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Chinese Journal of Chemical Engineering 2022年第10期50卷 347-351页

作者： zhaoyang yu Jing Li Xianren Zhang State Key Laboratory of OrganicInorganic Composites Beijing University of Chemical TechnologyBeijing 100029China College of Biomedical Engineering&the Key Laboratory for Medical Functional Nanomaterials Jining Medical UniversityJining 272067China

Cavitation in water generally takes place at much lower negative pressure than predicted from theories.In this work,we try to stress the discrepancy from the influence of the dissolved gas on cavitation nucleation.By combining molecular dynamics simulation and thermodynamic analysis,we evaluated the lowering of surface tension as a function of density of gas molecules in gas clusters formed in aqueous solution.We found that the obtained surface tension of small gas clusters is much more substantially reduced than expected.The surface tension lowering and the non-ideality of gas molecules in the clusters are then taken into account in determining the nucleation of cavitation,and as a consequence,the required negative pressure for cavitation becomes comparable to experimental values.Thus,we give an alternative explanation for the discrepancy of cavitation pressure between experiment and theory,i.e.,it is the substantially reduced surface tension for small gas nuclei,which have not been taken into account in theory,along with the ideal gas approxiamtion that induce its deviation from the experimental values.

关键词： Cavitation Dissolved gas Thermodynamics Molecular simulation Surface tension

An Investigation on the Visible Characteristics of Four Caesalpiniaceae Wood Species in Gabon

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Journal of Renewable Materials 2022年第5期10卷 1365-1379页

作者： zhaoyang yu Jinbo Hu yuan Liu Shanshan Chang Ting Li Gonggang Liu Qiongtao Huang Jianying yuan College of Materials Science and Engineering Central South University of Forestry and TechnologyChangsha410004China Hunan Taohuajiang Bamboo Science&Technology Co. Ltd.Yiyang413400China Yihua Lifestyle Technology Co. Ltd.Shantou515834China Guangxi Gaofeng State Owered Forest Farm Nanning530022China

Color,whiteness and glossiness of four caesalpiniaceae wood species were characterized by quantitative measurements and image analysis,i.e.,which were respectively Berlinia bracteosa Benth.,Monopetalanthus heitzii Pellegr.,Distemonanthus benthamianus and Erythrophleum ivorense A.Chev.The color of four wood species was evaluated to be consistent by the CIELab and CIE1931 color system.The boards of B.bracteosa,M.heitzii and E.ivorense was divided into dark color.The wood color of B.bracteosa had the highest red to green hue,while the wood appearance of D.benthamianus had the brightest and yellowest color within the four wood species.The whiteness of D.benthamianus was significantly higher than the other three wood species,namely tangential section 21.9%and radial section 22.2%.Hence,the color of the four species varied significantly,which was closely related to internal constituents of wood materials.M.heitzii wood had the highest surface glossiness on both tangential and radial section surfaces.The surface glossiness was highly related to the wood microstructure,especially with the pore and groove structure.This study of the visible characteristics provided the indicated knowledge for the application of the four wood species in wood industry.

关键词： Caesalpiniaceae visible characteristic wood color glossiness whiteness

Optimization of Photo-Fenton Catalyst Preparation Based Bamboo Carbon Fiber by Response Surface Methodology

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Journal of Renewable Materials 2023年第1期11卷 147-165页

作者： Yizhang Wang zhaoyang yu Jinbo Hu Shanshan Chang yuan Liu Ting Li Gonggang Liu Xiaodong(Alice)Wang College of Materials Science and Engineering Central South University of Forestry and TechnologyChangsha410004China Hunan Taohuajiang Bamboo Science&Technology Co. Ltd.Yiyang413400China Department of Wood and Forest Sciences Laval UniversityQuebecG1V 0A6Canada

