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Beckner Inequality on Finite-and Infinite-Dimensional Manifolds

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Chinese Annals of Mathematics,Series B 2006年第5期27卷 581-594页

作者： Pingji DENG fengyu WANG School of Mathematical Sciences Beijing Normal University Beijing 100875 China

By using the dimension-free Harnack inequality, the coupling method, and Bakry-Emery＇s argument, some explicit lower bounds are presented for the constant of the Beckner type inequality on compact manifolds. As applications, the Beckner inequality and the transportation cost inequality are established for a class of continuous spin systems. In particular, some results in [1, 2] are generalized.

关键词： Beckner inequality Continuous spin systems Transportation cost inequality

Pointwise characterizations of curvature and second fundamental form on Riemannian manifolds

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Science China Mathematics 2018年第8期61卷 1407-1420页

作者： fengyu Wang Bo Wu Center for Applied Mathematics Tianjin University Department of Mathematics Swansea University School of Mathematical Sciences Fudan University

Let M be a complete Riemannian manifold possibly with a boundary?*** any C^1-vector field Z,by using gradient/functional inequalities of the(reflecting)diffusion process generated by L:=?+Z,pointwise characterizations are presented for the Bakry-Emery curvature of L and the second fundamental form of?M if it *** characterizations extend and strengthen the recent results derived by Naber for the uniform norm‖RicZ‖∞on manifolds without boundaries.A key point of the present study is to apply the asymptotic formulas for these two tensors found by the first author,such that the proofs are significantly simplified.

关键词： curvature second fundamental form diffusion process path space

Determination of Hg^2＋ in Tap Water Based on the Electro- chemiluminescence of Ru（phen）3^2＋ and Thymine at Bare and Graphene Oxide-Modified Glassy Carbon Electrodes

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Chinese Journal of Chemistry 2016年第12期34卷 1297-1303页

作者： Yulong Gao Tao Wang fengyu Liu State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian Liaoning 116024 China School of Chemistry Dalian University of Technology Dalian Liaoning 116024 China

The electrochemiluminescence （ECL） of the Ru（phen）3^2＋/thymine （T） system at bare and graphene oxide （GO）-modified glassy carbon （GC） electrodes was utilized to determine Hg2＋ in tap water. The ECL intensity of Ru（phen）3^2＋ was considerably enhanced by the addition of thymine because of the occurrence of ECL tion between them. Subsequently, the ECL intensity of Ru（phen）3^2＋/T system rapidly decreased with the addition of Ru（phen）3^2＋ because of the formation ofa T-Hg^2＋-T complex. A linear response （R2=0.9914） was obtained over a Hg^2＋ concentration range of 1.0×10 9 mol/L to 1.0×10^-5 mol/L with a detection limit of 3.4×10^-10 mol/L at a bare GC electrode in 0.1 mol/L phosphate buffer （pH=8.0）. The detection limit can be further reduced to 4.2 ×10^-12 mol/L after modification of the GC electrode by GO. To verify its applicability, the proposed method was utilized to determine Hg^2＋ in tap water and simulated wastewater. The method exhibited good reproducibility and stability and thus reveals the possibility of developing a novel ECL detection method for Hg^2＋.

关键词： electrochemiluminescence (ECL) determination 2+ Hg thymine graphene oxide

Assembling ZnO Nanorods into Microflowers through a Facile Solution Strategy: Morphology Control and Cathodoluminescence Properties

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Nano-Micro Letters 2012年第1期4卷 45-51页

作者： Ying Lei fengyu Qu Xiang Wu Key Laboratory of Semiconductor Nanocomposite Materials Ministry of Education and College of Chemistry and Chemical EngineeringHarbin Normal University

In this work, flowerlike ZnO micro/nanostructures assembled from nanorods are obtained through a facile hydrothermal route. The experimental results indicated that the as-synthesized ZnO microflowers have an average diameter of 2 μm, composed of nanorods of an average diameter of 200 nm and a tapered *** with other morphologies were also obtained by varying the reaction conditions. Systematical conditiondependent experiments were conducted to reveal the growth mechansim of the microflowers. It is suggested that the zinc source types, solution p H value, and reaction temperature, as well as reaction time are responsible for the variations of ZnO morphology. Luminescence properties of ZnO microflowers were investigated through monitoring different parts of nanorods, showing good optical quality.

