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Research progress of slippage characteristic and gas film stability enhancement methods on biomimetic hydrophobic surfaces

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Journal of Hydrodynamics 2024年第1期36卷 87-101页

作者： Meng-zhuo Zhang Hai-bao hu Liu-zhen Ren Lu-yao Bao Jun Wen Luo Xie School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China

The biomimetic hydrophobic surface is a potentially efficient underwater drag reduction method and the drag reduction mechanism of this kind of surface comes from the interfacial *** now,it is a hotspot to grasp the slippage characteristic and explore slippage enhancement *** paper not only summarizes our numerical simulation and experimental results of slippage characteristic at the solid-liquid interface(SLI)of hydrophobic surfaces(HS)and the gas-liquid interface(GLI)of superhydrophobic surfaces(SHS)in recent years,but also introduces some innovative methods that can effectively improve the gas film stability and drag reduction effect of ***,we used the molecular dynamics(MD)simulation method to figure out the effect of the solid-liquid interaction strength,the system temperature and the shear rate on the slippage of SLI,and expound their action mechanism from molecular ***,by MD and multibody dissipative particle dynamics(MDPD)method,the slippage behavior at the GLI was studied under the influence of the microstructure size and the flow driving *** proposed a new kind of hybrid slip boundary condition model to describe the slippage characteristic on *** addition,we found through experiment that a three-dimensional backflow will appear on the GLI under the interfacial adsorption of surfactants,and the backflow direction will reverse with the change of GLI ***,we put forward the wettability step structure and gas injection method to enhance the stability and drag reduction effect of the gas film on SHS.

关键词： Hydrophobic surface superhydrophobic surface interfacial slip underwater drag reduction

Effect of Nozzle Inclination Angle on Fuel-Air Mixing and Combustion in a Heavy Fuel Engine

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Fluid Dynamics & Materials Processing 2024年第2期20卷 365-382页

作者： Zhigang Wang bin Zheng Peidong Zhao Baoli Wang Fanyan Meng Wenke Xu Jian Meng School of Transportation and Vehicle Engineering Shandong University of TechnologyZibo255049China

Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power *** this study,a combustion model for an in-cylinder direct injection engine has been imple-mented using the AVL FIRE *** effects of the angle of nozzle inclination on fuel evaporation,mixture distribution,and combustion in the engine cylinder have been systematically studied at 5500 r/min and consider-ing full load cruise *** to the results,as the angle of nozzle inclination increases,the maximum combustion explosion pressure in the cylinderﬁrst increases and then it *** the angle of nozzle incli-nation is less than 45°,the quality of the mixture in the cylinder and the combustion performance can be improved by increasing the *** the angle of nozzle inclination is greater than 45°,however,the mixture unevenness increases slightly with the angle,leading to a deterioration of the combustion *** the angle of nozzle inclination is between 35°and 55°,the overall combustion performance of the engine is rela-tively *** the angle of nozzle inclination is 45°,the combustion chamber’s geometry and the cylinder’s airﬂow are well matched with the fuel spray,and the mixture quality is the *** with 25°,the peak heat release rate increases by 20%,and the maximum combustion burst pressure increases by 5.5%.

关键词： Aviation heavy fuel piston engine nozzle inclination angle combustion fuel-air mixing

韧性领导对员工适应性绩效的影响:有调节的链式中介模型

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商业经济与管理 2024年第8期 51-62页

作者：何斌简浩胡卫敏广东工业大学管理学院广东广州510520

领导风格是影响员工适应性绩效的重要前因,然而尚未有研究探索韧性领导这一VUCA时代新型领导风格与员工适应性绩效的关系。基于资源保存理论和扩展—建构理论,探索韧性领导对员工适应性绩效的预测作用及其作用机制和边界条件,拓展韧性... 详细信息

领导风格是影响员工适应性绩效的重要前因,然而尚未有研究探索韧性领导这一VUCA时代新型领导风格与员工适应性绩效的关系。基于资源保存理论和扩展—建构理论,探索韧性领导对员工适应性绩效的预测作用及其作用机制和边界条件,拓展韧性领导的影响结果和员工适应性绩效的预测前因。利用层级回归分析技术,分析来源于两阶段收集的225份网络调查问卷,结果发现:韧性领导显著正向影响员工适应性绩效;工作繁荣和自我领导分别中介了韧性领导与员工适应性绩效的关系;工作繁荣与自我领导在韧性领导与员工适应性绩效之间发挥链式中介作用;环境不确定性调节了韧性领导与工作繁荣的关系以及韧性领导经由工作繁荣和自我领导对员工适应性绩效的链式中介效应。研究结果有助于丰富韧性领导和员工适应性绩效的相关研究,为组织提升员工适应性绩效提供有益借鉴。

