权平均法对图像进行灰度化处理,以减少计算量并提高计算速度。接着,利用高斯滤波对处理后的灰度图像进行去噪处... 详细信息

针对现有铁路轨道检测识别算法的准确性和鲁棒性不高的问题,提出了一系列有效的图像处理技术来实现轨道线检测。首先,采用加权平均法对图像进行灰度化处理,以减少计算量并提高计算速度。接着,利用高斯滤波对处理后的灰度图像进行去噪处理,以消除噪声干扰,提高后续处理步骤的准确性。然后,应用Sobel算子边缘检测算法从图像中提取边缘信息,有效识别图像中的边缘特征,准确提取轨道线的边缘信息。最后,利用三次函数对提取出的边缘信息进行拟合,得到平滑的轨道线。通过实验证明,所提出的轨道线检测方法显著提高了检测成功率,在轨道线检测任务中表现出良好的性能,并具备准确性和鲁棒性。

关键词：机器视觉边缘检测灰度处理弯轨拟合

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

改性PVDF-HFP基凝胶电解质的合成及锂金属电池性能研究

引用

有色金属材料与工程 2024年第1期45卷 1-9页

作者：程启和王丰张宇郭友敏安徽大学材料科学与工程学院合肥230601 合肥国轩高科动力能源有限公司合肥230041

开发高质量的固态电解质,对制造新一代安全稳定的固态锂金属电池具有重要意义。以聚偏氟乙烯–六氟丙烯(polyvinylidene fluoride-hexafluoropropylene,PVDF-HFP)为聚合物基体,引入MOF-808作为活性填料,采用溶液浇筑法制备了新型凝胶聚... 详细信息

开发高质量的固态电解质,对制造新一代安全稳定的固态锂金属电池具有重要意义。以聚偏氟乙烯–六氟丙烯(polyvinylidene fluoride-hexafluoropropylene,PVDF-HFP)为聚合物基体,引入MOF-808作为活性填料,采用溶液浇筑法制备了新型凝胶聚合物电解质。优化后的凝胶聚合物电解质在室温下的离子电导率高达3.21 mS/cm,电化学稳定窗口可达5.0 V、具有较高的Li^(+)迁移数(0.63)、与锂金属具有良好的界面相容性。组装的磷酸铁锂全电池在0.5 C倍率下循环250次,容量保持率为86.7%。高性能凝胶聚合物电解质对提升锂金属电池的循环稳定性与安全性具有重要的应用价值。

关键词：锂金属电池凝胶聚合物电解质金属有机框架材料 PVDF-HFP

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

大型设备在本科实验教学中的应用

引用

中国冶金教育 2024年第3期 70-71,76页

作者：高倩何刚张惠郭友敏刘艳美安徽大学材料科学与工程学院安徽合肥230601

以静电纺丝实验为例,探讨了大型设备在本科实验教学中的应用。将大型科研设备应用于本科生实验教学,不仅可以提高大型仪器设备的利用率,还可以将教师科研经验反哺教学,通过设计探索性实验内容促进学生自我教育、主动学习,培养综合能力,... 详细信息

以静电纺丝实验为例,探讨了大型设备在本科实验教学中的应用。将大型科研设备应用于本科生实验教学,不仅可以提高大型仪器设备的利用率,还可以将教师科研经验反哺教学,通过设计探索性实验内容促进学生自我教育、主动学习,培养综合能力,提升教学质量。

关键词：科教融合静电纺丝实验教学纳米纤维

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Fast fixed-time three-dimensional terminal guidance with non-concave trajectory constraint

引用

Chinese Journal of Aeronautics 2024年第3期37卷 208-218页

作者： youmin GONG Yanning guo Yueyong LYU Dongyu LI Guangfu MA Department of Control Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Cyber Science and Technology Beihang UniversityBeijing 100191China

