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Advances in noble metal-modified g-C_(3)N_(4) heterostructures toward enhanced photocatalytic redox ability

International Journal of Minerals,Metallurgy and Materials 2024年第11期31卷 2368-2389页

作者： Xiao Zhang ping Yang Faculty of Chemical Engineering and Technology Cracow University of TechnologyKrakow 31-155Poland School of Material Science&Engineering University of JinanJinan 250022China

The photocatalytic activity of catalysts depends on the energy-harvesting ability and the separation or transport of photogenerated *** light absorption capacity of graphitic carbon nitride(g-C_(3)N_(4))-based composites can be enhanced by adjusting the surface plasmon resonance(SPR)of noble metal nanoparticles(e.g.,Cu,Au,and Pd)in the entire visible *** can be carried out by varying the nanocomponents of the *** SPR of noble metals can enhance the local electromagnetic field and improve interband transition,and resonant energy transfer occurs from plasmonic dipoles to electron-hole pairs via near-field electromagnetic ***,noble metals have emerged as relevant nanocomponents for g-C_(3)N_(4) used in CO_(2) photoreduction and water ***,recent key advances in noble metals(either in single atom,cluster,or nanoparticle forms)and composite photocatalysts based on inorganic or organic nanocomponent-incorporated g-C_(3)N_(4) nanosheets are systematically discussed,including the applications of these photocatalysts,which exhibit improved photoinduced charge mobility in CO_(2) photoconversion and H2 *** related to the different types of multi-nanocomponent heterostructures(involving Schottky junctions,Z-/S-scheme heterostructures,noble metals,and additional semiconductor nanocomponents)and the adjustment of dimensionality of heterostructures(by incorporating noble metal nanoplates on g-C_(3)N_(4) forming 2D/2D heterostructures)are *** current prospects and possible challenges of g-C_(3)N_(4) composite photocatalysts incorporated with noble metals(e.g.,Au,Pt,Pd,and Cu),particularly in water splitting,CO_(2) reduction,pollution degradation,and chemical conversion applications,are summarized.

关键词： g-C_(3)N_(4) heterostructure noble metal photocatalysis H_(2)generation CO_(2)

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Pd-Catalyzed Intermolecular Dearomative Heck Reaction of Indole Derivatives

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Chinese Journal of Chemistry 2020年第5期38卷 525-526页

作者： ping Yang State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling LuShanghai 200032China

Dearomatization of indole derivatives[1,2]provides a straightforward approach for synthesizing diverse indolines which serve as the structural core of numerous natural products and pharmaceuticals.[3]Over the past decade,Pd-catalyzed Heck reaction[4]has been applied in the dearomatization of *** this regard,several elegant intramolecular dearomative Heck reactions of indoles have been developed.[s]However,to date,the reported works are mainly limited to intramolecular reactions,which proceed viaβ3-hydride elimination or trapping by an additional nucleophile(Scheme 1(a)).However,additional synthetic elaboration is usually required to access appropriate substrates for the key dearomatization step,thus reducing the synthetic efficiency.

关键词： intramolecular Heck straight

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Instance Segmentation and Berry Counting of Table Grape before Thinning Based on AS-SwinT

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Plant Phenomics 2023年第4期5卷 703-713页

作者： Wensheng Du ping Liu Shandong Agricultural Equipment Intelligent Engineering Laboratory Shandong Provincial Key Laboratory of HorticulturalMachinery and EquipmentCollege of Mechanical and Electronic EngineeringShandong Agricultural UniversityTai'an 271000China School of Construction Machinery Shandong Jiaotong UniversityJinan 250357China

Berry thinning is one of the most important tasks in the management of high-quality table *** often thin the berries per cluster to a standard number by *** an aging population,it is hard to find adequate skilled farmers to work during thinning *** is urgent to design an intelligent berry-thinning machine to avoid exhaustive repetitive labor.A machine vision system that can determine the number of berries removed and locate the berries removed is a challenge for the thinning machine.A method for instance segmentation of berries and berry counting in a single bunch is proposed based on *** AS-Swin T,Swin Transformer is performed as the backbone to extract the rich characteristics of grape *** adaptive feature fusion is introduced to the neck network to sufficiently preserve the underlying features and enhance the detection of small *** size of berries in the dataset is statistically analyzed to optimize the anchor scale,and Soft-NMS is used to filter the candidate frames to reduce the missed detection of densely shaded ***,the proposed method could achieve 65.7 AP^(box),95.0 AP^(box)_(0.5),57 AP^(box)_(s),62.8 AP^(mask)94.3 AP^(mask)_(0.5),48 AP^(mask)_(s),which is markedly superior to Mask R-CNN,Mask Scoring R-CNN,and Cascade Mask *** regressions between predicted numbers and actual numbers are also developed to verify the precision of the proposed *** and R^(2)values are 7.13 and 0.95,respectively,which are substantially higher than other models,showing the advantage of the AS-SwinT model in berry counting estimation.

