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specific *** valorem taxation and social welfare in mixed duopoly with foreign ownership

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Economic and Political studies 2024年第2期12卷 207-219页

作者： Ming sun Leonard F.s.Wang Qidi zhang school of Economics and Management Chang’an UniversityXi’anChina Wenlan school of business Zhongnan University of Economics and LawWuhanChina

In this paper,we set up a mixed duopoly competition model between state-owned and private firms in order to compare specific and ad valorem *** that the total output under specific and ad valorem taxation remains unchanged,we find that if the public firm is completely privatised,the output of the private firm under the two tax schemes will be the *** the public firm is not completely privatised,the output of the the private firm under specific taxation will be greater than that under ad valorem *** the private firm is a pure local one,the social benefits will be the same under the two tax ***,if the private firm is a joint venture that involves domestic and foreign entities,social welfare under ad valorem taxation will be greater than that under specific taxation.

关键词： specific taxation ad valorem taxation mixed duopoly imperfect competition privatisation foreign ownership

Modulating redox transition kinetics by anion regulation in Ni-Fe-X(X=O,s,se,N,and P)electrocatalyst for efficient water oxidation

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Nano Research 2024年第6期17卷 4720-4728页

作者： Liting Wei Kaini zhang Rui Zhao Lei zhang Yan zhang suyi Yang Jinzhan su International Research Center for Renewable Energy&state Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Applied Chemistry Yuncheng UniversityYuncheng 044000China

NiFe-based electrocatalysts will experience dynamical surface reconstruction during oxygen evolution reaction(OER)process,and the derived metal(oxy)hydroxide hybrids on the surface have been considered as the actual active species for *** efforts have been dedicated to understanding the surface reconstruction,but there is rare research on recognizing the origin of improved performance derived from anion species of ***,the OER electrocatalytic characteristics were tuned with different anions in NiFe-based catalyst,using NiFe-based oxides/nitride/sulfide/selenides/phosphides(NiFeX,X=O,N,s,se,and P)as the model *** combination of X-ray photoelectronic spectroscopy,electrochemical tests,operando spectroscopic characterizations,and density functional theory(DFT)calculations,reveals that anion with lower electronegativity in NiFe-based catalyst leads to higher conductivity and delayed valence transition of Ni sites,as well as optimized adsorption behavior towards oxygen intermediates,contributing to enhanced OER ***,NiFeP electrocatalyst demonstrates an ultralow overpotential of 265 mV at 20 mA·cm−2 for OER,as well as long-term *** work not only offers further insights into the effect of anionic electronegativity on the intrinsic OER electrocatalytic properties of NiFe-based electrocatalyst but also provides guide to design efficient non-noble metal-based electrocatalysts for water oxidation.

关键词： oxygen evolution reaction(OER) anion species electronegativity valence transition

Cyclodextrin nanofilms with hydrophobic and hydrophilic channels for solvent permeation and molecular sieving

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Nano Research 2024年第7期17卷 6638-6644页

作者： Kai zhang Yu Dai Yongli shi Zhaoxin zhang Linji Li Xiaojin zhang Fan Xia Faculty of Materials science and Chemistry China University of GeosciencesWuhan 430074China Henan Academy of Geology Zhengzhou 450052China

Nanofilms that can fast permeate solvents and accurately sieve molecules are of significant importance for separation.A promising strategy is to align the inner cavities of macrocycles into the channels within nanofilms,and control the channel size by selecting the ***,the channels outside the macrocycles are ***,we prepare nanofilms with hydrophobic channels(cyclodextrin inner cavity)and hydrophilic channels(cyclodextrin outer space)through interfacial polymerization of azobenzene-4,4’-dicarbonyl dichloride and amino-functionalizedβ-*** utilizing the significant geometric changes caused by the photoisomerization of azobenzene,nanofilms with adjustable hydrophilic channel sizes were *** nanofilms have high permeability to polar and non-polar solvents,and can distinguish molecules with almost the same molecular weight but different *** work expands the development of next-generation nanofilms generated through interfacial polymerization by incorporating rational molecular design.