In this paper,the residue from bamboo factory has been used to design photo-Fenton catalyst,which has the advantages of low cost and magnetic recycling.The photo-Fenton catalytic performance of the biocarbon-based catalyst was excellent and its optimal preparation process was also explored by response surface methodology.First,bamboo-carbon fiber was selected as the photo-Fenton catalyst carrier.Subsequently,the surface of the car-bon fiber was modified,with which dopamine,nano-Fe_(3)O_(4) and nano-TiO_(2) were successively loaded by hydro-thermal method.After the single factor tests,four factors including dopamine concentration,ferric chloride mass,P25 titanium dioxide mass and liquid-solid ratio were selected as the characteristic values.The degradation efficiency of photo-Fenton catalyst to methylene blue(MB)solution was treated as the response value.After the analysis of the response surface optimization,it was shown that the significance sequence of the selected 4 factors in terms of the MB degradation efficiency was arranged as follows:dopamine concentration>liquid-solid ratio>P25 titanium dioxide quality>ferric chloride quality.The optimal process parameters of fiber-carbon catalyst were affirmed as follows:the 1.7 mg/mL concentration of dopamine,the 1.2 g mass of ferric chloride,the 0.2 g mass of P25 titanium dioxide and the liquid-solid ratio of 170 mL/g.The experiment-measured average MB degra-dation efficiency performed by the optimized catalyst was 99.3%,which was nearly similar to the model-predicted value of 98.9%.It showed that the prediction model and response surface model were accurate and reliable.The results from response surface optimization could provide a good reference to design bamboo-based Fenton-like catalyst with excellent catalytic performance.

关键词： Photo-fenton catalysis bamboo fiber carbon fiber response surface optimization methylene blue

Experimental determination of restitution coefficient of garlic bulb based on high-speed photography

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 81-90页

作者： zhaoyang yu Zhichao Hu Baoliang Peng Fengwei Gu Ling Yang Mingjin Yang College of Engineering and Technology Southwest UniversityChongqing 400715China Nanjing Institute of Agricultural Mechanization Ministry of Agriculture and Rural AffairsNanjing 210014China

Restitution coefficient(RC)of garlic bulb is an important mechanical property that is required to establish the kinematics model of bulb collision and research the damage mechanism of bulb collision.In this study,kinetic equations of bulb collision were established based on Hertz's contact theory.The kinematics characteristics,elastoplastic deformation and contact damage during bulb collision were analyzed by using high-speed photography.The effects of bulb mass,moisture content,collision material,material thickness and release height on the RC were investigated by mixed orthogonal experiments and single-factor experiments.The results showed that the movement of bulb in the compression stage was translation,and the movement in the rebound stage was translation and rotation.During collision,the larger the rotational angular velocity of the bulb was,the smaller the measured RC would be.The contact damage of bulb included internal damage of the tissue,epidermis stretch and tear.The significance of effects of factors on RC decreased with the following sequence:collision material,release height,material thickness,bulb mass,and moisture content.Collision material,release height,material thickness,and bulb mass were significant factors.The RC between the bulb and Q235,nylon,and rubber decreased sequentially.The RC decreased with the increase of release height and bulb mass.The RC increased with the increase of material thickness of Q235,while it decreased with the increase of material thickness of rubber or Nylon.The determination coefficients of the regression equations between the significant factors and the RC were all greater than 0.96.The results will be helpful for damage mechanism analysis and design of garlic production equipment.

关键词： garlic bulb collision restitution coefficient high-speed photography experimental tests

基于熵权和层次分析法的高层建筑火灾风险评价研究——以贵阳某高层建筑为例

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项目管理技术 2024年第4期22卷 12-17页

作者：韩文余照阳刘飞贵州大学矿业学院贵州贵阳550025

当前,我国高层建筑火灾风险评价研究通常采用层次分析法,但该方法受主观性影响较大,评价结果往往不够准确。基于此,采用熵权和层次分析法组合计算各指标综合权重,建立高层建筑火灾风险评价模型,并以贵阳某高层建筑为例进行验证。研究结... 详细信息

当前,我国高层建筑火灾风险评价研究通常采用层次分析法,但该方法受主观性影响较大,评价结果往往不够准确。基于此,采用熵权和层次分析法组合计算各指标综合权重,建立高层建筑火灾风险评价模型,并以贵阳某高层建筑为例进行验证。研究结果显示,该模型具有一定的科学性和合理性。根据研究结果提出相应建议,旨在提升高层建筑火灾风险管理水平。

