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Oxygen modified CoP2 supported palladium nanoparticles as highly efficient catalyst for hydrolysis of ammonia borane

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Nano Research 2022年第4期15卷 3034-3041页

作者： Leijie Zhang Jian Ye yi tu Qingyu Wang Haibin Pan Lihui Wu Xusheng Zheng Junfa Zhu National Synchrotron Radiation Laboratory Department of Chemical Physics and Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei 230029China School of Science Anhui Agricultural UniversityHefei 230036China

Ammonia borane(AB)is regarded as a promising chemical hydrogen-storage material due to its high hydrogen content,nontoxicity,and long-term stability under ambient ***,constructing advanced catalysts to further promote the hydrogen production still remains a challenge for the hydrolysis of ***,we report a novel oxygen modified CoP_(2)(O-CoP_(2))material with dispersed palladium nanoparticles(Pd NPs)as a highly efficient and sustainable catalyst for AB *** modification of oxygen could optimize the catalytic synergy effect between CoP_(2)and Pd NPs,achieving enhanced catalytic activity with a turnover frequency(TOF)number of 532 min^(-1)and an activation energy(E_(a))value of 16.79 kJ·mol^(-1).Meanwhile,reaction kinetic experiments prove that the activation of water is the rate-determining step(RDS).The water activation mechanism is revealed by quasi in-situ X-ray photoelectron spectroscopy(XPS)and in-situ X-ray absorption fine structure(XAFS)*** activation of water leads to the production of-H and-OH groups,which are further adsorbed on the oxygen atoms in P-O bond and Pd atoms,*** addition,density functional theory(DFT)calculations indicate that the introduced oxygen facilitates the adsorption and activation of water *** novel modulation strategy successfully sheds new light on the development of advanced catalysts for hydrolysis of AB and beyond.

关键词： Pd-based catalysis ammonia borane hydrolysis water activation quasi in-situ X-ray photoelectron spectroscopy density functional theory(DFT)calculations

Pumpability of Manufactured Sand Self-compacting Concrete

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1382-1390页

作者： LI Huajian HUANG Fali tu Haifeng SUN Deyi WANG Zhen yi Zhonglai YANG Zhiqiang XIE Yongjiang Railway Engineering Research Institute China Academy of Railway Science Corporation LimitedBeijing 100081China School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China China Railway Engineering Design and Consulting Group Co. Ltd Beijing 100055China

By the addition of superplasticizer and air entraining agent,manufactured sand selfcompacting concrete(MS SCC)with slump flow varying from 500 to 700 mm and air content varying from 2.0%to 9.0%were prepared and the pumpability of MS SCC was studied by a sliding pipe rheometer(Sliper).According to the Kaplan’s model,the initial pump pressure and the pump resistance of MS SCC were ***,rheological properties including the yield stress and the plastic viscosity of MS SCC were measured by a *** experimental results show that the increase of slump flow contributes to a higher pumpability and a proper air content,i e,6%is beneficial for the pumpability of MS *** to the existence of stone powder and stronger angularity of MS,the initial pump pressure of MS SCC is only about 60%-88%that of river sand(RS)SCC with the same slump flow and air content,indicating that MS SCC possesses a higher pumpability than RS SCC.

关键词： manufactured sand self-compacting concrete pumpability sliding pipe rheometer rheology

Recent advances and application in whole-genome multiple displacement amplification

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Quantitative Biology 2020年第4期8卷 279-294页

作者： Naiyun Long yi Qiao Zheyun Xu Jing tu Zuhong Lu State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China

Background:The extremely small amount of DNA in a cell makes it difficult to study the whole genome of single cells,so whole-genome amplification(WGA)is necessary to increase the DNA amount and enable downstream *** displacement amplification(MDA)is the most widely used WGA ***:Compared with amplification methods based on PCR and other methods,MDA renders high-quality DNA products and better genome coverage by using phi29 DNA ***,recently developed advanced MDA technologies such as microreactor MDA,emulsion MDA,and micro-channel MDA have improved amplification ***,the development of other novel methods such as TruePrime WGA allows for amplification without ***:Here,we reviewed a selection of recently developed MDA methods,their advantages over other WGA methods,and improved MDA-based technologies,followed by a discussion of future *** the continuous development of MDA and the successive update of detection technologies,MDA will be applied in increasingly more fields and provide a solid foundation for scientific research.

