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Rare Metals 2015年第9期34卷 650-656页

作者： chun-ling li Ding Fan Bin Wang State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology

Tungsten inert gas(TIG) arc-assisted laser welding–brazing was used for the butt joining of 5A06 aluminum alloy to the galvanized steel by preset filler powder without groove. The spreading behavior of liquid metal on the back of the galvanized steel at different assisted welding currents was also investigated. The results show that the assisted TIG arc optimizes the interface reaction temperature, enhances the wettability of liquid metal on the steel side, and forms a sound butt joint at an appropriate welding current. A non-uniform intermetallic compound is formed at the interfacial layer, which is composed of Fe2Al5 close to the steel substrate and Fe4Al13 close to the solidified aluminum. The superior tensile strength of joint is indicated when the welding current ranges from 13 to 16 A. The average tensile strength can reach 151 MPa at the welding current of 16 A, and the corresponding fracture belongs to the ductile and brittle hybrid mode.

关键词： Aluminum alloy Steel Welding–brazing Welding curre

Developing single-atom catalyst-based epoxy coating with active nanocatalytic anticorrosion performance in oxygen environment

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Petroleum Science 2023年第5期20卷 3251-3263页

作者： Meng Cheng Yu-Qi liu Hao Jiang Jun-Hao liu chun-ling li Shuang-Qing Sun Song-Qing Hu School of Materials Science and Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Institute of Advanced Materials China University of Petroleum(East China)Qingdao266580ShandongChina

The stimuli-responsive anticorrosion coatings have drawn great attention as a prospective corrosion protection approach due to their smart self-repairing *** contrast to passive protection mechanism based on post-corrosion microenvironmental changes,a unique active protection strategy based on nanocatalytic oxygen depletion is proposed in this work to inhibit the occurrence of *** FeeNeC catalysts with outstanding oxygen reduction reaction(ORR)activity(half-wave potential of 0.89 V)is firstly synthesized through pre-coordination with organosilane precursor to obtain homogeneously distributed active *** this catalyst is introduced into the coating matrix,uniformly distributed FeeNeC not only compensates the defects but plays a crucial role in adsorption and consumption of diffused oxygen in the *** this dual action,the penetration of corrosive medium,especially oxygen,through coating to metal substrate is greatly suppressed,resulting in effective corrosion inhibition and a significant increase in corrosion resistance of the composite coating compared to pure epoxy *** work provides a new perspective and the starting point for the design of high-performance smart coating with active anticorrosion properties.

关键词： Nanocatalytic anticorrosion Pre-constrained metal ions Single-atom FeeNeC Deoxygenation agent Smart coatings

Studies on The Adsorption Capacity for Bilirubin of The Adsorbent Chitosan-β-Cyclodextrin

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Chinese Chemical Letters 2001年第4期12卷 359-362页

作者： Wei liang XU, chun ling FU, Jun li Department of Chemistry, Zhejiang University, Hua jia chi section, Hangzhou 310029 Department of Chemistry Zhejiang University Hua Jia Chi Section Hangzhou 310029 China

The adsorbent crosslinked chitosan-β-cyclodextrin (β-CD) was prepared by the reaction of glutaraldehyde with chitosan and β-cyclodextrin. This type of adsorbent has high adsorption capacity for unconjugated bilirubin. The adsorption capacity was related to the β-CD content of the adsorbent; phosphate buffer concentration; temperature; pH value; ionic strength and the adsorbent beads. The results indicated that the chitosan-β-CD was a good adsorbent for unconjugated bilirubin with high capacity.

关键词： Chitosan-β-CD adsorption bilirubin.

