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Tungsten 2025年第1期7卷 80-87页

作者： fang-Qian Wang Yin Zhang Wei-Wei Wang Mei-Qian Fu Hong-Bing Mo Wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Direct Photolithography of WO_(x)Nanoparticles for High‑Resolution Non‑Emissive Displays

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Nano-Micro Letters 2025年第3期17卷 297-309页

作者： Chang Gu Guojian Yang Wenxuan Wang Aiyan Shi Wenjuan fang Lei Qian Xiaofei Hu Ting Zhang Chaoyu Xiang Yu‑Mo Zhang Laboratory of Optoelectronic Information Technology and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Hangzhou Bay Laboratory of Advanced Nano‑Optoelectronic Materials and Devices Qianwan Institute of CNITECHNingbo 315336People’s Republic of China Smart Materials for Architecture Research Lab Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China State key Lab of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012People’s Republic of China

High-resolution non-emissive displays based on electrochromic tungsten oxides(WOx)are crucial for future near-eye virtual/augmented reality interactions,given their impressive attributes such as high environmental stability,ideal outdoor readability,and low energy ***,the limited intrinsic structure of inorganic materials has presented a significant challenge in achieving precise patterning/pixelation at the micron ***,we successfully developed the direct photolithography for WOx nanoparticles based on in situ photo-induced ligand *** strategy enabled us to achieve ultra-high resolution efficiently(line width3600 cycles),as well as promising applications in electronic logos,pixelated displays,flexible electronics,*** success and advancements presented here are expected to inspire and accelerate research and development(R&D)in high-resolution non-emissive displays and other ultra-fine micro-electronics.

关键词： Electrochromic Direct photolithography WOx nanoparticles In situ photo-induced ligand exchange High-resolution displays

The Representations of Generalized Inverses of Lower Triangular Operators

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2107-2118页

作者： Chun fang SHAO Hong ke DU Shu feng JI Jun Lian XU College of Mathematics and Information Science Shaanxi Normal University Xi'an 710062 P. R. China Department of Mathematics Ankang University Ankang 725000 P. R. China

In this note, the explicit representations of Moore-Penrose inverses of lower triangular operator matrices are established. As an application, the explicit representations of Bott-Duffin inverses of bounded linear ope... 详细信息

关键词： Moore-Penrose inverse lower triangular operator matrix Bott-Duffin inverse

Rh(Ⅱ) carbene S-H insertion into H_2S via the stepwise mechanism

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Chinese Chemical Letters 2007年第1期18卷 107-110页

作者： Zhen feng Liu Xian fang Yue Qiang Wei ke Li Han State key Laboratory of Molecular Reaction Dynamics~ Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

The mechanism of Rh（Ⅱ） carbene S-H insertion into H2S in gas phase has been studied by B3LYP functional. Calculation results showed that the Rh（Ⅱ） carbene S-H insertion into H2S took only stepwise channels and n... 详细信息

关键词： Sulfonium ylides 1,2-Hydrogen shift Density functional calculations Dirhodium(Ⅱ) carbene

Insertion of O—H Bond of Rh(Ⅱ)-methylene Carbene into Alcohols: A Stepwise Mechanism More Plausible than a Concerted Mechanism

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Chemical Research in Chinese Universities 2007年第2期23卷 221-225页

作者： LIU Zhen-feng WANG Yong YUE Xian-fang HAN ke-li State key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dcdian 116023 P. R. China

The mechanisms of insertion of O-H bond of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol were studied by using B3LYP functional both in gas phase and in CH2 C12. The formation of free alcoholic oxonium ylides is found to be impossible. Alcoholic oxonium ylide are formed as the intermediates before beth the stepwise and the concerted transition states of insertion of O-H bend of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol. With re- gard to the mechanisms of insertion of O-H of Rh（ Ⅱ ） -methylene carbene into alcohols, analysis of the energy bartiers of the two mechanisms indicate that the stepwise mechanism is more plausible than the concerted mechanism.

关键词： Oxonium ylide 1,2-Hydrogen shift Density functional calculation Dirhodium( Ⅱ ) methylene carbene

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栗属植物叶片形态特征在种间识别的研究

电子显微学报 2021年第4期40卷 432-440页

作者：顾建成聂兴华曹小艳张煜张伟伟杜兵帅郑瑞杰房克凤秦岭邢宇北京农学院植物科学技术学院北京102206 北京农学院林木分子设计育种高精尖创新中心北京102206 辽宁省经济林研究所辽宁大连116000

本研究以栗属植物6个种的成熟叶片为材料,对其叶形特征进行调查、统计和分析,并通过体式显微镜、扫描电镜和塑料包埋切片对其叶背表皮组织进行综合显微观察分析。结果表明:(1)叶片形态特征,尤其叶形和叶形指数在栗属植物种间存在显著差... 详细信息

本研究以栗属植物6个种的成熟叶片为材料,对其叶形特征进行调查、统计和分析,并通过体式显微镜、扫描电镜和塑料包埋切片对其叶背表皮组织进行综合显微观察分析。结果表明:(1)叶片形态特征,尤其叶形和叶形指数在栗属植物种间存在显著差异,可以作为不同栗属植物初步识别的重要依据之一;(2)盾状腺毛的有无在栗属植物资源描述与评价中是一个不可代替的重要指标,是识别不同栗属植物的关键组织;(3)栗属植物的腺毛组织由多细胞构成,预测其具有分泌次生代谢物的功能,在自身病虫害防治、环境适应和抗逆性等方面可能发挥着重要作用。