Focusing on the non-concave trajectory constraint,a sliding-mode-based nonsingular feedback fast fixed-time three-dimensional terminal guidance of rotor unmanned aerial vehicle landing,planetary landing and spacecraft rendezvous and docking terminal phase with external disturbance is investigated in this ***,a fixed-time observer based on real-time differentiator is developed to compensate for the external disturbance,whose estimation error can converge to zero after a time independent of the initial ***,a sliding surface ensuring fixed-time convergence is *** sliding surface can guarantee that the vehicle achieves a non-concave trajectory,which is better for avoiding collision and maintaining the visibility of the landing site or docking ***,the nonsingular guidance ensuring the fixed-time convergence of the sliding surface is proposed,which is continuous and chatter *** last,three numerical simulations of Mars landing are performed to validate the effectiveness and correctness of the designed scheme.

关键词： Three-dimensional Terminal guidance Non-concave trajectory constraint Fast fixed-time control Sliding mode control

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Quantitative computed tomography analysis for stratifying the severity of Coronavirus Disease 2019

引用

Journal of Pharmaceutical Analysis 2020年第2期10卷 123-129页

作者： Cong Shen Nan Yu Shubo Cai Jie Zhou Jiexin Sheng Kang Liu Heping Zhou youmin guo Gang Niu Department of Medical Imaging The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an710061ShaanxiChina Department of Radiology The Affiliated Hospital of Shaanxi University of Traditional Chinese MedicineXianyang712000ShaanxiChina Department of Radiology Xi'an Chest HospitalXi'an710100ShaanxiChina Department of Radiology Hanzhong Central HospitalHanzhong723000ShaanxiChina Department of CT&MR Imaging Weinan Central HospitalWeinan714000ShaanxiChina Department of Radiology Ankang Central HospitalAnkang725000ShaanxiChina

To examine the feasibility of using a computer tool for stratifying the severity of Coronavirus Disease 2019(COVID-19)based on computed tomography(CT)*** retrospectively examined 44 confirmed COVID-19 *** cases were evaluated separately by radiologists(visually)and through an in-house computer *** degree of lesions was visually scored by the radiologist,as follows,for each of the 5 lung lobes:0,no lesion present;1,1/3 and2/3 *** density was assessed based on the proportion of ground-glass opacity(GGO),consolidation and fibrosis of the *** parameters obtained using the computer tool included lung volume(mL),lesion volume(mL),lesion percentage(%),and mean lesion density(HU)of the whole lung,right lung,left lung,and each *** scores obtained by the radiologists and quantitative results generated by the computer software were tested for correlation.A Chi-square test was used to test the consistency of radiologist-and computer-derived lesion percentage in the right/left lung,upper/lower lobe,and each of the 5 *** results showed a strong to moderate correlation between lesion percentage scores obtained by radiologists and the computer software(r ranged from 0.7679 to 0.8373,P<0.05),and a moderate correlation between the proportion of GGO and mean lesion density(r=-0.5894,P<0.05),and proportion of consolidation and mean lesion density(r=0.6282,P<0.05).Computer-aided quantification showed a statistical significant higher lesion percentage for lower lobes than that assessed by the radiologists(x^2=8.160,P=0.004).Our experiments demonstrated that the computer tool could reliably and accurately assess the severity and distribution of pneumonia on CT scans.

关键词： Quantitative computed tomography(QCT) Coronavirus disease 2019(COVID-19) Severity stratification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Apparent diffusion coefficient in normal and abnormal pattern of intervertebral lumbar discs: initial experience

引用

The Journal of Biomedical Research 2011年第3期25卷 197-203页

作者： Gang Niu Xuewen Yu Jian Yang Rong Wang Shaojuan Zhang youmin guo Department of Diagnostic Radiology the First Hospital of Medical School Xi'an Jiaotong University Xi'an Shaanxi 710061 China

