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Synergic Mechanism of an Organic Corrosion Inhibitor for Preventing Carbon Steel Corrosion in Chloride Solution

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Journal of Wuhan University of Technology(Materials Science) 2015年第2期30卷 325-330页

作者：刘志勇 YU Lei li qingzhong School of Civil Engineering Yantai University School of Chemistry and Chemical Engineering Yantai University

The inhibition effect of dimethylethanolamine（DMEA） and its composite with carboxylic acid was studied with the electrochemical tests. The experimental results indicate that DMEA is not a good inhibitor but the composite of DMEA with caprylic acid exhibits excellent inhibiting efficiency. The synergic mechanism of the organic corrosion inhibitors（OCIs） was studied with quantum chemical calculations. It is found that the DMEA forms a quaternary ammonium salt with the proton in carboxylic acid, and a cyclic complex formed between the salt and Fe may be responsible for the enhancement of inhibiting efficiency. The possible hydrogen bond formed between DMEA and carboxylic acid is not enough for the inhibiting effect. This work is helpful to proposing theoretical interpretation as well as developing a functional organic inhibitor to improve the durability of reinforced concrete contaminated with chloride.

关键词： carbon steel organic corrosion inhibitor polarization inhibition chloride solution

Halogen Bond Catalysis on Carbonyl-Olefin Ring-Closing Metathesis Reaction:Comparison with Lewis Acid Catalysis

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Chinese Journal of Chemistry 2022年第11期40卷 1275-1284页

作者： Ying li Yuanyuan Sun lingpeng Meng qingzhong li Yanli Zeng College of Chemistry and Materials Science Hebei Key Laboratory of Inorganic Nano-materialsHebei Normal UniversityShijiazhuangHebei 050024China The Laboratory of Theoretical and Computational Chemistry College of Chemistry&Chemical EngineeringYantai UniversityYantaiShandong 264005China

The carbonyl-olefin ring-closing metathesis reactions have become a powerful tool for carbon-carbon bond *** this work,the halogen bond catalysis and classical Lewis acid catalysis on the carbonyl-olefin ring-closing metathesis reaction were investigated by density function *** both the halogen bond catalysis and classical Lewis acid catalysis,the carbonyl-olefin ring-closing me-tathesis reaction occurs by[2+2]-cycloaddition process and[2+2]-cycloreversion process,the reaction energy barriers are low,there-fore,it can be performed easily at room *** essential difference of the two kinds of catalysts is that the catalytic mecha-nism of halogen bond catalysis is mainly contribution of electrostatic interaction,while that of classical Lewis acid catalysis is mainly catalyzed by orbital *** halogen bond donor catalysts(ICI_(3),IF_(3))are expected to be efficient catalysts for the reaction and further promote the chemical synthesis of carbonyl-olefin ring-closing metathesis reaction.

关键词： Halogen bond donors Lewis acids Electrostatic interactions Orbital interaction Carbonyl-olefin ring-closing metathesis

A Hybrid Territorial Aquatic Bionic Soft Robot with Controllable Transition Capability

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Journal of Bionic Engineering 2023年第2期20卷 568-583页

作者： qingzhong li Fukang Zhang Zeying Jing Fujie Yu Yuan Chen Department of Mechatronics and Information Engineering Shandong University at WeihaiWeihai264209China

In this paper,a bionic mantis shrimp amphibious soft robot based on a dielectric elastomer is proposed to realize highly adaptive underwater multimodal *** the action of an independent actuator,it is not only able to complete forward/backwards motion on land but also has the ability of cyclically controllable transition motion from land to water surface,from water surface to water bottom and from water bottom to *** fastest speed of the soft robot on land is 170 mm/s,and it can crawl while carrying up to 4.6 times its own *** maximum speeds on the water surface and the water bottom are 30 mm/s and 14.4 mm/s,***,the soft robot can climb from the water bottom with a 9°slope transition to *** with other similar soft robots,this soft robot has outstanding advantages,such as agile speed,large load-carrying capacity,strong body flexibility,multiple motion modes and strong underwater ***,nonlinear motion models of land crawling and water swimming are proposed to improve the environmental adaptability under multiple modalities,and the correctness of the theoretical model is verified by experiments.