关键词：栗属种间识别叶形指数叶表皮腺毛

Modeling tactile perceived intensity for vibration from a coin eccentric rotating mass motor

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Science China Technological Sciences 2025年

作者： Yun fang Jingchen HUANG Yujun WU Jiaqi DONG Weichao GUO Xinjun SHENG State key Laboratory of Mechanical System and Vibration School of Mechanical Engineering Shanghai Jiao Tong University Meta Robotics Institute Shanghai Jiao Tong University

Establishing the relationship between vibrotactile parameters and perceived intensity（PI） is of great significance in the regulation of desired sensations, which contribute to haptic interfaces in practical applications. Coin eccentric rotating mass（ERM） motors are routinely utilized due to their lightweight design and efficient ability to evoke strong tactile sensations. By adjusting input voltages, ERMs can yield different stimuli, but the effects of their physical properties on PI remain ***, we developed the physical model of the ERM-skin system and optimized the parameters affecting PI. Moreover, the relationship between stimulus and perception was derived based on Fechner?s law. Three experiments were conducted on fifteen subjects（ten males and five females, aged 24.40 ± 2.87 years） to identify the vibration parameters and corresponding PI to verify the proposed PI model. ERMs in this study were attached to phantom skin/forearm with slim adhesive tape to minimize the interference. Experiment 1 performed vibration calibration with ERM attached to the skin phantom to simulate the actual configuration. Then, the relative and absolute PI of subjects on specific stimuli were acquired in Experiments 2 and *** fitting reliability of the proposed PI model was evaluated on fifteen subjects with R2of 0.73 ± 0.07 and root mean squared error（RMSE） of 1.35 ± 0.28. Overall, the proposed PI model established the quantitative relationship between stimulus parameters（vibration parameters and physical parameters） and subjective PI, which provided theoretical support for ERM optimization and vibrotactile modulation.

关键词：

An adaptive sequential experiment design method for model validation

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Chinese Journal of Aeronautics 2020年第6期33卷 1661-1672页

作者： ke fang Yuchen ZHOU Ping MA Control and Simulation Center Harbin Institute of TechnologyHarbin 150080China

Efficient experiment design is of great significance for the validation of simulation model with high nonlinearity and large input *** validation experiment raises the cost while insufficient test increases the risks of accepting an invalid *** this paper,an adaptive sequential experiment design method combining global exploration criterion and local exploitation criterion is *** exploration criterion utilizes discrepancy metric to improve the space-filling property of the design points while the exploitation criterion employs the leave one out error to discover informative *** avoid the clustering of samples in the local region,an adaptive weight updating approach is provided to maintain the balance between exploration and ***,the credibility distribution function characterizing the relationship between the input and result credibility is introduced to support the model validation experiment ***,six benchmark problems and an engineering case are applied to examine the performance of the proposed *** experiments indicate that the proposed method achieves satisfactory performance for function approximation in accuracy and convergence.

关键词： Adaptive sequential experiment design Credibility distribution function Gaussian process model Metamodeling Model validation

Aligning enhanced feature representation for generalized zero-shot learning

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Science China(Information Sciences) 2025年

作者： Zhiyu fang Xiaobin ZHU Chun YANG Hongyang ZHOU Jingyan QIN Xucheng YIN School of Computer&Communication Engineering University of Science and Technology Beijing

Abstract Constructing an effective common latent embedding by aligning the latent spaces of cross-modal variational autoencoders （VAEs） is a popular strategy for generalized zero-shot learning （GZSL）.However,due to the lack of fine-grained instance-wise annotations,existing VAE methods can easily suffer from the posterior collapse *** this paper,we propose an innovative asymmetric VAE network by aligning enhanced feature representation （AEFR） for *** from general VAE structures,we designed two asymmetric encoders for visual and semantic observations and one decoder for visual ***,we propose a simple yet effective gated attention mechanism （GAM） in the visual encoder for enhancing the information interaction between observations and latent variables,alleviating the possible posterior collapse problem *** addition,we propose a novel distributional decoupling-based contrastive learning （D2-CL） to guide learning classification-relevant information while aligning the representations at the taxonomy level in the latent representation *** experiments on publicly available datasets demonstrate the state-of-the-art performance of our *** source code is available at https://***/seeyourmind/AEFR.

关键词：

Non-equilibrium turbulent phenomena in transitional flat plate boundary-layer flows

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Applied Mathematics and Mechanics(English Edition) 2021年第4期42卷 567-582页

作者： feng LIU Le fang Jian fang School of Energy and Power Engineering North University of ChinaTaiyuan 030051China Laboratory of Mathematics and Physics Ecole Centrale de P′ekinBeihang UniversityBeijing 100191China Scientific Computing Department STFC Daresbury LaboratoryWarrington WA44ADU.K.

Many recent laboratory experiments and numerical simulations support a non-equilibrium dissipation scaling in decaying turbulence before it reaches an equilibrium *** analyzing a direct numerical simulation(DNS)database of a transitional boundary-layer flow,we show that the transition region and the non-equilibrium turbulence region,which are located in different streamwise zones,present different non-equilibrium ***,in the wall-normal direction,the viscous sublayer,log layer,and outer layer show different non-equilibrium phenomena which differ from those in grid-generated turbulence and transitional channel *** findings are expected to shed light on the modelling of various types of non-equilibrium turbulent flows.

关键词： non-equilibrium turbulence flat plate boundary layer turbulence model