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Chemical Research in Chinese Universities 2015年第4期31卷 549-552页

作者： WANG Yi gao Jingyi ZHAO mengdan LI Jiamei Faculty of Chemistry and Chemical Engineering Yunnan Normal University Kunming 650500 P. R. China

Bifunctional Salen-Cu（II） complex catalyzed cross-coupling reactions of aryl halids with imidazoles or phenylboronic acid reagents have been developed as practical methods for C--N and C--C bond formation. The procedure tolerates aryl halides with various functional groups（such as methoxy, acetyl, nitrile, fluoro and nitro groups） and gives the corresponding coupling products in moderate to high yields. The catalyst remained active after fiye successive catalytic runs without loss in performance.

关键词： Salcn-Cu(II) complex Homogenous catalysis Cross-coupling N-Arylation

Removal Arsenic(V)Efficiency and Characteristics Using Modified Basic Oxygen Furnace Slag in Aqueous Solution

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Journal of Resources and Ecology 2022年第3期13卷 537-546页

作者： YANG Liyun gao mengdan LV Yan LI Shaojie YANG Libing LI Shuwu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Department of Metallurgy Graduate School of EngineeringTohoku UniversitySendaiMiyagi 980-8579Japan Metallurgical Technology Institute Central Iron and Steel Research InstituteBeijing 100053China

Basic oxygen furnace(BOF) slag, the solid waste produced in the steelmaking process, is reused in industry, agriculture and environmental treatment. However, as an adsorbent for wastewater, the removal effect of BOF slag on anionic pollutants needs to be improved. In this study, acid and alkali were used to modify BOF slag,and the removal efficiency and mechanism of arsenic(V) with modified BOF slag in solution were studied. The effects of the As(V) initial concentration, solution pH and reaction time on the removal efficiency were determined by batch experiments, and the removal mechanism of As(V) using modified BOF slag was studied by an adsorption kinetic model and isothermal adsorption model and the Fourier transform infrared spectroscopy(FTIR) and X-ray photoelectron spectroscopy(XPS) spectral analysis. The results showed that the slag modified by 15% sulfuric acid had the best removal effect on As(V), while the removal effect of As(V) by alkali-modified slag was not ideal. The removal rate of As(V) by acid-modified slag increased with the increase in the initial concentration, decreased slowly with the increase in pH and reached equilibrium in 180 min. The adsorption kinetic model and isothermal adsorption model of As(V) by acid-modified BOF slag showed that the chemical adsorption was the limiting *** FTIR and XPS analysis results showed that the silicate and ferrite in the acid-modified slag could remove As(V)in the solution by ion exchange to form an arsenate precipitate. Therefore, modified BOF slag can be used as a potential adsorbent for large scale arsenic polluted waterbody to realize the ecological utilization of industrial solid waste.

关键词： modified BOF slag As(V) removal efficiency removal mechanism

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地聚合物在水体中抗侵蚀性的研究进展

功能材料 2021年第12期52卷 12001-12007,12021页

作者：杨丽韫杨双健高梦郸白皓北京科技大学冶金与生态工程学院北京100083

地聚合物是一种新型绿色建筑材料,具备优异的机械强度、耐高温等性能,此外地聚合物其原料来源广泛,可由含有硅铝的工业固体废弃物制得。因此,地聚合物作为绿色建筑材料有性能优异、工艺简单、能耗低、碳排放低等优点,具有广阔的应用前... 详细信息

地聚合物是一种新型绿色建筑材料,具备优异的机械强度、耐高温等性能,此外地聚合物其原料来源广泛,可由含有硅铝的工业固体废弃物制得。因此,地聚合物作为绿色建筑材料有性能优异、工艺简单、能耗低、碳排放低等优点,具有广阔的应用前景。然而,当地聚合物应用于水环境中时,其在水体中的抗侵蚀性能需要进一步综合分析。在综述地聚合物制备工艺和合成机理的基础上,分析了地聚合物的原料和养护方式对其抗侵蚀性的影响,进一步阐述了地聚合物的三维网络结构和抗衡阳离子的耐侵蚀性,最后提出了地聚合物在水体中抗侵蚀性的研究展望。

关键词：地聚合物合成机理抗侵蚀性水环境

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离群点挖掘技术在交通事件检测中的应用

计算机科学与探索 2014年第1期8卷 111-120页

作者：诸彤宇王奇高梦丹北京航空航天大学软件开发环境国家重点实验室北京100191

交通事件的检测与确认是交通事件管理中的首要问题。基于线圈和视频数据的检测方法由于成本高,检测效果不明显,在实际应用中受到限制。提出了一种基于离群点挖掘的交通事件检测算法。该算法通过使用浮动车(floating car data,FCD)技术... 详细信息

交通事件的检测与确认是交通事件管理中的首要问题。基于线圈和视频数据的检测方法由于成本高,检测效果不明显,在实际应用中受到限制。提出了一种基于离群点挖掘的交通事件检测算法。该算法通过使用浮动车(floating car data,FCD)技术得到路况信息,并提取交通事件特征,建立特征向量。算法简单、高效、易于部署。实验结果表明,同模式识别方法相比,该算法具有较高的准确度,能有效区分常规拥堵与交通事件。

关键词：交通事件浮动车特征分析离群检测

Record-high efficiency perovskite LEDs achieved by accelerating radiative recombination

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Science China Materials 2024年第9期67卷 3039-3040页

作者： Feng gao Department of Physics Chemistry and BiologyLinköping UniversityLinköping58183Sweden

Light-emitting diodes(LEDs)have revolutionized the lighting and displays due to their superior energy *** increasing demand for more efficient and brighter thin-film LEDs in flat-panel displays and solid-state lighting applications has driven extensive research into perovskite materials,which show great promise for high brightness and efficiency.