关键词： Transition Amphibious soft robot Dielectric elastomers Bionic mantis shrimp soft robot

A research study on the spallation strength of LY12 aluminum under the pre-compression condition

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 505-513页

作者： ShiWen Zhang Cangli liu qingzhong li JinSong Hua Qiao liu Inst Fluid Phys Lab Shock Wave & Detonat Phys Res Mianyang 621900 Peoples R China

To pre-compress the disk-shaped LY12 samples along the radial direction can be done with the aid of overstress assembly by heating or by mechanical clamping, which can also generate the deviatoric stress fields under different states. The spallation signals of these pre-compressed samples are measured by VISAR in the light-gas gun shock experiments. The experimental results show that even under the same impact velocity, the pullback amplitudes of the velocity at the free surface of the sam- pies vary significantly. According to the experimental data, we propose a distinct concept that the material spallation strength is closely related to the deviatoric stress fields in the material. Based on the numerical simulation, we develop a damage con- stitutive model, which reveals that the deviatoric stress reduces the tensile threshold of the void growth. The numerical inves- tigations also demonstrate that the spallation strength decreases as pre-compression increases. The experimental idea proposed in this paper can also be used to study the spallation process in other structures.

关键词： LY12 aluminum spallation strength pre-compression spherical spallation

Heterogeneous Network-Based Chronic Disease Progression Mining

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Big Data Mining and Analytics 2019年第1期2卷 25-34页

作者： Chenfei Sun qingzhong li lizhen Cui Hui li Yuliang Shi Research Center of Software and Data Engineering Shandong University

Healthcare insurance fraud has caused billions of dollars in losses in public healthcare funds around the world. In particular, healthcare insurance fraud in chronic diseases is especially rampant. Understanding disease progression can help investigators detect healthcare insurance frauds early on. Existing disease progression methods often ignore complex relations, such as the time-gap and pattern of disease occurrence. They also do not take into account the different medication stages of the same chronic disease, which is of great help when conducting healthcare insurance fraud detection and reducing healthcare costs. In this paper, we propose a heterogeneous network-based chronic disease progression mining method to improve the current understanding on the progression of chronic diseases, including orphan diseases. The method also considers the different medication stages of the same chronic disease. Extensive experiments show that our method can outperform the existing methods by 20% in terms of F-measure.

关键词： disease progression heterogeneous network healthcare insurance fraud

Synergistic effects between anion-π and tetrel bond

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Synergistic effects between anion-π and tetrel bond

Proton Transfer Promoted by Tetrel Bonding

第十三届全国量子化学会议

作者： Huili Xu qingzhong li School of Chemistry and Chemical Engineering Yantai University

Tetrel bond plays an important role in crystal materials,chemical reactions,and biological *** the present study,the complexes X…pyrazine/l,4-dicyanobenzene…TH F/F TO（X = F,Cl,Br;T = C and Si） have been used to study the interplay between the anion-π and σ-tetrel bond or π-tetrel bond interactions in these *** cooperativity effects are observed when the anion-π and σ-tetrel bond orπ-tetrel bond interactions coexist in the same *** interactions exhibit positive cooperative effects,with shorter binding distances,larger interaction energies,and greater electron densities in the ternary *** effects have been theoretically studied in terms of energetic and geometric features of the complexes as well as the charge *** shortening of the tetrel bond distance in the ternary complexes is dependent on the strength of the anion-π interaction and it becomes larger in the order X=F > Cl> *** cooperative energy ranges from-0.96 to-26.68 kcal/mol.

