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Nanoencapsulation of hexavalent chromium with nanoscale zero-valent iron:High resolution chemical mapping of the passivation layer

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Journal of Environmental Sciences 2018年第5期30卷 4-13页

作者： Xiao-yue Huang lan ling Wei-xian Zhang State Key Laboratory for Pollution Control College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Solid phase reactions of Cr（Ⅵ） with Fe（0） were investigated with spherical-aberration-corrected scanning transmission electron microscopy（Cs-STEM） integrated with X-ray energy-dispersive spectroscopy（XEDS）. Near-atomic resolution elemental mappings of Cr（Ⅵ）–Fe（0） reactions were acquired. Experimental results show that rate and extent of Cr（Ⅵ） encapsulation are strongly dependent on the initial concentration of Cr（Ⅵ） in solution. Low Cr loading in nZⅥ（〈1.0 wt%） promotes the electrochemical oxidation and continuous corrosion of n ZⅥ while high Cr loading（〉1.0 wt%） can quickly shut down the Cr uptake. With the progress of iron oxidation and dissolution, elements of Cr and O counter-diffuse into the nanoparticles and accumulate in the core region at low levels of Cr（Ⅵ）（e.g., 〈 10 mg/L）. Whereas the reacted n ZⅥ is quickly coated with a newly-formed layer of 2–4 nm in the presence of concentrated Cr（Ⅵ）（e.g., 〉 100 mg/L）. The passivation structure is stable over a wide range of pH unless pH is low enough to dissolve the passivation layer. X-ray photoelectron spectroscopy（XPS） depth profiling reconfirms that the composition of the newly-formed surface layer consists of Fe（Ⅲ）–Cr（Ⅲ）（oxy）hydroxides with Cr（Ⅵ） adsorbed on the outside surface. The insoluble and insulating Fe（Ⅲ）–Cr（Ⅲ）（oxy）hydroxide layer can completely cover the n ZⅥ surface above the critical Cr loading and shield the electron transfer. Thus, the fast passivation of nZⅥ in high Cr（Ⅵ） solution is detrimental to the performance of nZⅥ for Cr（Ⅵ） treatment and remediation.

关键词： Nanoscale zero-valent iron (nZVI) Hexavalent chromium Solid phase reaction Passivation Spherical-aberration-correctedscanning transmission electronmicroscopy (Cs-STEM)

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Asymmetric polymerase chain reaction and loop-mediated isothermal amplification(AP-LAMP) for ultrasensitive detection of microRNAs

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Chinese Chemical Letters 2020年第1期31卷 159-162页

作者： Ruili Wang ling lan Li Liu Liang Cheng Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Centre for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

In this manuscript,we first report an ultrasensitive detection assay of microRNA by combing asymmetric polymerase chain reaction(A-PCR)and loop-mediated isothermal amplification(LAMP)*** A-PCR obtained an extended single strand to form LAMP stem-loop structure under isothermal amplification *** used miRNAs as a loop primer probe in LAMP reaction and completed its ultrasensitive and rapid *** established method furnished a fast,specific and efficient detection of target miRNA with a detection limit as low as 10 amol/L in 90 min.

关键词： microRNA LAMP Asymmetric PCR Ultrasensitive detection Rapid detection

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Synthesis of Ni_2P promoted trimetallic NiMoW/γ-Al_2O_3 catalysts for diesel oil hydrotreatment

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Journal of Natural Gas Chemistry 2011年第2期20卷 117-122页

作者： ling lan Shaohui Ge Kunhong Liu Yuandong Hou Xiaojun Bao College of Chemical Engineering China University of Petroleum Beijing 102249 China Petrochemical Research Institute PetroChina Company Limited Beijing 100195 China

The Ni2P promoted and γ-Al2O3 supported NiMoW sulfide catalyst consisting of 4 wt% Mo, 22 wt% W, 2 wt% Ni and 2.5 wt% Ni2P was synthesized by a co-impregnation method. The catalysts were characterized by N2 adsorption-desorption, X-ray diffraction （XRD）, diffuse reflectance infrared Fourier transform （DRIFT） spectroscopy, NH3 temperature-programmed desorption （NH3-TPD） and transmission electron microscopy （TEM）. The results showed that Ni2P, Ni, Mo and W species were highly dispersed over γ-Al2O3. The hydrodesulfurization （HDS） of dibenzothiophene （DBT） showed that the presence of Ni2P brought a strong promotional effect on the HDS activity, which was further confirmed by the HDS and hydrodenitrogenation （HDN） of diesel oil under industrial conditions. The enhancement in HDN activity and stability by Ni2P addition could be attributed more to the effect of new active sites of Ni2P than that of acidity modification. The as-prepared Ni2P-NiMoW/γ-Al2O3 catalyst showed better hydrotreating performance than NiMoW/γ-Al2O3 and commercial catalysts.

