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Effects of urban grass coverage on rainfall-induced runoff in Xi'an loess region in China

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Water Science and Engineering 2017年第4期10卷 320-325页

作者： Jing Li, Zhan-bin Li Meng-jing Guo Peng Li sheng-dong cheng State Key Laboratory Base of Eco-Hydraulic Engineering in Arid Areas Xi'an University of TechnologyXi'an 710048China

In this study, laboratory rainfall simulation experiments were conducted to investigate the regulatory effects of grass coverage on rainfallrunoff processes. A total of 80 grass blocks planted with well-grown manilagrass, together with their root systems, were sampled from an eastern suburban area of Xi'an City in the northwest arid area of China and sent to a laboratory for rainfall simulation experiments. The runoff and infiltration processes of a slope with different grass coverage ratios and vegetation patterns were analyzed. The results show that the runoff coefficient decreases with the increase of the grass coverage ratio, and the influence of grass coverage on the reduction of runoff shows a high degree of spatial variation. At a constant grass coverage ratio, as the area of grass coverage moves downward, the runoff coefficient, total runoff,and flood peak discharge gradually decrease, and the flood peak occurs later. With the increase of the grass coverage ratio, the flood peak discharge gradually decreases, and the flood peak occurs later as well. In conclusion, a high grass coverage ratio with the area of grass coverage located at the lower part of the slope will lead to satisfactory regulatory effects on rainfall-induced runoff.

关键词： Rainfall simulation Urban vegetation in arid area Rainfall-runoff process Regulatory effect Xi'an loess region

Convenient synthesis of chiral H_4-BINOL via direct hydrogenation of BINOL

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Chinese Chemical Letters 2010年第11期21卷 1277-1280页

作者： Qian Chang Ding Yun Feng Du Xin sheng Li dong cheng Xu Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 China

A simple,highly effective hydrogenation of chiral BINOL to provide H_4-BINOL in multigram scale with good yield（up to 78% yield） was developed.A series of heterogeneous catalysts was tested in the hydrogenation;;the best result was obtained with 5%Pd/ C in EtOH under the H_2 pressure of 50 bar for 2 *** method is a more useful method for practical synthesis of optically pure H4- BINOL than other available methods.

关键词： Hydrogenation 1 1'-Bi-2-naphthol 5 6 7 8-Tetrahydro-1 1'-bi-2-naphthol Chiral Pd/C

Development of A Series NV-F Grade Extra High Strength Plate Steels for Offshore Structure and Shipbuilding

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Journal of Iron and Steel Research International 2011年第S1期18卷 971-977页

作者： LIU dong-sheng,cheng Bing-gui [Institute of Research of Iron and Steel (IRIS),Shasteel Jinfeng Town,Zhangjiagang 215625,Jiangsu,China ] IRIS Zhangjiagang 215625 Jiangsu Peoples R China

Systematic research on developing a series of extra high strength steel plates for shipbuilding via thermomechanical control process (TMCP) is introduced.A microalloyed low carbon-equivalent SiMnCrNiCu steel was used to develop F460 *** low carbon Cu-Ni containing steels were used to develop NV-F550,NV-F620 and NV-F690 steel *** effect of TMCP parameters on microstructure and properties was investigated by test-scale plant *** production trials were conducted to verify the validity of the laboratory studies on the F460 *** plates in 45-60 mm thickness met Det Norske Veritas NV-F460 *** effect of heat-input on the mechanical properties of the coarse-grained-heat-affect-zone (CGHAZ) of the advanced heavy plates was studied.

关键词： TMCP heavy plate steels high strength-toughness

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基于改进APIT的移动机器人动态定位

北京邮电大学学报 2016年第5期39卷 67-71,88页

作者：冯晟吴成东张云洲东北大学信息科学与工程学院沈阳110819

针对室内无线传感器网络通信传输不稳定和定位精度较差的情况,提出了一种移动机器人自主动态定位系统,通过实时选择邻近信标节点,确定节点坐标构成的边界,绘制局部网格空间,实现机器人动态定位.利用接收信号强度指标实现测距,然后采用... 详细信息

针对室内无线传感器网络通信传输不稳定和定位精度较差的情况,提出了一种移动机器人自主动态定位系统,通过实时选择邻近信标节点,确定节点坐标构成的边界,绘制局部网格空间,实现机器人动态定位.利用接收信号强度指标实现测距,然后采用基于测距的改进近似三角形内点测试(APIT)算法完成定位,再使用卡尔曼算法修正定位误差.该方法适用于室内网络传输不稳定的实际情况,采用卡尔曼滤波器获得最优数据.实验结果表明,该移动机器人自主动态定位方法比基于网格的极大似然方法具有更好的精度和适应性.

