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Effects of light curing modes and ethanol-wet bonding on dentin bonding properties

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2016年第9期17卷 703-711页

作者： Mu-zi LI Jin-rui WANG Hong LIU Xia WANG Kang GAN Xiu-ju LIU De-li NIU Xiao-qing song School and Hospital of Stomatology Jilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Tooth Development and Remodeling Changchun 130021China

Objective： This study explored the effects of different light curing modes and ethanol-wet bonding on dentin bonding strength and durability. Methods： A total of 54 molars were randomly divided into three groups： Single Bond 2, Gluma Comfort Bond, and N-Bond. Based on the three light-curing modes and presence or absence of eth- anol pretreatment, the samples were assigned to six subgroups： high-light mode, ethanol pretreatment＋high-light mode, soft-start mode, ethanol pretreatment＋soft-start mode, standard mode, and ethanol pretreatment＋standard mode. All samples were bonded with resin based on the experimental groups. After 24 h and 6 months of water storage, a universal testing machine was used to measure microtensile bond strength. Scanning electron microscopy （SEM） was applied to observe mixed layer morphology. Results： The 24-h and 6-month microtensile bond strengths of the ethanol pretreatment groups were significantly higher than those of the non-ethanol pretreatment groups at the same light modes （P〈0.05）. With or without ethanol pretreatment, the microtensile bond strengths of the high-light modes were significantly lower than those of the soft-start modes and standard modes （P〈0.05）. The microtensile bond strengths of samples from the 6-month water storage group significantly decreased compared with those of samples from the 24-h water storage group （P〈0.05）. The soft-start groups and standard groups formed better mixed layers than the high-light mode groups, whereas the ethanol pretreatment groups formed more uniform mixed layers than those without ethanol pretreatment. Conclusions： Ethanol-wet bonding technique, soft-start, and standard modes could improve dentin bonding properties.

关键词： Light curing mode Soft-start Ethanol-wet bonding Scanning electron microscopy (SEM) Bondingstrength

基于电流偏差的永磁同步电机滑模电流解耦控制

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控制理论与应用 2022年第11期39卷 2149-2160页

作者：曾小莉王维庆王海云新疆大学可再生能源发电与并网技术教育部工程研究中心新疆乌鲁木齐830047

永磁同步电机(PMSM)矢量控制的目标是使PMSM表现优良的动态性能和稳态性能,为解决同步旋转坐标下dq轴电流存在耦合,同时传统解耦方法在电感参数失配时解耦效果不佳的问题,提出一种基于电流偏差的永磁同步电机滑模电流解耦控制方法.该方... 详细信息

永磁同步电机(PMSM)矢量控制的目标是使PMSM表现优良的动态性能和稳态性能,为解决同步旋转坐标下dq轴电流存在耦合,同时传统解耦方法在电感参数失配时解耦效果不佳的问题,提出一种基于电流偏差的永磁同步电机滑模电流解耦控制方法.该方法在电流偏差解耦控制电机模型的基础上,保证系统的良好的动态性能,并充分利用偏差解耦结构的灵活性,引入新的Z控制函数,设计滑模控制律,使其运动在滑模阶段,并且呈非线性光滑特性,以保证系统滑动模态,抑制抖振,从而实现dq轴电流较好的解耦效果,同时提高系统在整个运动过程中因参数摄动和外在扰动的鲁棒性,保证系统的动态性能.通过对传统解耦方法和新方法的仿真和实验对比分析,验证所提方法的可行性和有效性.

关键词：永磁同步电机电流解耦控制偏差解耦滑模控制鲁棒性

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稻壳发电残余物稻壳灰对有机物的吸附作用

农业工程学报 2010年第5期26卷 283-287页

作者：谢杰陈天虎庆承松宋浩合肥工业大学资源与环境工程学院合肥230009

为解决稻壳发电残余物——稻壳灰的利用问题,该文研究了稻壳灰在不同条件下对有机污染物的吸附作用。结果表明,稻壳灰在经过碱洗处理后,其对有机污染物的吸附性能明显提高。当溶液pH值小于7.0时,稻壳灰对有机污染物的吸附效果要好于pH... 详细信息

为解决稻壳发电残余物——稻壳灰的利用问题,该文研究了稻壳灰在不同条件下对有机污染物的吸附作用。结果表明,稻壳灰在经过碱洗处理后,其对有机污染物的吸附性能明显提高。当溶液pH值小于7.0时,稻壳灰对有机污染物的吸附效果要好于pH值大于7.0时的吸附效果。该研究表明,稻壳灰经过碱洗处理后,可以用作吸附剂,吸附污水中的有机污染物,实现废物的再次利用。