The aim of the present study was to compare the relationship of morphologically defined non-bulging/herni-ated, bulging and herniated intervertebral lumbar discs with quantitative apparent diffusion coefficient （ADC）. Thirty-two healthy volunteers and 28 patients with back pain or sciatica were examined by MRI. All intervertebral lumbar discs from L1 to S1 were classified according to morphological abnormality and degenerated grades. The ADC values of nucleus pulposus （NP） were measured and recorded. The significant differences about mean ADC values of NP were found between non-bulging/herniated discs and bulging discs as well as herniated discs （P 0.05）, whereas there were no significant differences in ADC values between bulging and herniated discs （P 0.05）. Moreover, statistically significant relationship was found in the mean ADC values of NP between ＂non-bulging/herniated and non-degenerated discs＂ and ＂non-bulging/herniated degenerated discs＂ as well as herniated discs （P 0.05）. Linear regression analysis between ADC value and disc level revealed an inverse correlation （r = -0.18）. The ADC map of the NP is a potentially useful tool for the quantitative assessment of componential and molecular alterations accompanied with lumbar disc abnormalities.

关键词： intervertebral lumbar disc apparent diffusion coefficient disc bulging disc herniation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ultrafast laser-chemical modification hybrid fabrication of hydrostatic bearings with a superhydrophobicity solid-liquid interface

引用

Science China(Technological Sciences) 2024年第3期67卷 696-708页

作者： guo MingHui RONG youmin HUANG Yu FENG XiaoLin HU HaiDong WU CongYi ZHANG guoJun State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Faculty of Engineering and Life Sciences Universiti Selangor Bestari JayaSelangor 45600Malaysia

Oil film vortex severely reduces the stability of hydrostatic bearings. A solid-liquid interface with drag and slip properties can weaken the oil film vortex of the bearing. Here, a combined picosecond laser ablation and chemical modification method is proposed to prepare surfaces with microbulge array structure on 6061 aluminum alloy substrates. Because of the low surface energy of the perfluorododecyltriethoxysilane modification and the bulge geometry of the microbulge array structure, the surface shows excellent superhydrophobicity. The optimum contact angle in air for water is 164°, and that for oil is 139°. Two surfaces with “lotus-leaf effect” and “rose-petal effect” were obtained by controlling the processing parameters. The drag reduction properties of superhydrophobic surfaces were systematically investigated with slip lengths of 22.26 and 36.25 μm for deionized water and VG5 lubricant, respectively. In addition, the superhydrophobic surface exhibits excellent mechanical durability and thermal stability. The proposed method provides a new idea for vortex suppression in hydrostatic bearings and improves the stability of bearings in high-speed operation.

关键词： superhydrophobicity surface ultrafast laser drag reduction solid-liquid interface microbulge array structure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

跨学科背景下的新能源领域创新人才培养

引用

时代汽车 2024年第16期 46-48页

作者：查文珂冯子成李进黄家锐郭友敏葛瑞行安徽科技学院机械工程学院先进储能关键技术及可靠性研发中心安徽滁州233100 安徽师范大学化学与材料科学学院分子基材料省级重点实验室安徽芜湖241002 安徽大学材料科学与工程学院杂化材料结构与功能调控教育部重点实验室安徽合肥230601 泰安市安顺矿山设备有限公司山东泰安271024

在跨学科背景下,如何培养新能源领域创新人才引起社会广泛关注。该论文首先总结了新能源技术发展的趋势,然后结合教育理论和实践,提出了促进跨学科合作和创新能力培养的模式和策略。跨学科合作培养在培养新能源创新人才方面具有重要意义... 详细信息

在跨学科背景下,如何培养新能源领域创新人才引起社会广泛关注。该论文首先总结了新能源技术发展的趋势,然后结合教育理论和实践,提出了促进跨学科合作和创新能力培养的模式和策略。跨学科合作培养在培养新能源创新人才方面具有重要意义,为培养出具备跨学科思维和创新能力的新能源领域创新人才,推动新能源技术发展和应用进步提供重要支持。

关键词：跨学科新能源创新人才培养

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：