关键词：无线传感器网络动态定位卡尔曼滤波算法接收信号强度指标

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用于场景分类的显著建筑物区域检测

上海交通大学学报 2011年第8期45卷 1130-1135页

作者：陈硕于晓升吴成东陈东岳东北大学信息科学与工程学院沈阳110819

为了实现城市区域内室外场景的快速分类,提出了一种基于视觉注意力选择机制的显著建筑物区域检测方法.该方法首先通过Gabor算子对图像进行滤波,得到水平方向与垂直方向的联合增强图像,然后利用基于相位傅里叶变换(Phase Fourier Transfo... 详细信息

为了实现城市区域内室外场景的快速分类,提出了一种基于视觉注意力选择机制的显著建筑物区域检测方法.该方法首先通过Gabor算子对图像进行滤波,得到水平方向与垂直方向的联合增强图像,然后利用基于相位傅里叶变换(Phase Fourier Transform,PFT)的显著性映射算法提取视野中的显著建筑物候选区域,最后通过方向直方图判别算法去除干扰目标,并采用CV(Chan-Vese)模型实现显著建筑物区域的分割.该方法在注意力选择机制及建筑物方向特征的基础上,提取具有场景代表性的建筑物区域信息,增强了算法的时效性和场景分析能力,同时实现了区域信息在像素级上的精确检测,并将其应用于美国南加州大学的多类室外场景数据库.实验结果表明,显著建筑物区域检测方法在检测结果、计算速度和鲁棒性等方面均取得了较为满意的效果.

关键词：显著性映射区域检测 CV模型 Gabor算子

Efficient Kinetic Resolution of Racemic 3-Nitro-2H-Chromene Derivatives Catalyzed by Takemoto’s Organocatalyst

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Efficient Kinetic Resolution of Racemic 3-Nitro-2H-Chromene ...

Organocatalytic One-Pot Tandem Reaction for the Synthesis of Optically Active 2-Amino-2-Chromene Derivatives

中国化学会第27届学术年会

作者： Li-Ping Fan, Xin-sheng Li, dong-cheng Xu, Jian-Wu Xie* Department of Chemistry and Life Science, Zhejiang Normal University, Jinhua, 321004

＜正＞The 3-nitro-2H-chromene is very important unit which is recognized due to their biological activity and their importance as precursors of flavonols, amines, and other important targets.

关键词： kinetic resolution chromenes organocatalyst

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Organocatalytic One-Pot Tandem Reaction for the Synthesis of...

中国化学会第27届学术年会

作者： Li-Ping Fan, Xin-sheng Li, dong-cheng Xu, Jian-Wu Xie* Department of Chemistry and Life Science, Zhejiang Normal University, Jinhua,321004

＜正＞Chromene derivatives are an important class of heterocycles, widely present in plants, including edible vegetables and fruits. And they are of considerable interest as they possess a wide range

关键词： 2-amino-2-chromene One-Pot Tandem Reaction Michael addition

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粉煤灰中残碳的特性和利用

粉煤灰综合利用 2005年第1期19卷 3-5页

作者：盛昌栋张军东南大学动力系南京210096

介绍了粉煤灰中残碳和富碳颗粒的特性和分离技术, 论述了残碳特性对颗粒分离和利用的影响, 分析了残碳的利用途径和前景。

关键词：粉煤灰残碳综合利用富碳颗粒分离技术

Magnetron sputtered nickel oxide with suppressed interfacial defect states for efficient inverted perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 348-355页

作者： Guoqiang Ma Qin Tan Zhaoning Li Jingwei Xiu Jiafeng Wang Tianle cheng dong He Qiang Sun Xuhang Ma Francesco Lamberti Zhubing He Department of Materials Science and Engineering Institute of Innovative Materials (I2M) Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation (FSSEG)Southern University of Science and Technology (SUSTech) Core Research Facilities Southern University of Science and Technology Department of Chemical Sciences Department of Industrial Engineering University of Padova

Widely used spin-coated nickle oxide （NiOx） based perovskite solar cells often suffer from severe interfacial reactions between the NiOxand adjacent perovskite layers due to surface defect states,which inherently impair device performance in a long-term view,even with surface molecule *** this study,we developed high-quality magnetron-sputtered NiOxthin films through detailed process optimization,and compared systematically sputtered and spin-coated NiOxthin film surfaces from materials to *** sputtered NiOxfilms exhibit improved crystallinity,smoother surfaces,and significantly reduced Ni3+or Ni vacancies compared to their spin-coated ***,the interface between the perovskite and sputtered NiOxfilm shows a substantially reduced density of defect *** solar cells （PSCs） fabricated with our optimally sputtered NiOxfilms achieved a high power conversion efficiency （PCE） of up to 19.93%and demonstrated enhanced stability,maintaining 86.2% efficiency during 500 h of maximum power point tracking under one standard sun ***,with the surface modification using (4-(2,7-dibromo-9,9-dimethylacridin-10（9H）-yl)butyl)p hosphonic acid （DMAcPA）,the device PCE was further promoted to 23.07%,which is the highest value reported for sputtered NiOxbased PSCs so far.

关键词： Nickle oxide Magnetron sputter Defect Stability Perovskite solar cell