关键词： Anion-π σ-tetrel bond π-tetrel bond Cooperativity

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Proton Transfer Promoted by Tetrel Bonding

第十三届全国量子化学会议

作者： Yuanxin Wei qingzhong li School of Chemistry and Chemical Engineering Yantai University

Malondialdehyde（MDA） mainly exists in the enol form and its cis-isomer is favored in organic solvents,and it is often taken as a model to study intramolecular proton *** can be used to form a tetrel bond with theπ-hole on the T atom of F TO by using the O atom of MDA（Fig.1）.For each type of tetrel bonding,there are two binding modes（1 and 2）,which distinguish from each other in the orientation of F *** H atom of C-H bond in MDA approaches the O atom of F TO in 1 but the F atom of F TO in *** mode of 1 is more stable than that of 2 due to the presence of a CH…O hydrogen bond in the *** strength of intramolecular hydrogen bond in MDA is strengthened or weakened when the π-hole of F TO binds with the O atom of the hydroxyl or aldehyde group in MDA,***,the separation between the H atom of the hydroxyl group and the O atom of the aldehyde group in MDA varies from 1.644 A in the isolated molecule to 0.987? in TB-Si-a-1,which is smaller than the length of O-H bond in MDA（1.002?）.That is,the intramolecular proton transfer occurs from the hydroxyl group to the aldehyde group in the presence of a very strong tetrel bond with the interaction energy larger than 180 kJ/*** the other hand,a π-π structure（c） is obtained when the π-hole on the T atom of F TO approaches the middle carbon atom of MDA,which is like π-π interactions in aromatic systems.

关键词： Intramolecular proton transfer Tetrel bond π-Hole

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基于小波变换的低照度图像自适应增强算法

中国激光 2015年第2期42卷 272-278页

作者：李庆忠刘清中国海洋大学工程学院山东省海洋工程重点实验室山东青岛266100

提出了一种基于小波变换的低照度图像快速、自适应增强算法。将RGB图像转到HSV空间,并对亮度V图像利用离散小波变换(DWT)将图像的高、低频子带分离。在小波变换的低频子带上利用双边滤波对图像的照射光分量进行快速估计与去除,而在高频... 详细信息

提出了一种基于小波变换的低照度图像快速、自适应增强算法。将RGB图像转到HSV空间,并对亮度V图像利用离散小波变换(DWT)将图像的高、低频子带分离。在小波变换的低频子带上利用双边滤波对图像的照射光分量进行快速估计与去除,而在高频子带上利用模糊变换实现边缘、纹理信息的增强与去噪处理。对处理后的V图像,基于提出的直方图目标函数,利用鲍威尔与模拟退火相结合的优化算法,实现了对比度的快速、自适应增强处理。将增强后的V图像与H、S颜色分量合成为清晰化的彩色图像。实验结果表明,该算法能快速、有效实现低照度图像的清晰化处理。

关键词：图像处理低照度图像小波变换双边滤波模糊增强 Retinex理论

基于改进YOLO和迁移学习的水下鱼类目标实时检测

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模式识别与人工智能 2019年第3期32卷 193-203页

作者：李庆忠李宜兵牛炯中国海洋大学工程学院青岛266100

为了实现非限制环境中水下机器人基于视频图像的水下鱼类目标快速检测,提出基于改进YOLO和迁移学习的水下鱼类目标实时检测算法.针对YOLO网络的不足,设计适合水下机器人嵌入式系统计算能力的精简YOLO网络(Underwater-YOLO).利用迁移学... 详细信息

为了实现非限制环境中水下机器人基于视频图像的水下鱼类目标快速检测,提出基于改进YOLO和迁移学习的水下鱼类目标实时检测算法.针对YOLO网络的不足,设计适合水下机器人嵌入式系统计算能力的精简YOLO网络(Underwater-YOLO).利用迁移学习方法训练Underwater-YOLO网络,克服海底鱼类已知样本集有限的限制.利用基于限制对比度自适应直方图均衡化的水下图像增强预处理算法,克服水下图像的降质问题.利用基于帧间图像结构相似度的选择性网络前向计算策略,提高视频帧检测速率.实验表明,文中算法能实现在非限制环境下海底鱼类目标的实时检测.相比YOLO,文中算法对海底鱼类小目标和重叠目标具有更好的检测性能.

关键词：卷积神经网络深度学习鱼类目标检测单级式目标检测算法(YOLO) 迁移学习