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Robustness of the octupole collectivity in 144Ba within the cranking covariant density functional theory in 3D lattice

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Nuclear Science and Techniques 2024年第8期35卷 124-131页

作者： Ze‑Kai Li yuan‑yuan wang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The octupole deformation and collectivity in octupole double-magic nucleus 144Ba are investigated using the Cranking covariant density functional theory in a three-dimensional lattice *** reduced B(E3)transition probability is implemented for the first time in semiclassical approximation based on the microscopically calculated electric octupole *** available data,including the I-ωrelation and electric transitional probabilities B(E2)and B(E3)are well ***,it is shown that the ground state of 144Ba exhibits axial octupole and quadrupole deformations that persist up to high spins(I≈24h).

关键词： Octupole collectivity Cranking covariant density functional theory Rotational spectrum Electric transitional probabilities

Fe_(0.02)/Ag_(x)-ZnO复合材料的合成及其光催化活性

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陕西科技大学学报 2025年第1期43卷 88-100页

作者：王远港王有杰孙铖赵显一渤海大学化学与材料工程学院辽宁锦州121013 锦州晨晟科技有限公司辽宁锦州121013

采用水热合成法及煅烧法,制备了不同掺杂量的Fe_(0.02)/Ag_(x)-ZnO复合材料,并考察了各催化剂对RhB光催化降解活性.机理分析表明,Fe掺杂进ZnO,Fe^(3+)可以形成陷阱捕获e-,导致ZnO的导带下方形成一个Fe掺杂能级,促使缩短了ZnO的带隙,扩... 详细信息

采用水热合成法及煅烧法,制备了不同掺杂量的Fe_(0.02)/Ag_(x)-ZnO复合材料,并考察了各催化剂对RhB光催化降解活性.机理分析表明,Fe掺杂进ZnO,Fe^(3+)可以形成陷阱捕获e-,导致ZnO的导带下方形成一个Fe掺杂能级,促使缩短了ZnO的带隙,扩大了光谱响应范围;Ag的掺入促使部分电子(e^(-))跃迁到Ag单质上,减小了禁带宽度,降低了电子跃迁所需的能量,抑制了e^(-)-h^(+)的复合,Fe_(0.02)/Ag_(x)-ZnO样品的新费米能级低于Fe-ZnO和ZnO的导带能级,导致其界面处的电荷分离;进一步研究Fe_(0.02)/Ag_(x)-ZnO复合材料对染料罗丹明B(Rhodamine B,RhB)的光催化降解性能和循环使用性能.结果表明,Fe_(0.02)/Ag_(x)-ZnO复合材料可作为一种稳定、高效且可循环的光催化剂材料并用于污水处理,拓展了Fe_(0.02)/Ag_(x)-ZnO复合材料的应用.

关键词：电子跃迁费米能级禁带宽带光催化

Global adaptive output-feedback tracking with prescribed performance for uncertain nonlinear systems

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Science China(Information Sciences) 2024年第5期67卷 150-164页

作者： yuan wang Yungang LIU School of Control Science and Engineering Shandong University

At present, one typical control strategy for guaranteeing transient and steady-state performance is funnel control and prescribed performance control. The strategy features completely discarding the system nonlinearities, even if they are completely known and available. Such an intrinsic feature requires the controller to produce a larger control effect to eliminate the negative impact caused by the high nonlinearities, leading to a conservative controller. In this paper, we fully take advantage of known information on nonlinearities in control design, instead of completely discarding it as done in funnel control. Particularly, we leverage adaptive techniques(i.e., high-gain dynamic compensation) to deal with unknown system nonlinearities. Meanwhile, we integrate the tools of output feedback, tracking control, and the performance *** such, an adaptive output-feedback scheme is developed for global tracking with spatiotemporal performance specifications: arbitrarily given tracking accuracy and accuracy-ensured time. A simulation example supports the developed approach.

关键词： uncertain nonlinear systems output feedback prescribed performance unknown control direction dynamic high gain global tracking

Adaptive output-feedback tracking for nonlinear systems with unknown control direction and generic inverse dynamics

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Science China(Information Sciences) 2022年第8期65卷 134-149页

作者： yuan wang Yungang LIU School of Control Science and Engineering Shandong University

This paper studies adaptive output-feedback tracking for a class of typical uncertain nonlinear systems. In the context of unknown control direction, a generic uncertainty encountered inevitably in practice is adequately taken into consideration, i.e., the ISpS(input-to-state practically stable) inverse dynamics acting as the dynamic differences between the real plants and the models. Besides, the systems in question also permit two critical ingredients, i.e., unmeasured-state dependent nonlinearities and arbitrary functionof-output growth on unknown system nonlinearities. The three ingredients together largely challenge the feasibility/availability of practical tracking by means of output feedback. Nevertheless, a new control strategy is proposed by flexibly integrating the dynamic compensation based on Nussbaum-type gain, backstepping design technique together with the refined pseudo-sign and pseudo-dead-zone functions that were introduced for the first time in our previous studies. The two refined functions, which are sufficiently smooth, can moderately avoid the use of smooth domination/treatment in control design and can potentially render the attained control strategy tighter and less conservative. Moreover, to keep the order of the closed-loop system at a low level, an n-dimensional filter with a dynamic high gain is delicately devised instead of a2 n-dimensional one used in the relevant literature. It turns out that the proposed adaptive output-feedback controller is capable of guaranteeing the global boundedness of all states of the resulting closed-loop system,while steering the system tracking error to enter, in finite time, a prescribed λ-neighborhood of the origin and keeping it inside thereafter. A simulation example is provided to demonstrate the proposed approach.

