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Interacting leaf dynamics and environment to optimize maize sowing date in North China Plain

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Journal of Integrative Agriculture 2020年第5期19卷 1227-1240页

作者： TIAN Bei-jing ZHU Jin-cheng liu xi-wei HUANG Shou-bing WANG pu College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193P.R.China Hebei Academy of Agriculture and Forestry Sciences Shijiazhuang 050035P.R.China

Leaf growth and its interaction with the growing environment critically affect leaf area, distribution, and function, and ultimately affects grain yield of maize(Zea mays L.). To detect the effects of leaf area dynamics, growth periods, and the environment on maize grain yield, a three-year field experiment was conducted using two maize varieties, medium plant-size variety Zhengdan 958(ZD958) and large plant-size variety Zhongnongda 4(ZND4), and three to five sowing dates. The sowing date significantly affected maize yield as a result of changes in leaf area, growth stage, and growing environment. Prior to the 12 th leaf stage, significant correlations between leaf area dynamics, environment, and yield were seldom detected. The expansion of leaf area from 12 th leaf stage to silking stage was significantly positively correlated with growing degree days(GDD), solar radiation, and grain yield, indicating the importance of leaf area dynamics during this period. After silking, solar radiation played a more important role in inducing leaf senescence than GDD, particularly in the 2 nd half of the grain filling stage. Accelerated leaf senescence in late growth period can increase maize yield. The environment affected leaf area dynamics and yield of the large plant-size variety(ZND4) more easily than the medium plant-size variety(ZD958) at the optimum plant density, reflecting the difference in varietal capacity to adapt to the growing environment. This study indicates that optimizing the interaction among leaf area dynamics, growth periods, and environment is a sound strategy to increase maize yield. Favorable interactions are useful to determine the optimal sowing date of a given variety.

关键词： canopy structure leaf dynamics growing environment maize yield

Hybrid Exciton—Polaritons in a Bad Microcavity Containing the Organic and Inorganic Quantum Wells

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Communications in Theoretical Physics 2001年第1期35卷 118-120页

作者： liuYu－xi SUNChang－pu InstituteofTheoreticalPhysics AcademiaSinicaP.O.Box2735Beijing100080China

We study the hybrid exciton-polaritons in a bad microcavity containing the organic and inorganic quantum wells. The corresponding polariton states are given. The analytical solution and numerical result of the station... 详细信息

关键词： quantum description of interaction of light and matter related experiment exciton and related phenomena

Nonlinear Schrödinger Approximation for the Electron Euler-Poisson Equation

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Chinese Annals of Mathematics,Series B 2023年第3期44卷 361-378页

作者： Huimin liu Xueke pu Faculty of Applied Mathematics Shanxi University of Finance and EconomicsTaiyuan030006China School of Mathematics and Information Sciences Guangzhou UniversityGuangzhou510006China

The nonlinear Schr?dinger(NLS for short)equation plays an important role in describing slow modulations in time and space of an underlying spatially and temporarily oscillating wave *** this paper,the authors study the NLS approximation by providing rigorous error estimates in Sobolev spaces for the electron Euler-Poisson equation,an important model to describe Langmuir waves in a *** derive an approximate wave packet-like solution to the evolution equations by the multiscale analysis,then they construct the modified energy functional based on the quadratic terms and use the rotating coordinate transform to obtain uniform estimates of the error between the true and approximate solutions.

关键词： Modulation approximation Nonlinear Schrödinger equation Electron Euler-Poisson equation

Selective catalytic hydrogenation of naphthalene to tetralin over a NiMo/Al2O3 catalyst

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2566-2576页

作者： xiaoping Su pu An Junwen Gao RuchengWang Yujuan Zhang xi Li Yangkun Zhao Yongqi liu xiaoxun Ma Ming Sun School of Chemical Engineering Northwest UniversityInternational Science&Technology Cooperation Base of MOST for Clean Utilization of Hydrocarbon ResourcesChemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei EnergyShaanxi Research Center of Engineering Technology for Clean Coal ConversionCollaborative Innovation Center for Development of Energy and Chemical Industry in Northern ShaanxiXi'an 710069China Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi'an 710069China