关键词：韧性领导员工适应性绩效工作繁荣自我领导环境不确定性

A novel lead-free relaxor with endotaxial nanostructures for capacitive energy storage

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SusMat 2024年第1期4卷 116-125页

作者： Xiaoyan Dong Tengfei hu XiaojunWu Jie Yin Zhengqian Fu Jiagang Wu College of Materials Science and Engineering Sichuan UniversityChengduP.R.China Analysis and Testing Center for Inorganic Materials Shanghai Institute of CeramicsChinese Academy of SciencesShanghaiP.R.China

Dielectric capacitors with a fast charging/discharging rate,high power density,and long-term stability are essential components in modern electrical ***,miniaturizing and integrating capacitors face a persistent challenge in improving their energy density(W_(rec))to satisfy the specifications of advanced electronic systems and *** this work,leveraging phase-field simulations,we judiciously designed a novel lead-free relaxor ferroelectric material for enhanced energy storage performance,featuring flexible distributed weakly polar endotaxial nanostructures(ENs)embedded within a strongly polar fluctuation *** matrix contributes to substantially enhanced polarization under an external electric field,and the randomly dispersed ENs effectively optimize breakdown phase proportion and provide a strong restoring force,which are advantageous in bolstering breakdown strength and minimizing ***,this relaxor ferroelectric system incorporating ENs achieves an exceptionally high W_(rec)value of 10.3 J/cm^(3),accompanied by a large energy storage efficiency(η)of 85.4%.This work introduces a promising avenue for designing new relaxor materials capable of capacitive energy storage with exceptional performance characteristics.

关键词： endotaxial nanostructure energy storage lead-free relaxor ferroelectric

Effect of cobalt substitution for nickel on microstructural evolution and hydrogen storage properties of La_(0.66)Mg_(0.34)Ni_(3.5-x)Co_(x) alloys

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Journal of Rare Earths 2024年第5期42卷 930-939,I0004页

作者： Xincong He huazhou hu Ruizhu Tang Wenhao Zhou Houqun Xiao Xiaoxuan Zhang Chuanming Ma Qingjun Chen School of Rare Earths University Science&Technology of ChinaHefei230026China Key Laboratory of Rare Earths Chinese Academy of SciencesJiangxi Institute of Rare EarthsGanjiang Innovation AcademyChinese Academy of SciencesGanzhou341000China

Superlattice hydrogen storage alloys offer a compelling advantage with rapid hydriding rate and high storage ***,its practical applications face challenges including complex structure,low dehydriding capacity,and cyclic *** this work,we successfully prepared La_(0.66)Mg_(0.34)Ni_(3.5-x)Co_(x) superlattice hydrogen storage alloys with enhanced dehydriding capacity and stability by partially substituting Co for Ni.X-ray diffraction(XRD)refinements analysis reveals the presence of(La,Mg)_(3)Ni_(9),(La,Mg)_5Ni_(19),and LaNi_(5) phases within the *** Co substitution in the La_(0.06)Mg_(0.34)Ni_(3.4)Co_(0.1)alloy,there is a significant increase in content of the(La,Mg)_(3)Ni_(9) phase and a reduction in the hysteresis factor,resulting in an improved reversible hydrogen storage capacity from 1.45 wt%to 1.60 wt%.The dehydriding kinetics of the alloy is controlled by diffusion model with an activation energy of 8.40 kJ/***,the dehydriding enthalpy value of the Co-substituted alloy decreases from 30.84 to 29.85 kJ/***,the cycling performance of the alloy after Co substitution exhibits excellent stability,with a capacity retention rate of 92.3%after 100 *** findings provide valuable insights for the development of cost-effective hydrogen storage materials.