关键词： Berry network removed

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Pressure Effects on Spectra of Tunable Laser Crystal GSGG：Cr^3＋ I：Theory

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Communications in Theoretical Physics 2003年第2期39卷 249-256页

作者： MADong－ping ZHANGJi－ping InternationalCentreforMaterialsPhysics AcademiaSinicaShenyang110015China DepartmentofAppliedPhysics SichuanUniversityChengdu610065China DepartmentofAppliedPhysics SichuanUniversit

A theory for shifts of energy spectra due to electron-phonon interaction (EPI) has been developed. Both the temperature-independent contributions and the temperature-dependent ones of acoustic branches and optical branches have been derived. It is found that the temperature-independent contributions are very important, especially at low temperature. The total pressure-induced shift (PS) of a level (or spectral line or band) is the algebraic sum of its PS without EPI and its PS due to EPI. By means of both the theory for shifts of energy spectra due to EPI and the theory for PS of energy spectra, the total PS of R1 line of tunable laser crystal GSGG:Cr3+ at 70 K as well as the ones of its R1 line, R2 line and U band at 300 K will be successfully calculated and explained in this series of papers.

关键词： high-pressure effect line shift spin-orbit interaction electron-phonon interaction d-orbital coupling between t(2)(2)(T-3(1))e(4)T(2) and t(2)(3) E-2 tunable laser crystal

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General Lyapunov Stability and Its Application to Time-Varying Convex Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第11期11卷 2316-2326页

作者： Zhibao Song ping Li the College of Mathematics and Systems Science Shandong University of Science and Technology

In this article, a general Lyapunov stability theory of nonlinear systems is put forward and it contains asymptotic/finite-time/fast finite-time/fixed-time stability. Especially, a more accurate estimate of the settling-time function is exhibited for fixedtime stability, and it is still extraneous to the initial *** can be applied to obtain less conservative convergence time of the practical systems without the information of the initial conditions. As an application, the given fixed-time stability theorem is used to resolve time-varying(TV) convex optimization *** the Newton's method, two classes of new dynamical systems are constructed to guarantee that the solution of the dynamic system can track to the optimal trajectory of the unconstrained and equality constrained TV convex optimization problems in fixed time, respectively. Without the exact knowledge of the time derivative of the cost function gradient, a fixed-time dynamical non-smooth system is established to overcome the issue of robust TV convex optimization. Two examples are provided to illustrate the effectiveness of the proposed TV convex optimization algorithms. Subsequently, the fixed-time stability theory is extended to the theories of predefined-time/practical predefined-time stability whose bound of convergence time can be arbitrarily given in advance, without tuning the system parameters. Under which, TV convex optimization problem is solved. The previous two examples are used to demonstrate the validity of the predefined-time TV convex optimization algorithms.

关键词： Fixed-time stability nonlinear system predefined-time stability time-varying(TV)convex optimization

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Product of Uniform Distribution and Stirling Numbers of the First Kind

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1435-1442页

作者： ping SUN Department of Mathematics Northeastern University Shenyang 110004 P. R. China

Let Vk=u1u2……uk, ui＇s be i.i.d - U（0, 1）, the p.d.f of 1 - Vk＋l be the GF of the unsigned Stirling numbers of the first kind s（n, k）. This paper discusses the applications of uniform distribution to combinatorial analysis and Riemann zeta function; several identities of Stifling series are established, and the Euler＇s result for ∑ Hn/n^k-l, k ≥ 3 is given a new probabilistic proof.

关键词： Stirling numbers generating function uniform distribution moment Riemann zeta function

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Remark on the Regularities of Kato's Solutions to Navier-Stokes Equations with Initial Data in L^d(R^d)

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Chinese Annals of Mathematics,Series B 2008年第3期29卷 265-272页

作者： ping ZHANG Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

Motivated by the results of J. Y. Chemin in ＂J. Anal. Math., 77, 1999, 27- 50＂ and G. Furioli et al in ＂Revista Mat. Iberoamer., 16, 2002, 605-667＂, the author considers further regularities of the mild solutions to Navier-Stokes equation with initial data uo ∈ L^d（R^d）. In particular, it is proved that if u C ∈（[0, T^＊）; L^d（R^d）） is a mild solution of （NSv）, then u（t,x）- e^vt△uo ∈ L^∞（（0, T）;B2/4^1,∞）~∩L^1 （（0, T）; B2/4^3 ,∞） for any T 〈 T^＊.