Clinical research on navel application of Shehuang Paste combined with Chinese herbal colon dialysis in treatment of refractory cirrhotic ascites complicated with azotemia

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World Journal of Gastroenterology 2006年第48期12卷 7798-7804页

作者： Guang-Dong Tong Da-Qiao Zhou Jing-Song He Lai Zhang Zhi-Fei Chen chun-ling Xiao li-Sheng Peng Department of Hepatology Shenzhen Hospital of Traditional Chinese MedicineGuangzhou University of TCM Shenzhen 518033 GuangdongProvince China

AIM: To explore the efficacy and mechanism of a novel therapeutic method of traditional Chinese medicine in patients with refractory cirrhotic ascites complicated with azotemia. METHODS: Seventy-five cases of refractory cirrhotic ascites complicated with azotemia were randomly divided into 3 groups: comprehensive treatment (n = 29), simple treatment (n = 24), and control (n = 22). The basic treatment methods were the same in all groups, including liver protecting medicines, diuretics and supportive drugs. The control group underwent only the basic treatment. Shehuang Paste (SHP) was applied to the navels of the two treatment groups once a day for 30 d. Colon dialysis with Chinese herbs was administered to the comprehensive treatment group once every two days. Before and after treatment, we measured abdominal circumference, BUN, Cr, serum Na+, urine Na+/K+, liver function, endotoxin content, NO, and ET-1. Color Doppler ultrasonography was conducted to measure the portal vein blood flow. RESULTS: The total effective rate for ascites was 72.4% in the comprehensive treatment group, 45.8% in the simple treatment, contrasting with 18.2% in the controls. Between the two treatment groups and the controls, there were significant differences in the effective rates (P 0.05).

关键词： Cirrhotic Refractory ascites Azotemia Vasoactive substance

Residual stress and welding distortion of Al/steel butt joint by arc-assisted laser welding-brazing

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Transactions of Nonferrous Metals Society of China 2019年第4期29卷 692-700页

作者： chun-ling li Ding FAN Xiao-quan YU Jian-kang HUANG State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of TechnologyLanzhou 730050China

The *** finite element method(FEM)is used to simulate the thermo-mechanical behavior of Al/steel tungsten inert gas(TIG)arc-assisted laser welding-brazing(A-LWB)butt *** influence of material nonlinearity,geometrical nonlinearity and work hardening on the welding process is studied,and the differences in the welding temperature field,residual stress and welding distortion by A-LWB and by single laser welding-brazing(SLWB)are *** results show that the thermal cycle,residual stress distribution and welding distortion by the numerical simulation are in good agreement with the measured data by experiments,which verifies the effectiveness of *** with the SLWB,A-LWB can make the high-temperature distribution zone of weld in width direction wider,decrease the transverse tensile stress in the weld and reduce the distribution range of longitudinal tensile *** the welding deformation also decreases to some extent.

关键词： arc-assisted laser welding-brazing(A-LWB) Al/steel finite element method(FEM) temperature field residual stress welding distortion

High-resolution Sonographic Measurements of Lower Extremity Bursae in Chinese Healthy Young Men

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Chinese Medical Journal 2016年第3期129卷 309-312页

作者： Yong-Yan Gao Chi-Qiu Wu Wei-Xing liu Lei Zhang chun-ling li Department of Ultrasound The General Hospital of Chinese People's Armed Police Forces Beijing 100039 China Department of Ultrasound The General Hospital of Zhejiang Corps of Chinese People's Armed Police Forces Hangzhou Zhejiang 310054 China

Background： Lower extremity bursae are very vulnerable to injury during strenuous physical *** the imaging characteristics of normal bursae is essential for early diagnosis of morphological ***, we evaluated the normal range of lower extremity bursae in healthy young men using high-resolution ultrasound （HR-US） ***： Bursae in the lower extremities were examined by HR-US in 290 Chinese healthy young men with a median age of 18 years （range, 18-23 years）.The bilateral suprapatellar bursa （SPB）, deep infrapatellar bursa （DIPB）, popliteal bursa （PB）, and retrocalcaneal bursa （RCB） were imaged and measured for ***： The HR-US identification rates of the SPB, DIPB, PB, and RCB were 89.0% （517/580）, 55.0% （319/580）, 29.4% （171/580）, and 49.5% （287/580）, *** the assumption that the bursae were normal in 95% of the study participants, the length and width values at the maximal cross-section of the SPB, DIPB, PB, and RCB were ≤18.00 and 6.09 mm, 8.10 and 2.1 1 mm, 7.67 and 3.93 mm, and 7.82 and 2.04 mm, ***： Using HR-US imaging, we were able to analyze lower extremity bursae with high detection rates in healthy young *** normal ranges of lower extremity bursa dimensions in healthy young men measured by HR-US in this study could be used as reference values for evaluation of bursa abnormalities in the lower extremity.