关键词： Microflowers Solution growth Zn O Cathodoluminescence

Expression of human augmenter of liver regeneration in pichia pastoris yeast and its bioactivity in vitro

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World Journal of Gastroenterology 2004年第21期10卷 3188-3190页

作者： QiLiu Hui-fengyu HangSun Hua-FengMa InstituteforViralHepatitis ChongqingUniversityofMedicalSciencesChongqing400010China

AIM:To construct a yeast expression system of human augmenter of liver regeneration (hALR) and to examine its bioactivity in v/***: With PCR and gene recombination techniques, cDNA of open reading frame of hALR was obtained from recombinant plasmid pcDNA3.1-hALR and inserted into plasmid pPIC9. The cDNA of hALR from recombinant plasmid pPIC9-hALR demonstrated by sequencing was subcloned into plasmid pPIC9K. The recombinant plasmid pPIC9KhALR was transformed into GSl15 with electroporation. hALR was expressed by GSl15 under the induction of 5 mL/L methanol and purified with ultrafiltration after it was analyzed by 15% SDS-PAGE and Western blot. The effects of hALR on in vitro proliferation of QGY and HepG2 cells were evaluated by ^3H-TdR methods. RESULTS: The correctness and integrity of recombinant plasmids pPIC9-hALR and pPIC9K-hALR were identified by restriction digestion, PCR and sequencing methods, respectively, hALR as a secretive protein was successfully expressed by GSl15. Its molecular weight was about 15 ku and the target protein was about 60% of the total protein in the supernatant from GSl15 with plasmid pPIC9K-hALR. The results of Western blot of hALR showed the specific band. The high qualitative hALR was obtained through ultrafiltration, hALR could stimulate in vitro proliferation of QGY and HepG2 cells in a dose-dependent manner, but there was a difference in reactivity to hALR between 0GY and HepG2. CONCLUSION: The hALR as a secretive protein can be successfully expressed by GSl15. It may stimulate in vitro proliferation of QGY and HepG2 cells at a dose-dependent manner. But QGY and HepG2 cells have different reactivities to hALR.

关键词：基因表达肝再生酵母生物活性毕苏酵母属消化系统

Cheeger's inequalities for general symmetric forms and existence criteria for spectral gap

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Chinese Science Bulletin 1998年第18期43卷 1516-1518页

作者： Mufa Chen fengyu Wang Department of Mathematics Beijing Normal University Beijing China

The Cheeger’s inequalities and some existence criteria for spectral gap and for general symmetric forms are established. The criteria are also extended to general reversible Markov processes but not reported here. Even though in the past several decades, the topics have been widely studied, as far as we know the first problem in the unbounded case and the second one in the general case remain open.

关键词： Cheeger’s inequality spectral gap Neumann and Dirichlet eigenvalue jump process.

How to Construct Marxian Thoughts as a Political Philosophy？.

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Frontiers of Philosophy in China 2015年第4期10卷 601-614页

作者： ZANG fengyu School of Philosophy Renmin University of China Beijing 100872 China

Importance of contemporary political philosophy has increased in recent decades. Since the 1970s, studies of Marx’s theories have become an important part of the discussion within contemporary theories of justice. More extensive studies concerning Marxist political philosophy from multiple perspectives are becoming a focal point in other fields of academic research. “How to understand Marx’s political philosophy?” has been a classic question for over a hundred years. Not an academic philosopher himself, Marx seems not to have issued a complete or consistent political philosophy by today’s standards, so it is only natural that his views would be interpreted differently by different scholars. While it is justifiable for us to construct Marx’s political philosophy, we must do it through a comprehensive theoretical reflection, and our construction must take full account of the history of the interpretations of Marx’s political philosophy. This applies especially of his theory of justice—a history which has lasted for more than a century. It is even more important for us to reread the original texts, particularly Marx’s early philosophical writings, and take them as the textual foundation for Marx’s political philosophy.