关键词： Navier-Stokes equations Kato's solutions Para-differential decomposition

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LOCATION AND ECONOMIC GROWTH:CASE STUDY IN CHINA

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Chinese Geographical Science 2004年第2期14卷 104-109页

作者： ZHONGChun-ping SchoolofEconomics HuazhongUniversityofScienceandTechnologyWuhan430074P.R.China

This paper explores how location could affect economic growth and it has always been omitted in economic analysis. Geographic factors can affect economic activities. Three mechanisms of location affecting economic growth have been studied: consumption, production and migration. The initial superior location will take such advantages as lower transport costs and lower price level, so it could have higher consumption utility, higher productivity, and attract more human capital, then lead higher growth. Those regions with the superior location will have higher utility due to more product varities and the comparative lower price, and higher wage due to the production technology, and it would attract more individuals with higher human capital to move to this location. It is a kind of agglomeration, meaning the superior location will hold more advantages and higher growth rate, otherwise those locations with poor geographic factor will be even worse. Based on Chinese provincial economic growth experiences of these years, this paper does some empirical analysis by regressing on some variables including the geographic ones. In this paper, the dummy variables and population density are used to measure the location factor. And we find evidences supporting the view that dominant locations such as coastal areas grow faster, on the contrary,middle and western provinces grow slower. Location does affect economic growth.

关键词： location economic growth advantage

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Structures,stabilities,and IR and ^(13)C-NMR spectra of dihedral fullerenes:A density functional theory study

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Science China Chemistry 2012年第9期55卷 1856-1871页

作者： LI ping College of Chemistry Sichuan UniversityChengdu 610064China

Dihedral fullerenes are thermodynamically stable molecules with Dnd or Dnh symmetry. Based on experimental findings, two series of dihedral fullerenes with five-fold （C5） and six-fold （C6） symmetry have been studied using density functional theory （DFT）. The DFT calculations showed that for both series the stabilities increased with increasing fullerene size. Structural analyses indicated that the stabilities are related to specific local geometries. In the case of the more abundant C5 series, the presence of approximately planar pentagons and hexagons on the top bowl favors their formation. That is to say, those fuller- enes with small dihedral angles within the polygons are readily formed, because planar hexagons lead to strengthened conjuga- tion which lowers average bonding energies （ABE） and increases thermodynamic stabilities. Non-planar hexagons at equatorial positions in tube-shaped fullerenes have an adverse effect on the conjugation and inhibit their formation. Calculations also demonstrated that fullerenes in the two series, including C50（D5h）, C60（O6h）, C80（O5d）, C96（D6d）, Cllo（D5h）, and Cl20（D5d）, have thermodynamically stable triplet structures with strong conjugation. The calculated IR and 13C NMR spectra of the fullerenes show some similarities and regular trends due to their homogenous structures. The electronic structures indicate that short dou- ble bonds in hexagons with high electron occupancies are readily attacked by electrophilic agents and can also be coordinated by transition metals. Mechanistic discussions suggested that C2 additions and C2 losses constitute reversible processes at high temperature and C2 additions in pentagonal fusions are crucial to the kinetics of the curvature of structures. C3 additions lead to the formation of large fullerenes of other types.

关键词： dihedral fullerene singlet and triplet structures IR and NMR spectra conjugate structure stability

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A Fairness-Enhanced Intelligent MAC Scheme Using Q-Learning-Based Bidirectional Backoff for Distributed Vehicular Communication Networks

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Tsinghua Science and Technology 2023年第2期28卷 258-268页

作者： ping Wang Shuai Wang College of Information Science and Technology Donghua UniversityShanghai 201620China

With the increasing attention to front-edge vehicular communication applications,distributed resource allocation is beneficial to the direct communications between vehicle ***,in highly dynamic distributed vehicular networks,quality of service(QoS)of the systems would degrade dramatically because of serious packet collisions in the absence of sufficient link *** on the fairness optimization,a Q-learning-based collision avoidance(QCA)scheme,which is characterized by an ingenious bidirectional backoff reward model RQCA corresponding to arbitrary backoff stage transitions,has been proposed in an intelligent distributed media access control *** QCA,an intelligent bidirectional backoff agent based on the Markov decision process model can actively motivate each vehicle agent to update itself toward an optimal backoff sub-intervel BSIopt through either positive or negative bidirectional transition individually,resulting in the distinct fair communication with a proper balance of the resource *** to the reinforcement learning theory,the problem of goodness evaluation on the backoff stage self-selection policy is equal to the problem of maximizing Q function of the vehicle in the current *** final decision on BSI_(opt) related to an optimal contention window range was solved through maximizing the Q value or Q_(max).The ε-greedy algorithm was used to keep a reasonable convergence of the Q_(max) *** the fairness evaluation of QCA,four kinds of dynamic impacts on the vehicular networks were investigated:mobility,density,payload size,and data rate with a network simulator ***,QCA can achieve fair communication efficiently and robustly,with advantages of superior Jain’s fairness index,relatively high packet delivery ratio,and low time delay.

关键词： media access control(MAC) fairness Q-learning-based collision avoidance(QCA) bidirectional backoff agent vehicular communication networks

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