关键词：稻壳灰处理吸附作用有机污染物

ASAF: altered spontaneous activity fingerprinting in Alzheimer’s disease based on multisite fMRI

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Science Bulletin 2019年第14期64卷 998-1010页

作者： Jiachen Li Dan Jin Ang Li Bing Liu Chengyuan song Pan Wang Dawei Wang Kaibin Xu Hongwei Yang Hongxiang Yao Bo Zhou Alexandre Bejanin Gael Chetelat Tong Han Jie Lu qing Wang Chunshui Yu Xinqing Zhang Yuying Zhou Xi Zhang Tianzi Jiang Yong Liu Ying Han Department of Neurology Xuanwu Hospital of Capital Medical University Beijing 100053 China Department of Radiology Chinese PLA General Hospital Beijing 100853 China Université Normandie Inserm Université de Caen-Normandie Inserm UMR-S U1237 GIP Cyceron Caen 14000 France Department of Radiology Tianjin Huanhu Hospital Tianjin 300350 China Department of Radiology Tianjin Medical University General Hospital Tianjin 300052 China Center of Alzheimer's Disease Beijing Institute for Brain Disorders Beijing 100053 China Beijing Institute of Geriatrics Beijing 100053 China National Clinical Research Center for Geriatric Disorders Beijing 100053 China Brainnetome Center & National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100190 China School of Artificial Intelligence University of Chinese Academy of Sciences Beijing 100049 China Center for Excellence in Brain Science and Intelligence Technology Institute of Automation Chinese Academy of Sciences Beijing 100190 China Department of Neurology Qilu Hospital of Shandong University Ji'nan 250012 China Department of Neurology Tianjin Huanhu Hospital Tianjin 300350 China Institute of Geriatrics and Gerontology Chinese PLA General Hospital Beijing 100853 China Department of Radiology Qilu Hospital Ji'nan 250012 China Department of Radiology Xuanwu Hospital of Capital Medical University Beijing 100053 China

Several monocentric studies have noted alterations in spontaneous brain activity in Alzheimer's disease (AD), although there is no consensus on the altered amplitude of low-frequency fluctuations in AD patients. The main aim of the present study was to identify a reliable and reproducible abnormal brain activity pattern in AD. The amplitude of local brain activity (AM), which can provide fast mapping of spontaneous brain activity across the whole brain, was evaluated based on multisite rs-fMRI data for 688 subjects (215 normal controls (NCs), 221 amnestic mild cognitive impairment (aMCI) 252 AD). Two-sample t-tests were used to detect group differences between AD patients and NCs from the same site. Differences in the AM maps were statistically analyzed via the Stouffer's meta-analysis. Consistent regions of lower spontaneous brain activity in the default mode network and increased activity in the bilateral hippocampus/parahippocampus, thalamus, caudate nucleus, orbital part of the middle frontal gyrus and left fusiform were observed in the AD patients compared with those in NCs. Significant correlations (P?

关键词： Brain spontaneous activity Multisite Biomarkers Leave-one-site-out cross-validation Alzheimer's disease

Quick determination of gas pressure before uncovering coal in cross-cuts and shafts

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Journal of China University of Mining and Technology 2008年第4期18卷 494-499页

作者： JIANG Cheng-lin WANG Chen LI Xiao-wei CHEN Yu-jia XIE qing-xue LIU Ying TANG Jun YANG Fei-long WANG Fa-kai DENG Su-hua ZHANG Chao-jie CHENG song-li LV Shu-wen School of Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The determination of gas pressure before uncovering coal in cross-cuts and in shafts is one of the important steps in pre- dicting coal and gas outbursts. However, the time spent for testing gas pressure is, at present, very long, seriously affecting the ap- plication of outburst prediction techniques in opening coal seams in cross-cuts and shafts. In order to reduce the time needed in gas pressure tests and to improve the accuracy of tests, we analyzed the process of gas pressure tests and examined the effect of the length of boreholes in coal seams in tests. The result shows that 1) the shorter the borehole, the easier the real pressure value of gas can be obtained and 2) the main factors affecting the time spent in gas pressure tests are the length of the borehole in coal seams, the gas emission time after the borehole has been formed and the quality of the borehole-sealing. The longer the length of the bore- hole, the longer the gas emission time and the larger the pressure-relief circle formed around the borehole, the longer the time needed for pressure tests. By controlling the length of the borehole in a test case in the Huainan mining area, and adopting a quick sealing technique using a sticky liquid method, the sealing quality was clearly improved and the gas emission time as well as the amount of gas discharged greatly decreased. Before the method described, the time required for the gas pressure to increase during the pressure test process, was more than 10 days. With our new method the required time is only 5 hours. In addition, the accuracy of the gas pressure test is greatly improved.

