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Effects of different types of slow-and controlled-release fertilizers on rice yield

Journal of Integrative Agriculture 2021年第6期20卷 1503-1514页

作者： WU Qiong WANG Yu-hui DING Yan-feng TAO wei-ke GAO Shen LI Quan-xin LI wei-wei LIU Zheng-hui LI gang-hua Jiangsu Collaborative Innovation Center for Modern Crop Production/National Engineering and Technology Center for Information Agricultrue/Key Laboratory of Crop Physiology and Ecology in Southern China Nanjing Agricultural UniversityNanjing 210095P.R.China

This experiment explored the effects of single application of seven types of slow-and controlled-release fertilizers on rice yield and various population *** on a study of the nitrogen(N)release characteristics of these fertilizers,pot experiments were conducted in 2018 and 2019 with split fertilization(CK,urea applied split equally at basal and panicle initiation stages,respectively)as control,which assessed the effects on SPAD value,yield and yield components,dynamic changes of rice tillers and dry matter *** results showed that the N release characteristics of different types of slow-and controlled-release fertilizers were significantly ***-coated urea(PCU)showed a controlledrelease mode and provided sustained release throughout the whole growth ***-coated urea(SCU)exhibited a slow-release mode,providing insufficient release at the middle and late *** inhibitor urea(AHA)and ureaformaldehyde(UF)yielded a rapid-release mode,with an explosive N release at the early stage and no release at the middle and late *** results showed that PCU delayed the peak seedling *** with CK,dry matter accumulation and SPAD showed no significant differences,and due to the continuous release of N throughout the growth stages,rice yield,spikelets per panicle,seed setting rate,and 1000-grain weight were all *** to the lack of N supply at the late stage and the low number of spikelets,SCU led to a reduction of rice yield,which is nevertheless not statistically *** and UF were susceptible to environmental factors and had varying effects on rice *** results of this experiment indicated that given a fixed amount of N applied in a pot,the stronger the N supply capacity and the longer the effective duration time of the fertilizer,the higher the dry matter accumulation at the late growth stage,and the higher the rice yield.

关键词： slow-and controlled-release fertilizers fertilizer types rice yield fertilizer release characteristics

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A six-variable quasi-3D isogeometric approach for free vibration of functionally graded graphene origami-enabled auxetic metamaterial plates submerged in a fluid medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 157-176页

作者： wei CHEN Zhihong TANG Yufen LIAO Linxin PENG College of Civil Engineering University of South China College of Civil Engineering and Architecture Guangxi University Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education Guangxi University

This paper presents, for the first time, an effective numerical approach based on the isogeometric analysis(IGA) and the six-variable quasi-three dimensional(3D)higher-order shear deformation theory(HSDT) to study the free vibration characteristics of functionally-graded(FG) graphene origami(GOri)-enabled auxetic metamaterial(GOEAM) plates submerged in a fluid medium. The plate theory incorporates the thickness stretching and the effects of transverse shear deformation without using any shear correction factors. The velocity potential function and Bernoulli's equation are used to derive the hydrodynamic pressure acting on the plate surface. Both horizontally and vertically immersed plate configurations are considered here in the form of inertia *** plates are composed of multilayer GOEAMs, with the GOri content varying through the plate's thickness in a layer-wise manner. This design results in graded auxetic *** material properties are evaluated by mixing rules and a genetic programming(GP)-assisted micromechanical model. The governing equations of motion for the FG-GOEAM plates immersed in a fluid medium are derived by Hamilton's principle. After validating the convergence and accuracy of the present model, a comprehensive parametric study is carried out to examine the effects of the GOri content, GOri distribution pattern, GOri folding degree, fluid level, immersed depth, and geometric parameter on the natural frequencies of the FG-GOEAM plates. The results show that the natural frequencies for the four GOri distribution patterns increase with the increase in the layer number when the lay number is fewer than 10, and then stabilize after the layer number reaches ***, in general, the natural frequency of the FG-GOEAM plate in a vacuum or fluid increases when the GOri content increases, while decreases when the GOri folding degree increases. Some additional findings related to the numerical results are presented in the conclusions. It is belie

关键词： Equations of motion

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Bounds of Deviation for Branching Chains in Random Environments