关键词： whole genome amplification multiple displacement amplification improved MDA-based approaches

ReLoc:Indoor Visual Localization with Hierarchical Sitemap and View Synthesis

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Journal of Computer Science & Technology 2021年第3期36卷 494-507页

作者： Hui-Xuan Wang Jing-Liang Peng Shi-yi Lu Xin Cao Xue-ying Qin Chang-He tu School of Computer Science and Technology Shandong UniversityQingdao 266237China School of Information Science and Engineering University of JinanJinan 250022China School of Software Shandong UniversityJinan 250101China

Indoor visual localization,i.e.,6 Degree-of-Freedom camera pose estimation for a query image with respect to a known scene,is gaining increased attention driven by rapid progress of applications such as robotics and augmented ***,drastic visual discrepancies between an onsite query image and prerecorded indoor images cast a significant challenge for visual *** this paper,based on the key observation of the constant existence of planar surfaces such as floors or walls in indoor scenes,we propose a novel system incorporating geometric information to address issues using only pixelated *** the system implementation,we contribute a hierarchical structure consisting of pre-scanned images and point cloud,as well as a distilled representation of the planar-element layout extracted from the original dataset.A view synthesis procedure is designed to generate synthetic images as complementary to that of a sparsely sampled ***,a global image descriptor based on the image statistic modality,called block mean,variance,and color(BMVC),was employed to speed up the candidate pose identification incorporated with a traditional convolutional neural network(CNN)*** results on a popular benchmark demonstrate that the proposed method outperforms the state-of-the-art approaches in terms of visual localization validity and accuracy.

关键词： visual localization planar surface statistic information view synthesis

Numerical simulation of a direct internal reforming solid oxide fuel cell using computational fluid dynamics method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 961-969页

作者： Jun LI ying-wei KANG Guang-yi CAO Xin-jian ZHU Heng-yong tu Jian LI Institute of Fuel Cell Department of Automalion Shanghai Jiao Tong University Shanghai 200240 China College of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

A detailed mathematical model of a direct internal reforming solid oxide fuel cell(DIR-SOFC) incorporating with simulation of chemical and physical processes in the fuel cell is presented. The model is developed based on the reforming and electrochemical reaction mechanisms,mass and energy conservation,and heat transfer. A computational fluid dynamics(CFD) method is used for solving the complicated multiple partial differential equations(PDEs) to obtain the numerical approximations. The resulting distributions of chemical species concentrations,temperature and current density in a cross-flow DIR-SOFC are given and analyzed in detail. Further,the influence between distributions of chemical species concentrations,temperature and current density during the simulation is illustrated and discussed. The heat and mass transfer,and the kinetics of reforming and electrochemical reactions have significant effects on the parameter distributions within the cell. The results show the particular characteristics of the DIR-SOFC among fuel cells,and can aid in stack design and control.

关键词： Direct internal reforming (DIR) Solid oxide fuel cell (SOFC) Computational fluid dynamics (CFD) Numerical simulation

Multistage Microstructured Ionic Skin for Real-Time Vital Signs Monitoring and Human-Machine Interaction

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Energy & Environmental Materials 2024年第6期7卷 218-229页

作者： Xueke Wang Jinyu Zi yi Chen Qiang Wu Zhimin Xiang Yongqiang tu Peng Yang Yanfen Wan National Center for International Research on Photoelectric and Energy Materials Yunnan Key Laboratory for Micro/Nano Materials&TechnologyYunnan Key Laboratory of Electromagnetic Materials and DevicesSchool of Materials and EnergyYunnan UniversityKunming 650091China

Skin-like electronics research aiming to mimic even surpass human-like specific tactile cognition by operating perception-to-cognition-to-feedback of stimulus to build intelligent cognition systems for certain imperceptible or inappreciable signals was so ***,we constructed an all-in-one tri-modal pressure sensing wearable device to address the issue of power supply by integrating multistage microstructured ionic skin(MM i-skin)and thermoelectric self-power staffs,which exhibits high sensitivity *** MM i-skin with multi-stage“interlocked”configurations achieved precise recognition of subtle signals,where the sensitivity reached up to 3.95 kPa^(−1),as well as response time of 46 ms,cyclic stability(over 1500 cycles),a wide detection range of 0–200 ***,we developed the thermoelectricity nanogenerator,piezoelectricity nanogenerator,and piezocapacitive sensing as an integrated tri-modal pressure sensing,denoted as P-iskin,T-iskin,and C-iskin,*** multifunctional ionic skin enables real-time monitoring of weak body signals,rehab guidance,and robotic motion recognition,demonstrating potential for Internet of things(IoT)applications involving the artificial intelligence-motivated sapiential healthcare Internet(SHI)and widely distributed human-machine interaction(HMI).