关键词： NiMoW sulfide Ni2P phosphide hydrodesulfurization hydrodenitrogenation diesel oil

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One-step modification method of a superhydrophobic surface for excellent antibacterial capability

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Friction 2023年第4期11卷 524-537页

作者： ling lan Yue-lan DI Hai-dou WANG Yan-fei HUANG Li-na ZHU Xu-hang LI School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China National Key Laboratory for Remanufacturing Academy of Army Armored ForcesBeijing 100072China National Engineering Research Center for Remanufacturing Army Academy of Armored ForcesBeijing 100072China

In this study,micro/nanostructures are fabricated on the surface of 3Cr13 stainless steel via laser etching,and a superhydrophobic coating with silver nanoparticles(AgNPs)is prepared by utilizing the reduction–adsorption properties of polydopamine(PDA).We investigate the effect of soaking time from the“one-step method”on the reduction of nano-Ag,surface wettability,and antibacterial *** electron microscopy is performed to analyze the distribution of nano-Ag on the surface,whereas X-ray energy dispersive spectroscopy and X-ray photoelectron spectroscopy are used to analyze the crystal structures and chemical compositions of different *** deposited with PDA on their surface are soaked in a 1H,1H,2H,2H-perfluorodecyltriethoxysilane water–alcohol solution containing AgNO3 for 3 ***,a“one-step method”is used to prepare low-adhesion superhydrophobic surfaces containing *** immersion progresses,more AgNPs are deposited onto the *** with the polished surface,the samples prepared via the“one-step method”show significant antibacterial properties against both gram-negative Escherichia coli and gram-positive Staphylococcus *** antibacterial properties of the surface improve as immersion progresses.

关键词： laser etching one-step modification polydopamine(PDA)processing silver nanoparticles(AgNPs) antibacterial superhydrophobic coating

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Global Production Network and the Upgrading of China's Integrated Circuit Industry

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China & World Economy 2010年第6期18卷 109-126页

作者： ling Chen lan Xue Assistant Professor School of Public Policy and Management Tsinghua University Beijing China

Using an analytical framework of the global production network （GPN）, the present paper examines the external environment and the internal dynamics of China＇s integrated circuit （IC） industry. We analyze the transition of China＇s IC industry from a state-led integrated device manufacturers＇ model to deeper integration into the GPN. We also explore the technological sources, the upgrading dynamics as well as the positioning of different nodes of China＇s IC industry in the GPN. We conclude that the ＂East Asia model＇＂ of gradual industrial upgrading might not apply anymore in the new era of GPN. High-technology industries can now be upgraded based on a parallel evolution model. Policy implications for China＇s high-technology industrial upgrading strategies are drawn from our analysis.

关键词： global production network industrial value chain integrated circuit industry

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STABILITY ANALYSIS OF FINITE ELEMENT METHODS FORTHE ACOUSTIC WAVE EQUATION WITH ABSORBINGBOUNDARY CONDITIONS (PART I)

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Journal of Computational Mathematics 1999年第3期17卷 293-306页

作者： Xiu-min Shao Zhi-ling lan(Institute of Mathematics, Academy of Sciences, Beijing 100080, China) 中科院数学所北京

In Part I and Part II of this paper initial-boundary value problems of the acoustic wave equation with absorbing boundary conditions are considered. Their finite element-finite difference computational schemes are proposed. The stability of the schemes is discussed and the corresponding stability conditions are given. Part I and Part II concern the first- and the second-order absorbing boundary conditions, respectively. Finally, numerical results are presented in Part II to show the correctness of theoretical analysis. (Author abstract) 7 Refs.

关键词： stability finite element methods wave equation absorbing boundary conditions

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Photo-triggered Intramolecular Radical Tandem Regioselective Alkylation/Cyclization of 1,6-Dienes with Redox-Active Esters Enabled by an EDA Complex

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Chinese Journal of Chemistry 2023年第1期41卷 37-42页

作者： Bin Sun lan ling Xiaohui Zhuang Lulu Yang Jieli Yin Can Jin Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals Zhejiang University of TechnologyHangzhouZhejiang 310014China College of Pharmaceutical Sciences Zhejiang University of TechnologyHangzhouZhejiang 310014China

A photocatalyst-and metal-free radical tandem alkylation/cyclization between 1,6-dienes and redox-active esters has been devel-oped,affording a series of N-aryl pyrrolidine-2-ones in moderate to good *** transformation is driven by the formation of an electron-donor-acceptor(EDA)complex and a subsequent single electron transfer(SET)*** photocatalyst-free protocol features excellent regioselectivity,mild conditions and broad substrate scope,providing a facile access to 3-alkyl-3,4-dimethyl-1-phe-nylpyrrolidin-2-one.