关键词： political philosophy Marxian thoughts inter-textual interpretation

Natural Feature-based Visual Servoing for Grasping Target with an Aerial Manipulator

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Journal of Bionic Engineering 2020年第2期17卷 215-228页

作者： Bin Luo Haoyao Chen fengyu Quan Shiwu Zhang Yunhui Liu School of Mechanical Engineering and Automation Harbin Institute of Technology ShenzhenShenzhen 518055China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China Department of Mechanical and Automation Engineering Chinese University of Hong KongHong Kong 999077China

Aerial transportation and manipulation have attracted increasing attention in the unmanned aerial vehicle field,and visual servoing methodology is widely used to achieve the autonomous aerial grasping of a target ***,the existing marker-based solutions pose a challenge to the practical application of target grasping owing to the difficulty in attaching markers on *** address this problem,this study proposes a novel image-based visual servoing controller based on natural features instead of artificial *** natural features are extracted from the target images and further processed to provide servoing feature points.A six degree-of-freedom(6-DoF)aerial manipulator system is proposed with differential kinematics deduced to achieve aerial ***,a controller is designed when the target object is outside a manipulator's workspace by utilizing both the degrees-of-freedom of nnmanned aerial vehicle and manipulator ***,a weight matrix is used as basis to develop a multi-tasking visual servoing framework to integrate the controllers inside and outside the manipulator's ***,experimental results are provided to verify the effectiveness of the proposed approach.

关键词： unmanned aerial manipulator visual servoing aerial grasping multi-tasking strategy

Co-or Ni-modified Sn-MnO_(x) low-dimensional multi-oxides for high-efficient NH_(3)-SCR De-NO_(x):Performance optimization and reaction mechanism

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Journal of Environmental Sciences 2022年第3期34卷 204-218页

作者： fengyu Gao Chen Yang Xiaolong tang Honghong Yi Chengzhi Wang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants University of Science and Technology BeijingBeijing 100083China

NH_(3)-SCR performances were explored to the relationship between structure morphology and physio-chemical properties over low-dimensional ternary Mn-based catalysts prepared by one-step synthesis *** to its strong oxidation performance,Sn-MnO_(x) was prone to side reactions between NO,NH_(3)and O_(2),resulting in the generation of more NO_(2)and N_(2)O,here most of N_(2)O was driven from the non-selective oxidation of NH_(3),while a small part generated from the side reaction between NH_(3)and NO_(2).Co or Ni doping into Sn-MnO_(x) as solid solution components obviously stronged the electronic interaction for actively mobilization and weakened the oxidation performance for signally reducing the selective tendency of side reactions to N_(2)*** optimal modification resulted in improving the surface area and enhancing the strong interaction between polyvalent cations in Co/Ni-Mn-SnO_(2)to provide more surface adsorbed oxygen,active sites of Mn^(3+) and Mn^(4+),high-content Sn^(4+) and plentiful Lewis-acidity for more active intermediates,which significantly broadened the activity window of Sn-MnOx,improved the N^(2) selectivity by inhibiting N_(2)O formation,and also contributed to an acceptable resistances to water and *** low reaction temperatures,the SCR reactions over three catalysts mainly obeyed the typical Elye-rideal(E-R)routs via the reactions of adsorbed L-NH_(x)(x=3,2,1)and B-NH_(4)^(+) with the gaseous NO to generate N_(2) but also N_(2)O *** for the above basic E-R reactions,as increasing the reaction temperature,the main adsorbed NO_(x)-species were bidentate nitrates that were also active in the Langmuir-Hinshelwood reactions with adsorbed L-NH_(x) species over Co/Ni modified Mn-SnO_(2) catalyst.

关键词： Low-dimensional catalysts One-step synthesis Mn-SnO_(2)nanosheet Ni or Co modification SCR performances Promotional mechanism