关键词：熵权法层次分析法高层建筑火灾风险评价

Less pressure contributes to gravity-driven membrane ultrafiltration with greater performance:Enhanced driving efficiency and reduced disinfection by-products formation potential

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Journal of Environmental Sciences 2024年第3期137卷 407-419页

作者： Xiaoting Wu yufei Li zhaoyang Su Long Tian Muhammad Saboor Siddique Wenzheng yu Colleges of Forestry Northeast Forestry UniversityHarbin 150040China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Gravity-driven membrane(GDM)systems have been well developed previously;however,impacts of driving(i.e.,transmembrane)pressure on their performance received little attention,which may infuence GDM performance.In this study,we evaluated 4 GDM systems via altering the transmembrane pressure from 50 mbar to 150 mbar with 2 groups,treating surface water in Beijing,China.Results showed that less driving pressure was more favorable.Specifically,compared to groups(150 mbar),groups under a pressure of 50 mbar were found to have greater normalized permeability and lower total resistance.During the whole operation period,the quality of effuents was gradually improved.For example,the removal efficiency of UV254was significantly improved;particularly,under low driving pressure,the removal efficiency of UV254in PES GDM system increased by 11.91%,as compared to the corresponding system under high driving pressure.This observation was consistent with the reduction on disinfection by-products(DBPs)formation potential;groups under 50 mbar achieved better DBPs potential control,indicating the advantages of lower driving pressure.Biofilms were analyzed and responsible for these differences,and distinct distributions of bacteria communities of two GDM systems under 50 and 150 mbar may be responsible for various humic-like substances removal efficiency.Overall,GDM systems under less pressure should be considered and expected to provide suggestions on the design of GDM systems in real applications.

关键词： Ultrafiltration Gravity driven operation Membrane fouling Biofilms Disinfection by-products

Application of system identification in a practical active noise control system

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Control Theory and Technology 2024年第2期22卷 282-291页

作者： yu yuan zhaoyang Sun Hongwei Zhang School of Mechanical Engineering Xihua UniversityChengdu610039SichuanChina School of Electrical Engineering Southwest Jiaotong UniversityChengdu611756SichuanChina School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen518055GuangdongChina

Noise pollution has become increasingly severe around the world due to fast urbanization. How to soundproof windows from outside noise is of significant interest for both academia and industry. This paper reports an experimental implementation of normalized minmax active noise control (ANC) algorithm on an open window system, where identifying the model of acoustic sound paths plays a central role. By doing this, traffic noise is attenuated by the ANC system, leading to a relatively quiet indoor environment, while the natural lighting and ventilation functions of a window are remained. Our experiments show that an average of 19 dB(A) noise reduction is achieved.

关键词： Active noise control Multi-input-multi-output system Normalized minimax algorithm System identification

Power-efficient programmable integrated multiport photonic interferometer in CMOS-compatible silicon nitride

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Photonics Research 2024年第3期12卷 I0011-I0020页

作者： SHUQING LIN YANFENG ZHANG zhaoyang WU SHIHAO ZENG QING GAO JIAQI LI XIAOQUN yu SIyuAN yu State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China Hefei National Laboratory Hefei 230088China

Silicon nitride(SiNx)is an appealing waveguide material choice for large-scale,high-performance photonic integrated circuits(PICs)due to its low optical loss.However,SiNx PICs require high electric power to realize optical reconfiguration via the weak thermo-optic effect,which limits their scalability in terms of device density and chip power dissipation.We report a 6-mode programmable interferometer PIC operating at the wavelength of 1550 nm on a CMOS-compatible low-temperature inductance coupled plasma chemical vapor deposition(ICP-CVD)silicon nitride platform.By employing suspended thermo-optic phase shifters,the PIC achieves 2×improvement in compactness and 10×enhancement in power efficiency compared to conventional devices.Reconfigurable 6-dimensional linear transformations are demonstrated including cyclic transformations and arbitrary unitary matrices.This work demonstrates the feasibility of fabricating power-efficient large-scale reconfigurable PICs on the low-temperature ICP-CVD silicon nitride platform.