关键词： bio-template method integrated device ionic skin skin-like microstructure tri-modal pressure sensing

Cosmological scenario based on particle creation and holographic equipartition

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Chinese Physics C 2020年第6期44卷 162-168页

作者： Fei-Quan tu yi-Xin Chen Qi-Hong Huang School of Physics and Electronic Science Zunyi Normal UniversityZunyi 563006China Zhejiang Institute of Modern Physics Zhejiang UniversityHangzhou 310027China

We propose a cosmological scenario that describes the evolution of the universe based on particle creation and holographic equipartition. The model attempts to solve the inflation of the early universe and the accelerated expansion of the present universe without introducing the dark energy from the thermodynamical *** the evolution of the universe, we assume that the universe consistently creates particles, and that the holographic equipartition is always satisfied. Further, we set the creation rate of particles proportional to H^2 in the early universe and to H in the present and late universe, where H depicts the Hubble parameter. Consequently, we obtain the solutions a(t) ∝ e^αt/3 and a(t) ∝ t^1/2 for the early universe and solutions a(t) ∝ t^δ and a(t) ∝ e^Ht for the present and late universe, respectively, where α and δ are the parameters. Finally, we obtain and analyze two important thermodynamic properties for the present model.

关键词： particle creation holographic equipartition non-equilibrium thermodynamics

Evaluation of the Global and Regional Assimilation and Prediction System for Predicting Sea Fog over the South China Sea

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Advances in Atmospheric Sciences 2019年第6期36卷 623-642页

作者： Huijun HUANG Bin HUANG Li yi Chunxia LIU Jing tu Guanhuan WEN Weikang MAO Institute of Tropical and Marine Meteorology China Meteorological Administration National Meteorological Centre Ocean University of China Guangdong Meteorological Observatory

In the South China Sea, sea fog brings severe disasters every year, but forecasters have yet to implement an effective seafog forecast. To address this issue, we test a liquid-water-content-only(LWC-only) operational sea-fog prediction method based on a regional mesoscale numerical model with a horizontal resolution of about 3 km, the Global and Regional Assimilation and Prediction System(GRAPES), hereafter GRAPES-3 km. GRAPES-3 km models the LWC over the sea, from which we infer the visibility that is then used to identify fog. We test the GRAPES-3 km here against measurements in 2016 and 2017 from coastal-station observations, as well as from buoy data, data from the Integrated Observation Platform for Marine Meteorology, and retrieved fog and cloud patterns from Himawari-8 satellite data. For two cases that we examine in detail, the forecast region of sea fog overlaps well with the multi-observational data within 72 h. Considering forecasting for0–24 h, GRAPES-3 km has a 2-year-average equitable threat score(ETS) of 0.20 and a Heidke skill score(HSS) of 0.335,which is about 5.6%(ETS) and 6.4%(HSS) better than our previous method(GRAPES-MOS). Moreover, the stations near the particularly foggy region around the Leizhou Peninsula have relatively high forecast scores compared to other sea ***, the results show that GRAPES-3 km can roughly predict the formation, evolution, and dissipation of sea fog on the southern China coast.

关键词： sea fog operational GRAPES model southern China coast forecast evaluation

A Spatial Cluster Analysis of Heavy Rains in China

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Atmospheric and Oceanic Science Letters 2011年第1期4卷 36-40页

作者： tu Kai YAN Zhong-Wei WANG yi Key Laboratory of Regional Climate-Environment for East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China National Meteorological Center Chinese Meteorological Administration Beijing 100081 China

Clustered heavy rains （CHRs） defined using hierarchical cluster analysis based on daily observations of precipitation in China during 1960-2008 are investi- gated in this paper. The geographical pattern of CHRs in China shows three high-frequency centers--South China, the Yangtze River basin, and part of North China around the Bohai Sea. CHRs occur most frequently in South China with a mean annual frequency of 6.8 （a total of 334 times during 1960-2008）. June has the highest monthly frequency （2.2 times/month with a total of 108 times dur- ing 1960-2008）, partly in association with the Meiyu phenomenon in the Yangtze River basin. Within the past 50 years, the frequency of CHRs in China has increased significantly from 13.5 to 17.3 times per year, which is approximately 28%. In the 1990s, the frequency of CHRs often reached 19.1 times per year. The geographical extent of CHR has expanded slightly by 0.5 stations, and its average daily rainfall intensity has increased by 3.7 mm d-1. The contribution of CHRs to total rainfall amount and the frequency of daily precipitation have increased by 63.1% and 22.7%, respectively, partly due to a significant decrease in light rains. In drying regions of North and Northeast China, the amounts of minimal CHRs have had no significant trend in recent years, probably due to warming in these arid regions enhancing atmospheric conveetivity at individual stations.

关键词： cluster analysis heavy rain cIimate extremes geographical correlation.