关键词： nanofilm β-cyclodextrin azobenzene interfacial polymerization solvent permeation molecular sieving

Taiji-TianQin-LIsA network:Precisely measuring the Hubble constant using both bright and dark sirens

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science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 59-77页

作者： shang-Jie Jin Ye-Zhu zhang Ji-Yu song Jing-Fei zhang Xin zhang Key Laboratory of Cosmology and Astrophysics(Liaoning)&College of sciences Northeastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers science Center for Industrial Intelligence and systems Optimization Northeastern UniversityShenyang 110819China

In the coming decades,the space-based gravitational-wave(GW)detectors such as Taiji,TianQin,and LIsA are expected to form a network capable of detecting millihertz GWs emitted by the mergers of massive black hole binaries(MbHbs).In this work,we investigate the potential of GW standard sirens from the Taiji-TianQin-LIsA network in constraining cosmological *** the optimistic scenario in which electromagnetic(EM)counterparts can be detected,we predict the number of detectable bright sirens based on three different MbHb population models,i.e.,popⅢ,Q3d,and *** results show that the TaijiTianQin-LIsA network alone could achieve a constraint precision of 0.9%for the Hubble constant,meeting the standard of precision ***,the Taiji-TianQin-LIsA network could effectively break the cosmological parameter degeneracies generated by the CMb data,particularly in the dynamical dark energy *** combined with the CMb data,the joint CMb+Taiji-TianQin-LIsA data offerσ(w)=0.036 in the wCDM model,which is close to the latest constraint result obtained from the CMb+sN *** also consider a conservative scenario in which EM counterparts are not *** to the precise sky localizations of MbHbs by the Taiji-TianQin-LIsA network,the constraint precision of the Hubble constant is expected to reach 1.2%.In conclusion,the GW standard sirens from the Taiji-TianQin-LIsA network will play a critical role in helping solve the Hubble tension and shedding light on the nature of dark energy.

关键词： space-based gravitational wave detection standard sirens the Taiji-TianQin-LIsA network the Hubble constant dark energy

Unsaturated bi-heterometal clusters in metal-vacancy sites of 2D Mos2 for efficient hydrogen evolution

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Carbon Energy 2024年第3期6卷 264-275页

作者： Gonglei shao Jie Xu shasha Gao zhang zhang song Liu Xu zhang Zhen Zhou Interdisciplinary Research Center for sustainable Energy science and Engineering(IRC4sE2) School of Chemical EngineeringZhengzhou UniversityZhengzhouHenanChina College of Chemistry and Materials Engineering Wenzhou UniversityWenzhouZhejiangChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjinChina state Key Laboratory of Chemo/biosensing and Chemometrics Institute of Chemical Biology and Nanomedicine(ICBN)College of Chemistry and Chemical EngineeringHunan UniversityChangshaHunanChina Institute of New Energy Material Chemistry School of Materials Science and EngineeringNankai UniversityTianjinChina

The valence states and coordination structures of doped heterometal atoms in two-dimensional(2D)nanomaterials lack predictable regulation ***,a robust method is proposed to form unsaturated heteroatom clusters via the metal-vacancy restraint mechanism,which can precisely regulate the bonding and valence state of heterometal atoms doped in 2D molybdenum *** unsaturated valence state of heterometal Pt and Ru cluster atoms form a spatial coordination structure with Pt–s and Ru–O–s as catalytically active *** them,the strong binding energy of negatively charged suspended s and O sites for H+,as well as the weak adsorption of positively charged unsaturated heterometal atoms for H*,reduces the energy barrier of the hydrogen evolution reaction proved by theoretical ***,the electrocatalytic hydrogen evolution performance is markedly improved by the ensemble effect of unsaturated heterometal atoms and highlighted with an overpotential of 84 mV and Tafel slope of 68.5 mV dec^(−1).In brief,this metal vacancy-induced valence state regulation of heterometal can manipulate the coordination structure and catalytic activity of heterometal atoms doped in the 2D atomic lattice but not limited to 2D nanomaterials.

关键词： clusters hydrogen evolution reaction metal vacancy Mos2 unsaturated heterometal

Indispensable gutter layers in thin-film composite membranes for carbon capture

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Green Energy & Environment 2024年第8期9卷 1220-1238页

作者： Gengyi zhang Haiqing Lin Department of Chemical and biological Engineering University at Buffalo The State University at New York

Industrial thin-film composite(TFC) membranes achieve superior gas separation properties from high-performance selective layer materials,while the success of membrane technology relies on high-performance gutter layers to achieve production scalability and low-cost manufacturing. However, the current literature predominantly focuses on the design of polymer architectures to obtain high permeability and selectivity, while the art of fabricating gutter layers is usually safeguarded by industrial manufacturers and appears lackluster to academic researchers. This is the first report aiming to provide a comprehensive and critical review of state-of-the-art gutter layer materials and their design and modification to enable TFC membranes with superior separation performance. We first elucidate the importance of the gutter layer on membrane performance through modeling and experimental results. Then various gutter layer materials used to obtain high-performance composite membranes are critically reviewed, and the strategies to improve their compatibility with the selective layer are highlighted, such as oxygen plasma treatment, polydopamine deposition, and surface grafting. Finally, we present the opportunities of the gutter layer design for practical applications.