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Acta Mathematica Sinica,English Series 2011年第5期27卷 897-904页

作者： wei gang WANG School of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 P. R. China

We consider non-extinct branching processes in general random environments. Under the condition of means and second moments of each generation being bounded, we give the upper bounds and lower bounds for some form dev... 详细信息

关键词： Branching processes in random environments deviation, upper bound, lower bound

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High-dimensional large-scale mixed-type data imputation under missing at random

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Science China Mathematics 2025年

作者： wei Liu Guizhen Li Ling Zhou Lan Luo School of Mathematics Sichuan University Center of Statistical Research and School of Statistics Southwestern University of Finance and Economics Department of Statistics and Actuarial Science University of Iowa

Missingness in mixed-type variables is commonly encountered in a variety of areas. The requirement of complete observations necessities data imputation when a moderate or large proportion of data is ***, inappropriate imputation would downgrade the performance of machine learning algorithms, leading to bad predictions and unreliable statistical inference. For high-dimensional large-scale mixed-type missing data, we develop a computationally efficient imputation method, missing value imputation via generalized factor models（MIG）, under missing at random. The proposed MIG method allows missing variables to be of different types,including continuous, binary, and count variables, and are scalable to both data size n and variable dimension p while existing imputation methods rely on restrictive assumptions such as the same type of missing variables,the low dimensionality of variables, and a limited sample size. We explicitly show that the imputation error of the proposed MIG method diminishes to zero with the rate Op(max{n-1/2, p-1/2}) as both n and p tend to infinity. Five real datasets demonstrate the superior empirical performance of the proposed MIG method over existing methods that the average normalized absolute imputation error is reduced by 5.3%–34.1%.

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Evolution and organic geochemical significance of bicyclic sesquiterpanes in pyrolysis simulation experiments on immature organic-rich mudstone

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Petroleum Science 2019年第3期16卷 502-512页

作者： gang Yan Yao-hui Xu Yan Liu Peng-Hai Tang wei-Bin Liu Key Laboratory of Exploration Technologies for Oil and Gas Resources (Yangtze University) Ministry of Education Wuhan 430100 Hubei China College of Resources and Environment Yangtze University Wuhan 430100 HubeiChina Institute of Mud Logging Technology and Engineering (Yangtze University) Jingzhou 434023 HubeiChina Oil and Gas Survey China Geological Survey Beijing 100029China

Sesquiterpanes are ubiquitous components of crude oils and ancient *** saturated hydrocarbons from simulated pyrolysis experiments on immature organic-rich mudstone collected from the Lower Cretaceous Hesigewula Sag were analyzed by gas chromatography-mass spectrometry(GC-MS).C14 bicyclic sesquiterpanes,namely,8β(H)-drimane,8β(H)-homodrimane,and 8 a(H)-homodrimane were detected and identified on basis of their diagnostic fragment ions(m/z123,179,193,and 207),and previously published mass spectra data,and these bicyclic sesquiterpanes presented relatively regular characteristics in their thermal *** ratios 8β(H)-drimane/8β(H)-homodrimane,8β(H)-homodrimane/8 a(H)-homodrimane,and 8β(H)-drimane/8 a(H)-homodrimane all show a clear upward trend with increasing temperature below the temperature turning ***,all these ratios can be used as evolution indexes of source rocks in the immature-lowmaturity ***,the last two ratios may be more suitable than the first ratio as valid parameters for measuring the extent of thermal evolution of organic matter in the immature-low-maturity stage because their change amplitude with increasing temperature is more obvious.

关键词： Immature-low-maturity stage Simulated pyrolysis experiment Bicyclic sesquiterpanes Thermal evolution Maturity indicators

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The deformation and failure mechanism of cylindrical shell and square plate with pre-formed holes under blast loading

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Defence Technology（防务技术） 2021年第4期17卷 1143-1159页

作者： wei Li Peng Wang Gao-peng Feng Yong-gang Lu Jun-zheng Yue hui-min Li Institute of System Engineering CAEPMianyang 621900SichuanChina Institute of Mechanics Chinese Academy of ScienceBeijing 100190China