The selective catalytic hydrogenation of naphthalene to high-value tetralin was systematically investigated.A series of Al2O3 catalysts containing different active metals(Co,Mo,Ni,W)were prepared by incipient wetness *** effects of different active metals forms(oxidation,reduction,sulfuration)and reaction conditions on naphthalene hydrogenation were investigated and the catalysts were characterized by XRD,XPS,BET,NH3-TPD and ***,Ni-Mo/Al2O3 was first used in this reactive *** results show that the oxidative4%Ni O-20%MoO3/Al2O3 is the best catalyst for the preparation of *** conversion of naphthalene and the selectivity of tetralin can reach 95.62%and 99.75%respectively at 200℃,8 h and 6 *** with reduced and sulfureted 4%Ni O-20%MoO3/Al2O3 catalysts,oxidative 4%Ni O-20%MoO3/Al2O3 has a well dispersed and uniform monolayer of the active metals,larger pore volume and size,and larger total ***-MoO3/Al2O3 has a synergistic effect between NiO activity and MoO3 selectivity.

关键词： Naphthalene Tetralin Ni-Mo/Al2O3 catalysts

Bifunctional PdPt bimetallenes for formate oxidation-boosted water electrolysis

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Carbon Energy 2023年第12期5卷 175-186页

作者： xi-Lai liu Yu-Chuan Jiang Jiang-Tao Huang Wei Zhong Bin He pu-Jun Jin Yu Chen Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid Chemistry(Ministry of Education)Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'anShaanxiPR China College of New Materials and New Energies Shenzhen Technology UniversityShenzhenGuangdongPR China

Small-molecule electrooxidation-boosted water electrolysis(WE)is an energy-saving method for hydrogen(H2)***,PdPt bimetallenes(PdPt BMLs)are obtained through the simple galvanic replacement *** BMLs reveal 2.93-fold enhancement in intrinsic electroactivity and 4.53-fold enhancement in mass electroactivity for the formate oxidation reaction(FOR)with respect to Pd metallenes(Pd MLs)at 0.50 V potential due to the synergistic ***,the introduction of Pt atoms also considerably increases the electroactivity of PdPt BMLs for hydrogen evolution reaction(HER)with respect to Pd MLs in an alkaline medium,which even exceeds that with the use of commercial Pt *** by the outstanding FOR and HER electroactivity of bifunctional PdPt BMLs,a two-electrode FOR-boosted WE system(FOR-WE)is constructed by using PdPt BMLs as the cathode and the *** FOR-WE system only requires an operational voltage of 0.31 V to achieve H2 production,which is 1.48 V lower than that(ca.1.79 V)with the use of the traditional WE system.

关键词： electrocatalyst formate oxidation reaction hydrogen evolution reaction metallene water electrolysis

Dynamics of Optically Driven Exciton and Quantum Decoherence

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Communications in Theoretical Physics 2003年第6期39卷 723-728页

作者： JINGuang-Ri liuYu-xi ZHOUDuan-Lu SUNChang-pu InstituteofTheoreticalPhysics AcademiaSinicaBeijing100080China TheGraduateUniversityforAdvancedStudies(SOKEN) HayamaKanagawa240-0193Japan

By using the normal ordering method, we study the state evolution of an optically driven excitons in a quantum well immersed in a leaky cavity, which was introduced by Yu-xi liu et al. [Phys. Rev. A 63 (2001) 033816]. The influence of the external laser field on the quantum decoherence of a mesoscopically superposed state of the excitons is investigated. Our result shows that, the classical field can compensate the energy dissipation of the excitons. Although the decoherence rate of the excitonic Schr?dinger cat state does not depend on the external field, the phase of the decoherence factor can be well controlled by adjusting the amplitude of the external field as well as the detuning between the field and the transition frequency of the atom.

关键词： exciton quantum decoherence

A Preliminary Study on Silver Isotopic Composition in Polymetallic Ore Deposits in Eastern China

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Journal of Earth Science 2022年第1期33卷 100-108页

作者： Ge Dong Hai-Zhen Wei Yuanfeng Zhu xi liu Qi Guo Wei pu Yibo Lin Junlin Wang State Key Laboratory for Mineral Deposits Research Department of Earth Sciences and EngineeringNanjing University CAS Center for Excellence in Comparative Planetology