关键词： unitary arbitrary figuration

High-speed flexible near-infrared organic photodiode for optical communication

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National Science Review 2024年第3期11卷 227-238页

作者： yu Zhu Hongbin Chen Ruiman Han Hao Qin zhaoyang Yao Hang Liu Yanfeng Ma Xiangjian Wan Guanghui Li Yongsheng Chen The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryTianjin Key Laboratory of Functional Polymer Materials College of Chemistry and Renewable Energy Conversion and Storage Center(RECAST) Nankai University State Key Laboratory of Elemento-Organic Chemistry Nankai University

Optical communication is a particularly compelling technology for tackling the speed and capacity bottlenecks in data communication in modern society. Currently, the silicon photodetector plays a dominant role in high-speed optical communication across the visible-near-infrared spectrum. However, its intrinsic rigid structure, high working bias and low responsivity essentially limit its application in next-generation flexible optoelectronic devices. Herein, we report a narrow-bandgap non-fullerene acceptor（NFA） with a remarkable π-extension in the direction of both central and end units（CH17） with respect to the Y6 series, which demonstrates a more effective and compact 3D molecular packing, leading to lower trap states and energetic disorders in the photoactive film. Consequently, the optimized solution-processed organic photodetector（OPD） with CH17 exhibits a remarkable response time of 91 ns（λ = 880 nm） due to the high charge mobility and low parasitic capacitance, exceeding the values of most commercial Si photodiodes and all NFA-based OPDs operating in self-powered mode. More significantly, the flexible OPD exhibits negligible performance attenuation（<1%） after bending for 500 cycles, and maintains 96% of its initial performance even after 550 h of indoor exposure. Furthermore, the high-speed OPD demonstrates a high data transmission rate of 80 MHz with a bit error rate of 3.5 × 10-4, meaning it has great potential in next-generation high-speed flexible optical communication systems.

关键词： flexible organic photodetector high-speed NIR organic photodetector optical communication light fidelity narrow-bandgap non-fullerene acceptors

Nitrogen and phosphorus fertilization leads to soil arbuscular mycorrhizal fungal diversity changes and rainfed crop yield increase on the Loess Plateau of China:A 37-year study

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Pedosphere 2024年第2期34卷 328-338页

作者： Yi WANG Wenting ZHANG Chunyue LI Shun CHANG yu MIAO Qianxue LI zhaoyang KOU Tinghui DANG State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China

More than 80%of plants form mutualistic symbiotic relationships with arbuscular mycorrhizal fungi(AMF),and the application of fertilizers,such as nitrogen(N)and phosphorus(P)fertilizers,is a common agricultural management practice to improve crop yield and quality.However,the potential effects of long-term N and P fertilization on the AMF community in the rainfed agricultural system of the Loess Plateau of China are still not well understood.In this study,a long-term field experiment was conducted based on orthogonal design,with three N levels(0,90,and 180 kg ha^(-1)year^(-1))and three P levels(0,90,and 180 kg ha^(-1)year^(-1))for wheat fertilization.Changes in AMF community and correlations between AMF community composition,soil environmental factors,and wheat yield component traits were analyzed using traditional biochemical methods and high-throughput sequencing technology.The results showed that long-term N and P addition had a significant effect on the AMF community structure and composition.Nitrogen application alone significantly reduced the richness and diversity of AMF community,whereas the combined application of N and P significantly increased the richness and diversity of AMF community.The AMF community was driven mainly by soil available P,total P,and pH.There was a significant positive correlation between Glomus abundance and wheat yield and a significant negative correlation between Paraglomus abundance and wheat yield.Long-term N and P addition directly increased crop yield and affected yield indirectly by influencing soil chemical properties and the AMF community.Combined application of N and P both at90 kg ha^(-1)year^(-1)could improve the ecological and physiological functions of the AMF community and benefit the sustainable development of rainfed agriculture.

关键词： Glomus long-term fertilization microbial community Paraglomus rainfed agriculture wheat