关键词： nonlinear systems ISpS inverse dynamics unknown control direction practical output tracking global output feedback adaptive compensation

Effects of pH on photochemical decomposition of perfluorooctanoic acid in different atmospheres by 185 nm vacuum ultraviolet

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Journal of Environmental Sciences 2014年第11期26卷 2207-2214页

作者： yuan wang Pengyi Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University School of Chemistry and Chemical Engineering Guizhou University

Perfluorooctanoic acid （PFOA）, a persistent organic pollutant, receives increasing concerns due to its worldwide occurrence and resistance to most conventional treatment processes. The photochemical decomposition by 185 nm vacuum ultraviolet （VUV） is one of the efficient methods for PFOA decomposition. The effects of pH on PFOA decomposition in nitrogen atmosphere or oxygen atmosphere were investigated. At its original pH （4.5） of PFOA aqueous solution, PFOA decomposed efficiently both in nitrogen and in oxygen atmosphere. However, when the pH increased to 12.0, PFOA decomposition was greatly inhibited in oxygen atmosphere, while it was greatly accelerated in nitrogen atmosphere with a very short half-life time （9 rain）. Furthermore, fluorine atoms originally contained in PFOA molecules were almost completely transformed into fluoride ions. Two decomposi- tion pathways have been proposed to explain the PFOA decomposition under different conditions. In acidic and neutral solutions, PFOA predominantly decomposes via the direct photolysis in both atmospheres; while in the alkaline solution and in the absence of oxygen, the decomposition of PFOA is mainly induced by hydrated electrons.

关键词： Perfluorocarboxylic acids (PFCAs)185 nm vacuum ultraviolet Persistent organic pollutants Photochemical Perfluorinated compounds

Toward Artificial Peptide Nanocapsules

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Nano-Micro Letters 2024年第10期16卷 240-243页

作者： yuan wang Bing Chen Laboratory for Biomaterials and Drug Delivery Department of AnesthesiologyDivision of Critical Care MedicineBoston Children's HospitalHarvard Medical SchoolBostonMA 02115USA College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023People's Republic of China

HIGHLIGHTS The formation of peptide nanocapsules is facilitated by a gradient interface,where the differential solvent concentration drives the peptides to preferentially localize and *** peptide nanocapsules,characterized by their hollow structures,demonstrated potential as carriers for targeted drug delivery.1 Introduction Peptide nanocapsules are a type of nanoscale delivery system that encapsulates active substances within a shell composed of peptides,leveraging the unique properties of peptides such as biocompatibility and biodegradability[1].Historically,the development of peptide nanocapsules was inspired primordially by the natural biological processes.

关键词： Peptide nanocapsules Self-assembly Drug delivery Nanomedicine

Air Pollution or Global Warming:Attribution of Extreme Precipitation Changes in Eastern China—Comments on “Trends of Extreme Precipitation in Eastern China and Their Possible Causes”

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Advances in Atmospheric Sciences 2015年第10期32卷 1444-1446页

作者： yuan wang Jet Propulsion Laboratory California Institute of Technology

The recent study ＂Trends of Extreme Precipitation in Eastern China and Their Possible Causes＂ attributed the observed decrease/increase of light/heavy precipitation in eastern China to global warming rather than the regional aerosol effects. However, there exist compelling evidence from previous long-term observations and numerical modeling studies, suggesting that anthropogenic pollution is closely linked to the recent changes in precipitation intensity because of considerably modulated cloud physical properties by aerosols in eastern China. Clearly, a quantitative assessment of the aerosol and greenhouse effects on the regional scale is required to identify the primary cause for the extreme precipitation changes.

关键词： aerosol effects global warming extreme precipitation

Generalized fairing algorithm of parametric cubic splines

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第9期7卷 1572-1577页

作者： wang yuan-jun CAO yuan School of Mathematical Science Fudan University Shanghai 200433 China

Kjellander has reported an algorithm for fairing uniform parametric cubic splines. Poliakoff extended Kjellander’s algorithm to non-uniform case. However, they merely changed the bad point’s position, and neglected the smoothing of tangent at bad point. In this paper, we present a fairing algorithm that both changed point’s position and its corresponding tangent vector. The new algorithm possesses the minimum property of energy. We also proved Poliakoff’s fairing algorithm is a deduction of our fairing algorithm. Several fairing examples are given in this paper.

关键词： Curve fairing Tangent vector Energy optimization Cubic splines

Images of Azurin Protein Studied by AFM

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Chemical Research in Chinese Universities 2004年第4期20卷 437-439页

作者： wang Nan wang yuan-liang Biomedical Engineering Department Chongqing UniversityChongqing 400044P.R.China Inorganic Chemistry Department South Parks RoadUniversity of OxfordOX13QRUK

Azurins, a wild type and a genetically mutant K27 altered one, were immobilized on annealed gold surface and investigated by means of atomic force microscopy. It was found that the surface coverage and height distribution of the adsorbed protein molecules are different from each other, which is possibly the result of the different orientation on the surface. It is believed that the wild type azurin is connected to gold surface by the disulphide bridge; while the mutant, K27C, might be through the thiol groups of the cysteine residues on their surface.

关键词： Atomic force microscopy Protein Azurin Topography