关键词： Thin-film composite membranes Gutter layer Gas separation Carbon capture

User Purchase Intention Prediction based on Improved Deep Forest

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Computer Modeling in Engineering & sciences 2024年第4期139卷 661-677页

作者： Yifan zhang Qiancheng Yu Lisi zhang school of Computer science and Engineering North Minzu UniversityYinchuan750030China Laboratory of Graphics and Images of the state Ethnic Affairs Commission North Minzu UniversityYinchuan750030China

Widely used deep neural networks currently face limitations in achieving optimal performance for purchase intention prediction due to constraints on data volume and hyperparameter *** address this issue,based on the deep forest algorithm and further integrating evolutionary ensemble learning methods,this paper proposes a novel Deep Adaptive Evolutionary Ensemble(DAEE)*** model introduces model diversity into the cascade layer,allowing it to adaptively adjust its structure to accommodate complex and evolving purchasing behavior ***,this paper optimizes the methods of obtaining feature vectors,enhancement vectors,and prediction results within the deep forest algorithm to enhance the model’s predictive *** demonstrate that the improved deep forest model not only possesses higher robustness but also shows an increase of 5.02%in AUC value compared to the baseline ***,its training runtime speed is 6 times faster than that of deep models,and compared to other improved models,its accuracy has been enhanced by 0.9%.

关键词： Purchase prediction deep forest differential evolution algorithm evolutionary ensemble learning model selection

A sINGULAR DIRICHLET PRObLEM FOR THE MONGE-AMPÈRE TYPE EQUATION

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Acta Mathematica scientia 2024年第5期44卷 1965-1983页

作者： Zhijun zhang bo zhang school of Mathematics and Information science Yantai UniversityYantai264005China

We consider the singular Dirichlet problem for the Monge-Ampère type equation{\rm det}\D^2 u=b(x)g(-u)(1+|\nabla u|^2)^{q/2},\u<0,\x\in\Omega,\u|_{\partial\Omega}=0,whereΩis a strictly convex and bounded smooth doma... 详细信息

We consider the singular Dirichlet problem for the Monge-Ampère type equation{\rm det}\D^2 u=b(x)g(-u)(1+|\nabla u|^2)^{q/2},\us a strictly convex and bounded smooth domain inℝn,q∈[0,n+1),g∈C∞(0,∞)is positive and strictly decreasing in(0,∞)with\lim\limits_{s\rightarrow 0^+}g(s)=\infty,and b∈C∞(Ω)is positive inΩ.We obtain the existence,nonexistence and global asymptotic behavior of the convex solution to such a problem for more general b and *** approach is based on the Karamata regular variation theory and the construction of suitable sub-and super-solutions.

关键词： Monge-Ampère equation a singular boundary value problem the unique convex solution global asymptotic behavior

Design and identification of a double-acting piezoelectric-hydraulic hybrid actuator

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Chinese Journal of Aeronautics 2024年第3期37卷 456-467页

作者： Junjian zhang Zhihua FENG Key Laboratory of Precision scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China

Traditional single-acting piezoelectric-hydraulic hybrid actuators usually have the problem of inertial force caused by flow pulsation of the liquid,which degrades their output *** suppress or solve the associated inertial force and enhance its output capabilities,this paper proposes a new type of double-acting piezoelectric-hydraulic hybrid actuator with four check valves acting as mechanical *** new hybrid actuator was fabricated and its output performance was *** the voltage is 700 Vp-pand the bias pressure is 2 MPa,the pulsation ratesδof the new actuator at 400 Hz,500 Hz and 600 Hz are 2.29,2.08 and 1.78,respectively,whileδof the single-acting hybrid actuator under the same conditions are 10.98,11.05 and ***,the liquid pulsation rate of the new hybrid actuator is significantly reduced,which is beneficial for improving the flow uniformity and weakening the influence of inertial force on the hybrid *** strategy ultimately leads to a maximum no-load velocity of 168.1 mm/s at 600 Hz and a maximum blocking force of 141 N at 450 Hz for the new hybrid *** addition,this strategy has the potential to be used in other electrohydrostatic actuators to improve their performance.

关键词： Double-acting Flow pulsation Inertial force Piezoelectric actuators Piezoelectric devices Piezoelectric hydraulic actuation Piezoelectric pump