The deformation and failure mechanism of cylindrical shells and square plate with pre-formed holes under blast loading were investigated numerically by employing the Ansys 17.0 and Ls-Dyna *** calibrate the numerical model,the experiments of square plates with pre-formed circle holes were modeled and the numerical results have a good agreement with the experiment *** calibrated numerical model was used to study the deformation and failure mechanism of cylindrical shells with pre-formed circle holes subjected to blast *** structure response and stress field changing process has been divided into four specific stages and the deformation mechanism has been discussed *** local and global deformation curves,degree of damage,change of stress status and failure modes of cylindrical shell and square plate with pre-formed circular holes are obtained,compared and analyzed,it can be concluded as:(1)The transition of tensile stress fields is due to the geometrical characteristic of pre-formed holes and cylindrical shell with arch configuration;(2)The existence of preformed holes not only lead to the increasing of stress concentration around the holes,but also release the stress concentration during whole response process;(3)There are three and two kinds of failure modes for square plate and cylindrical shell with pre-formed holes,*** the standoff distance has a key influence on the forming location of the crack initiating point and the locus of crack propagation;(4)The square plate with pre-formed holes has a better performance than cylindrical shell on blast-resistant capability at a smaller standoff distance,while the influence of pre-formed holes on the reduction of blast-resistant capability of square plate is bigger than that of cylindrical shell.

关键词： Pre-formed holes Cylindrical shell and square plate Deformation mechanism Failure mechanism

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Unraveling the catalytically active phase of carbon dioxide hydrogenation to methanol on Zn/Cu alloy: Single atom versus small cluster

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Journal of Energy Chemistry 2021年第10期30卷 582-593,I0015页

作者： Xiao-Kuan Wu hui-Min Yan wei Zhang Jie Zhang Guang-Jie Xia Yang-gang Wang Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and TechnologyShenzhen 518055GuangdongChina State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Methanol synthesis from CO_(2)hydrogenation catalyzed by Zn/Cu alloy has been widely studied,but there is still debate on its catalytic active phase and whether the Zn can be oxidized during the reaction *** is more,as Zn atoms could locate on Zn/Cu alloy surface in forms of both single atom and cluster,how Zn surface distribution affects catalytic activity is still not *** this work,we performed a systematic theoretical study to compare the mechanistic natures and catalytic pathways between Zn single atom and small cluster on catalyst surface,where the surface oxidation was shown to play the critical *** surface oxidation,the Zn single atom/Cu is more active than the Zn small cluster/Cu,but its surface oxidation is difficult to take ***,after the easy surface oxidation by CO_(2)decomposition,the oxidized Zn small cluster/Cu becomes much more active,which even exceeds the hardlyoxidized Zn single atom/Cu to become the active *** analyses show this dramatic promotion of surface oxidation can be ascribed to the following factors:i)The O from surface oxidation could preferably occupy the strongest binding sites on the center of Zn *** makes the O intermediates bind at the Zn/Cu interface,preventing their too tight binding for further hydrogenation;ii)The higher positive charge and work function on the oxidized surface could also promote the hydrogenation of O *** work provided one more example that under certain condition,the metal cluster can be more active than the single atom in heterogeneous catalysis.

关键词： CO_(2)hydrogenation Surface oxidation Zn/Cu alloy Catalytically active phase

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Pre-existing chromatin accessibility of switchable repressive compartment delineates cell plasticity

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National Science Review 2022年第6期9卷 100-113页

作者： Xiaolong Ma Xuan Cao Linying Zhu Ying Li Xuelong Wang Baihua Wu gang wei Lijian hui State Key Laboratory of Cell Biology Shanghai Institute of Biochemistry and Cell Biology Center for Excellence in Molecular Cell Science Chinese Academy of Sciences School of Life Science and Technology Shanghai Tech University School of Life Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences University of Chinese Academy of Sciences Bio-Research Innovation Center Shanghai Institute of Biochemistry and Cell Biology Institute for Stem Cell and Regeneration Chinese Academy of Sciences CAS Key Laboratory of Computational Biology Shanghai Institute of Nutrition and Health Chinese Academy of SciencesUniversity of Chinese Academy of Sciences