关键词： Alkylation Cyclization EDA Complex Pyrrolidone Photocatalysis

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Critical emancipatory reflection on a practice-based issue in relation to the working relationship between doctors and nurses in China

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Frontiers of Nursing 2019年第1期6卷 5-11页

作者： Dong-lan ling Hong-Jing Yu Department of Urologic Surgery The Second Affiliated Hospital of Guangzhou Medical University Department of Nursing Administration The Second Affiliated Hospital of Guangzhou Medical University

Objective: Reflection is viewed as the most significant skill and should be advocated for lifelong learning. In order to grasp the process of reflection and embrace the reflective skill, one of the authors of this paper reflects on a practice-based issue in relation to the communication between doctors and nurses, to gain new understanding and thus improve the authors' clinical ***: Smyth's framework with four stages is utilized as an ideal framework to guide the author's reflection on the practice-based issue to free the author from her entrenched assumptions and the oppressive forces that limit her ***: The espoused and enacted theory, together with the critical reflection theory, are used to explore the values and beliefs that essentially govern the author's practice and how these are distinct from the author's worldviews. Following this, critical emancipatory reflection is undertaken to explore the dominant power structures within the author's workplace. Furthermore, given the hegemonic and chaotic working context of this issue, hegemony and symbolic interaction theory are applied to unearth the various hidden constraining and oppressive forces. Additionally, socialization theory is utilized to help the author achieve professional ***: Reconstructing the practice-based issue empowers the author to realize that in the future, she should act as a reflective practitioner, creating a daily habit, staying alert to practice, seeing things freshly, finding support systems, improving communication skills, conducting reflective research, and reifying reflective practice. Ultimately, the author will be sufficiently equipped to be able to transform her practice and change its outcomes.

关键词： reflective skill critical emancipatory reflection Smyth’s framework hegemony socialization theory transformative practice

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Government Innovations in Building Harmonious Society

Government Innovations in Building Harmonious Society

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2006 International Conference on Public Administration

作者： ling lan HUO Ying-yi Tianjin University of Finance & Economics

ISBN: (纸本)7811142686

The paper first reviews the theory and practice on government innovation around the world, drawing valuable experiences from Osborne and Gaebler’s ten principles of "reinventing government" for china to learn. Then reviews the practices of China’s government innovations since it adopted policies of market-oriented economic reform and open-up to outside world, identifies the difference from those of full-blown market system. Thereby, analyzes special problems exist in China present society which impede the process of building a harmonious society. Finally the paper highlights important government innovations needed for a harmonious society, these are: responsible and responsive, effective and efficient, open and transparent, as well as digital and professional government.

关键词： Government Innovation Building Harmonious Society Good Governance

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Transplantation of bone marrow-derived endothelial progenitor cells and hepatocyte stem cells from liver fibrosis rats ameliorates liver fibrosis

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World Journal of Gastroenterology 2018年第2期24卷 237-247页

作者： ling lan Ran Liu ling-Yun Qin Peng Cheng Bo-Wei Liu Bing-Yong Zhang Song-Ze Ding Xiu-ling Li Department of Gastroenterology and Hepatology the People's Hospital of Zhengzhou University(the Henan Provincial People’s Hospital) Department of Oncology Henan Provincial Rongjun Hospital Department of Gastroenterology and Hepatology the Children’s Hospital of Zhengzhou Intensive Care Unit the Second Affiliated Hospitalof Luohe Medical College

AIM To explore the effectiveness for treating liver fibrosisby combined transplantation of bone marrow-derived endothelial progenitor cells(BM-EPCs) and bone marrow-derived hepatocyte stem cells(BDHSCs) from the liver fibrosis *** The liver fibrosis rat models were induced with carbon tetrachloride injections for 6 wk. BM-EPCs from rats with liver fibrosis were obtained by different rates of adherence and culture induction. BDHSCs from rats with liver fibrosis were isolated by magnetic bead cell sorting. Tracing analysis was conducted by labeling EPCs with PKH26 in vitro to show EPC location in the liver. Finally, BM-EPCs and/or BDHSCs transplantation into rats with liver fibrosis were performed to evaluate the effectiveness of BM-EPCs and/or BDHSCs on liver *** Normal functional BM-EPCs from liver fibrosis rats were successfully obtained. The co-expression level of CD133 and VEGFR2 was 63.9% ± 2.15%. Transplanted BM-EPCs were located primarily in/near hepatic sinusoids. The combined transplantation of BM-EPCs and BDHSCs promoted hepatic neovascularization, liver regeneration and liver function, and decreased collagen formation and liver fibrosis degree. The VEGF levels were increased in the BM-EPCs(707.10 ± 54.32) and BM-EPCs/BDHSCs group(615.42 ± 42.96), compared with those in the model group and BDHSCs group(P lantation induced maximal up-regulation of PCNA protein and HGF m RNA levels. The levels of alanine aminotransferase(AST), aspartate aminotransferase, total bilirubin(TBIL), prothrombin time(PT) and activated partial thromboplastin time in the BMEPCs/BDHSCs group were significantly improved, to be equivalent to normal levels(P > 0.05) compared with those in the BDHSC(AST, TBIL and PT, P lantation of BM-EPCs/BDHSCs combination significantly reduced the degree of liver fibrosis(staging score of 1.75 ± 0.25 vs BDHSCs 2.88 ± 0.23 or

关键词： Bone marrow Endothelial progenitor cells Liver stem cell Cell transplantation Liver fibrosis

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