关键词： Bursa Lower Extremity Ultrasonography

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CVS中基于残差结构特征的块分类重构算法

华南理工大学学报（自然科学版） 2017年第3期45卷 1-10页

作者：杨春玲李文豪华南理工大学电子信息学院广东广州510640

现有最好的视频压缩感知重构算法大都采用"预测-残差重构"策略,可有效利用帧内和帧间的相关性获得较好的性能,但是残差重构均直接采用SPL算法,忽略了残差信号自身的结构特征,限制了性能的进一步提升.针对该问题,文中提出了一种基于预测... 详细信息

现有最好的视频压缩感知重构算法大都采用"预测-残差重构"策略,可有效利用帧内和帧间的相关性获得较好的性能,但是残差重构均直接采用SPL算法,忽略了残差信号自身的结构特征,限制了性能的进一步提升.针对该问题,文中提出了一种基于预测残差结构特征的块分类重构算法,首先利用残差块观测值的平均能量对残差块进行分类,然后对不同类的残差块采用不同的重构算法.仿真实验表明,用于运动较快的视频序列时,文中方案与SPL算法相比可以获得更好的重构质量.

关键词：视频压缩感知残差重构平均能量残差块分类

Ni-catalyzed cross-electrophile alkyl-alkyl coupling reactions

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Science China Chemistry 2025年

作者： li-Xu You Lan Tian chun-ling Guo Shun-Xi li Yu-Cheng liu Yu-Long li Wei Shu College of Chemistry and Environmental Engineering Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan Sichuan University of Science and Engineering Guangming Advanced Research Institute Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology

Introducing saturated carbon-carbon bonds into organic molecules significantly increases the three-dimensional configuration,thus altering the physical and chemical properties as well as the functions of molecules. Transition-metal-catalyzed carboncarbon cross-couplings represent one of the most straightforward, efficient and modular alternatives to build saturation in a single step. However, the efficient construction of alkyl-alkyl bonds remains a formidable challenge due to the precise manipulation of multiple alkyl metallic intermediates as well as associated competitive side reactions and selectivity control. Over the past years, Ni-catalyzed cross-coupling under reductive conditions has gained more and more attention for alkyl-alkyl crosscoupling partially attributing to the low-valent state of metal centers under reducing conditions, which suppresses the competitive β-hydride elimination process, thus facilitating the formation of alkyl-alkyl bonds. In this review, the initiative and progress of Ni-catalyzed cross-electrophile alkyl-alkyl cross-coupling, including the efforts in racemic and enantioselective formation of alkyl-alkyl bonds, have been summarized and discussed. Moreover, the challenges and further opportunities in this area have also been discussed.

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Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-lin li ling Gong Xiang-li Zhong Hong-Jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

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煤焦油的改质研究

燃料化学学报 2002年第4期30卷 322-327页

作者：张怀平吕春祥李开喜刘春林凌立成中国科学院山西煤炭化学研究所煤转化国家重点实验室山西太原030001

以煤焦油为原料 ,通过在 30 0℃空气氧化 1 2 0min～ 480min和在 430℃氮气热缩聚 50min～ 2 70min ,制备了一系列具有相近软化点的煤焦油沥青。原料煤焦油和改质沥青的化学结构通过NMR、FT IR、元素分析、软化点、族组成和偏光光学进... 详细信息

以煤焦油为原料 ,通过在 30 0℃空气氧化 1 2 0min～ 480min和在 430℃氮气热缩聚 50min～ 2 70min ,制备了一系列具有相近软化点的煤焦油沥青。原料煤焦油和改质沥青的化学结构通过NMR、FT IR、元素分析、软化点、族组成和偏光光学进行分析。在 1 6MPa、480℃下将改质煤焦油沥青进行焦化 ,考察了焦收率和光学组织结构变化。结果表明空气氧化和氮气热缩聚可提高煤焦油沥青软化点、甲苯不溶物含量和焦收率 ,与氮气热缩聚沥青相比 ,相近软化点的空气氧化沥青具有较高的焦收率和O C原子比。空气氧化煤焦油沥青成焦后各向异性光学结构单元尺寸随空气氧化时间增加而逐渐减小。

关键词：改质煤焦油空气氧化氮气热缩聚光学组织结构沥青