关键词： lighting radiative high

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Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1637-1648页

作者： Guiyun gao Chenghu Wang Ke gao National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China Beijing Engineering Research Center of Earthquake Observation Beijing100085China Key Laboratory of Compound and Chained Natural Hazards Dynamics Ministry of Emergency Management of ChinaBeijing100085China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen518055China

The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor ***,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable *** this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests *** shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo ***,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress *** inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress *** stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)*** results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress *** inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints *** M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole.

关键词： Stress tensor Hydraulic tests on pre-existing fractures Mean stress Stress constraint Hydraulic fracturing

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun gao Yan Peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

STAT1与STAT3在肝细胞癌及肝衰竭发病机制中的作用

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临床肝胆病杂志 2018年第9期34卷 2017-2020页

作者：高梦丹张永宏赵艳首都医科大学附属北京佑安医院临床检验中心北京100069

肝细胞癌(HCC)及肝衰竭为我国常见的肝脏疾病,其发病率及病死率极高,相关研究虽多但具体发病机制仍不详。通过介绍STAT1及STAT3磷酸化蛋白在HCC及肝衰竭发病机制中的多种作用,如:抗病毒防御、急性期反应、肝损伤、修复、炎症、转化等,... 详细信息

肝细胞癌(HCC)及肝衰竭为我国常见的肝脏疾病,其发病率及病死率极高,相关研究虽多但具体发病机制仍不详。通过介绍STAT1及STAT3磷酸化蛋白在HCC及肝衰竭发病机制中的多种作用,如:抗病毒防御、急性期反应、肝损伤、修复、炎症、转化等,了解其在HCC及肝衰竭发病机制中的具体作用,并以其为分子靶标研制相关药物,应用于临床,对于降低患者病死率具有重要意义。

关键词：癌,肝细胞肝功能衰竭 STAT1转录因子 STAT3转录因子综述

On the core entropy of Newton maps

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Science China Mathematics 2024年第1期67卷 77-128页

作者： Yan gao Department of Mathematics Shenzhen UniversityShenzhen 518060China

In this paper,we define the core entropy for postcritically-finite Newton maps and study its continuity within this *** show that the entropy function is not continuous in this family,which is different from the polyn... 详细信息

关键词： core entropy extended Newton graph critical marking polynomial Newton map

Durable poly(binaphthyl-co-p-terphenyl piperidinium)-based anion exchange membranes with dual side chains

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Journal of Energy Chemistry 2024年第2期89卷 324-335,I0008页

作者： Weiting gao Xuelang gao Qiugen Zhang Aimei Zhu Qinglin Liu Department of Chemical&Biochemical Engineering Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryThe College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina Department of Chemistry Pohang University of Science and Technology(POSTECH)Pohang 790-784South Korea

Building well-developed ion-conductive highways is highly desirable for anion exchange membranes(AEMs).Grafting side chain is a highly effective approach for constructing a well-defined phaseseparated morphological structure and forming unblocked ion pathways in AEMs for fast ion *** of side chains can further enhance phase separation due to the superhydrophobic nature of fluorine ***,their electronic effect on the alkaline stability of side chains and membranes is rarely ***,fluorine-containing and fluorine-free side chains are introduced into the polyaromatic backbone in proper configuration to investigate the impact of the fluorine terminal group on the stability of the side chains and membrane *** poly(binaphthyl-co-p-terphenyl piperidinium)AEM(QBNp TP)has the highest molecular weight and most dimensional stability due to its favorable backbone arrangement among ortho-and meta-terphenyl based ***,by introducing both a fluorinated piperidinium side chain and a hexane chain into the p-terphenyl-based backbone,the prepared AEM(QBNp TP-QFC)presents an enhanced conductivity(150.6 m S cm^(-1))and a constrained swelling at 80℃.The electronic effect of fluorinated side chains is contemplated by experiments and *** results demonstrate that the presence of strong electro-withdrawing fluorine groups weakens the electronic cloud of adjacent C atoms,increasing OH^(-)attack on the C atom and improving the stability of piperidinium *** QBNp TP-QFC possesses a robust alkaline stability at 80℃(95.3%conductivity retention after testing in 2 M Na OH for 2160 h).An excellent peak power density of 1.44 W cm^(-2)and a remarkable durability at 80℃(4.5%voltage loss after 100 h)can be observed.

关键词： Anion exchange membranes Backbone structure Fluorinated side chain Alkaline stability