A preliminary survey of silver isotopic composition in four polymetallic ores in eastern China shows a larger variation inδ^(109)Ag from-0.014‰to+0.983‰,which is within the total ranges for the entire respective ore deposit types *** diversity of silver isotopic compositions in oredeposits reported here and previous studies seemed to preclude simple isotopic links to particular sources,but reflected the silver isotope fractionation in transport-and deposit-related processes ***δ^(109)Ag values in supergene samples from the Qixiashan Pb-Zn-Ag polymetallic deposit are more positive,in consistent with the statistical δ^(109)Ag distribution from-0.4‰to+2.2‰in 36 pieces of supergene ore samples around the World,which reflects the diverse controls on silver isotope fractionation from the first-order thermodynamic effect,reduction-mediated reaction,remobilization of silver with surficial low-temperature weathering *** hypogene samples in Dazhuangzi orogenic Au-Ag ore deposit,have δ^(109)Ag values close to 0,which implies that equilibrium partitioning associated with metal sources at the high-temperature does not result in a resolvable difference in silver isotopic *** contrast,the hypogene samples which are dominated by pyrite without visible silver minerals (i.e.,skarn iron ore deposit in Edongnan) have shown the largest variation range of δ^(109)Ag,followed by that from the porphyry copper ore in *** could be concluded that the surface adsorption and/or lattice substitution are important factors to control Ag isotope fractionation in oreforming processes,especially for skarn deposits with only *** perspective of silver isotope shows great potentials to understand the processes that lead to the concentrations of metals to economic levels and to constrain the physicochemical conditions during ore-mineralization in metallic ore-deposits.

关键词： silver isotopic composition hypogene ore deposits supergene ore deposits metal transport ore deposits

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Strategic integration of 2D perovskite and chiral quantum dot hybrid heterostructures for superior CPL detection

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Science China Technological Sciences 2025年第1期 368-377页

作者： Jiahe YAN xi ZHANG Lei liu Hualin BI Mengke WANG Jing LI Jun WANG Department of Chemistry College of SciencesNortheastern University Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Circularly polarized light（CPL） detection has garnered significant research interest due to its extensive applications in optoelectronics and quantum *** perovskites possess CPL detection capabilities due to their inherent ***,incorporating organic amine spacers distorts the crystal lattice,resulting in defects that reduce the sensitivity of CPL *** study introduces the concept of chiral superposition for the first time,reporting two mixed heterostructures composed of two-dimensional（2D） chiral perovskite（R/S-MBA）2MAPb2I7（R/S）,chiral quantum dots（R/S-MBA）-CsPbBr3（R/SQD）,and chiral carbon dots（Ch-CDs）.The addition of chiral quantum dots/Ch-CDs fills the defects of the chiral perovskite films and reduces the electron-hole recombination rate in chiral hybrid perovskites,thereby significantly enhancing the circularly polarized sensitivity of the CPL *** adjusting the concentration of chiral quantum dots,controllability of spin electron transfer is achieved,which has a notable impact on circular dichroism（CD） and anisotropy factor *** anisotropy factor glhpof the mixed heterostructure R/S-R/SQD is approximately 21.58 times higher than that of single-phase chiral perovskites,and the asymmetry factor gCDincreases ***,this work opens up a new effective pathway for achieving high-sensitivity CPL detection,with promising applications in optoelectronic technologies such as spin information communication and quantum optics.

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Experimental study of lightweight aggregate concrete under multiaxial stresses

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 545-554页

作者： Han-yong liu Yu-pu SONG Structural Engineering Institute School of Civil Engineering Faculty of lnfrastructure Engineering Dalian University of Technology Dalian 116024 China

Lightweight aggregate concrete cube specimens (100 mm×100 mm×100 mm) and plate specimens (100 mm×100 mm×50 mm) were tested under biaxial compression-compression (CC) and compression-tension (CT) load combinations. For comparison, normal concrete plate specimens (100 mm×100 mm×50 mm) were tested under the same load combinations. Based on the test results, a two-level strength criterion of lightweight aggregate concrete in both octahedral stress coordinate and principal stress coordinate was suggested. The lightweight aggregate concrete cube specimens (100 mm×100 mm×100 mm) were then tested under triaxial compression-compression-compression (CCC) load combination with corresponding tests on normal concrete cube specimens (100 mm×100 mm×100 mm). The effect of intermediate principal stress on triaxial compressive strength is further examined. A "plastic flow plateau" area was apparent in principal compressive stress-strain relationships of lightweight aggregate concrete but not in normal concrete. A quadratic formula was suggested for the expression of strength criterion under triaxial compression.

关键词： Lightweight aggregate concrete Normal concrete Biaxial loads Triaxial loads Compressive strength Tensile strength Stress-strain relationships Plastic flow plateau Lode angle