关键词： gas pressure sticky liquid sealing quick test cross-cut shaft

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成像卫星在轨智能处理技术研究进展

宇航学报 2022年第3期43卷 259-270页

作者：王兆魁方青云韩大鹏清华大学航天航空学院北京100084

从成像卫星在轨智能处理技术的重要性出发,分析了现阶段国内外研究现状,并总结了星上计算资源受限、实时性要求高、缺少大规模数据集、空间环境特殊性等在轨智能面临的主要挑战。针对问题,系统总结了智能算法、硬件平台和优化技术三个... 详细信息

从成像卫星在轨智能处理技术的重要性出发,分析了现阶段国内外研究现状,并总结了星上计算资源受限、实时性要求高、缺少大规模数据集、空间环境特殊性等在轨智能面临的主要挑战。针对问题,系统总结了智能算法、硬件平台和优化技术三个方面的相关技术,其中对于遥感目标智能检测算法,详细描述了数据集、模型架构、实时性等多个方面。最后,对成像卫星在轨智能处理技术未来发展进行了展望。

关键词：人工智能在轨实现优化技术目标检测

过滤体结构对柴油机微粒捕集器加热再生过程影响的数值研究

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中南大学学报（自然科学版） 2007年第2期38卷 314-319页

作者：刘云卿龚金科鄂加强湖南大学机械与汽车工程学院湖南长沙410082

针对车用柴油机微粒捕集器过滤体孔道内的加热再生模型,采用数值模拟方法,对加热再生过程中过滤体孔道内微粒燃烧与壁面温度沿轴向分布以及过滤体结构参数对再生过程的影响规律进行数值研究。结果表明:过滤体的壁面温度从过滤体前端向... 详细信息

针对车用柴油机微粒捕集器过滤体孔道内的加热再生模型,采用数值模拟方法,对加热再生过程中过滤体孔道内微粒燃烧与壁面温度沿轴向分布以及过滤体结构参数对再生过程的影响规律进行数值研究。结果表明:过滤体的壁面温度从过滤体前端向后端依次升高,且整个过滤体的峰值温度出现在过滤体后端;较小的过滤体壁面厚度会增加过滤体前端的再生时间,缩短后端的再生时间;较小的过滤体长度及较大的过滤体孔道宽度都可使整个过滤体的再生时间缩短。研究结果可为微粒捕集器再生过程的优化提供重要的理论指导。

关键词：微粒捕集器加热再生过滤体结构数值模拟

Open metallocene——VIII. Electronic structure of PD_2ML compounds

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Acta Chimica Sinica English Edition 1989年第4期7卷 333-341页

作者： ZHANG yun-Hong LIU Ju-Zheng LIANG Ying-Qiu TANG Ao-qing Institute of Theoretical Chemistry Jilin UniversityChangchun

EHMO method has been used to calculate the electronic structure of PD_2ML compounds (PD-pentadienyl or methyl-substituted one, M-transition metal atom, L-Lewis base). Compared with CP_2M (CP-cyclopentadienyl), fragment orbitals of PD_2M serve as starting point for general account of the effects of forming M-L bonds on configuration, conformation and stability of PD_2- ML compounds.

关键词： VIII Open metallocene Electronic structure of PD2ML compounds PD

全球价值链的深度嵌入与技术进步关系的机理与测算

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经济纵横 2019年第12期 74-85页

作者：宋宪萍贾芸菲北京理工大学人文与社会科学学院

在深度嵌入全球价值链过程中,需要重新思考国际分工格局,对全球价值链的技术进步效果进行重新审视。研究发现,初步嵌入全球价值链的发展中国家努力与跨国公司的要求相匹配,在此条件下实现的技术进步只是一种"幻像"。一旦代工企业有可能... 详细信息

在深度嵌入全球价值链过程中,需要重新思考国际分工格局,对全球价值链的技术进步效果进行重新审视。研究发现,初步嵌入全球价值链的发展中国家努力与跨国公司的要求相匹配,在此条件下实现的技术进步只是一种"幻像"。一旦代工企业有可能更进一步攀升到价值链高端时,就会触及发达国家跨国公司的利益,形成"技术进步悖论"。在非对称的贸易模式下,全球价值链实质上仍然是一个有中心和外围、主导和依附关系的国际劳动分工体系,技术创新的"锁定效应"和分工固化风险更加突出。运用投入产出分析法,利用2007-2016年我国23个工业行业面板数据进行实证分析后发现,多个行业的全球价值链嵌入程度与技术进步呈倒U型关系。因此,需要彻底转变经济增长模式,构建国家创新链。

关键词：全球价值链技术进步隐性变量法估算投入产出表