Cell plasticity endows differentiated cells with competence to be reprogrammed to other lineages. Although extrinsic factors driving cell-identity conversion have been extensively characterized, it remains elusive which intrinsic epigenetic attributes, including high-order chromatin organization, delineate cell *** analysing the transcription-factor-induced transdifferentiation from fibroblasts to hepatocytes, we uncovered contiguous compartment-switchable regions(CSRs) as a unique chromatin unit. Specifically,compartment B-to-A CSRs, enriched with hepatic genes, possessed a mosaic status of inactive chromatin and pre-existing and continuous accessibility in fibroblasts. Pre-existing accessibility enhanced the binding of inducible factor Foxa3, which triggered epigenetic activation and chromatin interaction as well as hepatic gene expression. Notably, these changes were restrained within B-to-A CSR boundaries that were defined by CTCF occupancy. Moreover, such chromatin organization and mosaic status were detectable in different cell types and involved in multiple reprogramming processes, suggesting an intrinsic chromatin attribute in understanding cell plasticity.

关键词： cell plasticity intrinsic properties compartment-switchable regions mosaic status pre-existing accessibility hepatic transdifferentiation

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Molecular Structure Tailoring of Organic Spacers for High‑Performance Ruddlesden–Popper Perovskite Solar Cells

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Nano-Micro Letters 2025年第2期17卷 314-357页

作者： Pengyun Liu Xuejin Li Tonghui Cai wei Xing Naitao Yang Hamidreza Arandiyan Zongping Shao Shaobin Wang Shaomin Liu School of Materials Science and Engineering State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(East China)Qingdao 266580People’s Republic of China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049People’s Republic of China Centre for Applied Materials and Industrial Chemistry(CAMIC) School of ScienceRMIT UniversityMelbourneVic 3000Australia WA School of Mines:Minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia School of Chemical Engineering The University of AdelaideAdelaideSA 5005Australia School of Engineering Great Bay UniversityDongguan 523000People’s Republic of China

Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(PSC)***,two-dimensional(2D)or quasi-2D RP PSCs are encountered with some challenges of the large exciton binding energy,blocked charge transport and poor film quality,which restrict their photovoltaic ***,these issues can be readily resolved by rationally designing spacer cations of *** review mainly focuses on how to design the molecular structures of organic spacers and aims to endow RPPs with outstanding photovoltaic *** firstly elucidated the important roles of organic spacers in impacting crystallization kinetics,charge transporting ability and stability of *** we brought three aspects to attention for designing organic ***,we presented the specific molecular structure design strategies for organic spacers of RPPs aiming to improve photovoltaic performance of RP *** proposed strategies in this review will provide new avenues to develop novel organic spacers for RPPs and advance the development of RPP photovoltaic technology for future applications.

关键词： Ruddlesden-Popper perovskites Low-dimensional perovskite solar cells Organic spacers Molecular structure Design strategies

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In situ irradiated X-ray photoelectron spectroscopy on Ag-WS2 heterostructure for hydrogen production enhancement

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Journal of Materiomics 2021年第2期7卷 320-327页

作者： Shen-wei Bai hui Mei wei-zhao Huang Ming-gang Zhang Lai-fei Cheng Science and Technology on Thermostructural Composite Materials Laboratory School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi710072PR China School of Science Xi’an Polytechnic UniversityXi’anShaanxi710048PR China

The hot electron transition of noble materials to catalysis accelerated by localized surface plasmon resonances(LSPRs)was detected by in situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)in this *** paper synthesized an Ag Nanowire(AgNW)@WS2 core-shell structure,with an ultra-thin shell of WS_(2)(3-7 nm),and characterized its photocatalytic *** AgNW@WS_(2) core-shell structure exhibited different surface-enhanced Raman spectroscopy(SERS)effects by changing shell thickness,indicating that the effect of AgNW could be controlled by WS2 ***,the hydrogen production of AgNW@WS2 could reach to 356%of that of pure *** hot electrons arising from the LSPRs effect broke through the Schottky barrier between WS_(2) and AgNW and transferred to the WS2 shell,whose photocatalytic effect was thus *** addition,when the LSPRs effect was intensified by reducing the shell thickness,the hot electron transition of noble materials to catalysis was accelerated.

关键词： Hot electron transfer Localized surface plasmon resonances(LSPRs) Photocatalytic hydrogen production Heterostructure

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