关键词： Superlattice hydrogen storage alloy Co substitution Microstructure Kinetics Thermodynamics Rare earths

Synthesis and optical properties of highly efficient Na_(3)KMg_(7)(PO_(4))_(6):Eu^(2+)blue phosphor for full-spectrum white-light-emitting diodes:The role of Li_(2)CO_(3)flux

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Journal of Rare Earths 2024年第7期42卷 1217-1223,I0001页

作者： Zihao Wang Sisi Liang Chenyang Zhan Kunyuan Xu Jie hu Dejian Chen Liping Song Haomiao Zhu School of Physics and Materials Science Nanchang UniversityNanchang330000China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Research Center of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen361021China

Full-spectrum phosphor-converted white-light-emitting diodes(pc-WLED)are emerging as a mainstream technology in semiconductor ***,high-performance blue phosphor which can be excited efficiently by a 400 nm NUV diode chip is still ***,we present a blue-emitting Na_(3)KMg_(7)(PO_(4))6:Eu^(2+)phosphor synthesized by the solid-reaction ***,we find that the using of Li_(2)CO_(3)as flux can significantly improve the crystal quality and thus the emission efficiency of the ***,the excitation peak of the phosphor shifts from 365 to 400 nm,which is pivotal for efficient NUV(400 nm)diode chip *** practical Eu^(2+)concentration is also enhanced by using Li_(2)CO_(3)as flux,and the absorption efficiency is greatly *** phosphor exhibits superior PL thermal stability,namely retains 94%integrated photoluminescence intensity at 150℃of that at 25℃.As a result,the optimized phosphor shows an emission band peaked at 437 nm with a bandwidth of 40 nm and a high external photoluminescence quantum yield of 51.7%.Finally,a pc-WLED was fabricated by using NKMPO:Eu^(2+)blue,Sr_(2)SiO_(4):Eu^(2+)green,CaAlSiN_(3):Eu^(2+)red phosphors,and a 400 nm NUV diode *** shows a high color rendering index of R_(a)=96.4 and a correlated color temperature of 4358 *** results prove that NKMPO:Eu^(2+)is a promising blue phosphor for full-spectrum WLED based on NUV diode chips.

关键词： Eu^(2+) Blue phosphor Na_(3)KMg_(7)(PO_(4))_(6) Full-spectrum white LEDs Rare earths

Comparative analysis of thermodynamic and mechanical responses between underground hydrogen storage and compressed air energy storage in lined rock caverns

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International Journal of Mining Science and Technology 2024年第4期34卷 531-543页

作者： Bowen hu Liyuan Yu Xianzhen Mi Fei Xu Shuchen Li Wei Li Chao Wei Tao Zhang State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Large Structure Health Monitoring and Control Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

Underground hydrogen storage(UHS)and compressed air energy storage(CAES)are two viable largescale energy storage technologies for mitigating the intermittency of wind and solar ***,it is meaningful to compare the properties of hydrogen and air with typical thermodynamic storage *** study employs a multi-physical coupling model to compare the operations of CAES and UHS,integrating gas thermodynamics within caverns,thermal conduction,and mechanical deformation around rock *** thermodynamic responses are validated using additional simulations and the field test *** and pressure variations of air and hydrogen within rock caverns exhibit similarities under both adiabatic and diabatic simulation *** reaches higher temperature and pressure following gas charging stage compared to air,and the ideal gas assumption may lead to overestimation of gas temperature and *** steel lining of CAES,the sealing layer(fibre-reinforced plastic FRP)in UHS is prone to deformation but can effectively mitigates stress in the sealing *** CAES,the first principal stress on the surface of the sealing layer and concrete lining is tensile stress,whereas UHS exhibits compressive stress in the same *** present research can provide references for the selection of energy storage methods.

关键词： Underground hydrogen storage Compressed air energy storage Mechanical response Thermodynamic response Lined rock caverns

shRNA—CXCR4对人胃癌BGC823细胞增殖迁移的影响

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中华实验外科杂志 2011年第11期28卷 1899-1902页

作者：朱志强宁忠良胡斌汤志刚安徽医科大学附属省立医院普外科合肥230001

目的构建针对人CXCR4基因的shRNA干扰表达载体，观察CXCR4基因表达对人胃癌细胞株BGC823细胞增殖和迁移能力的影响。方法根据人CXCR4序列设计并构建CXCR4基因的shRNA真核表达载体，以脂质体转染的方法将CXCR4干扰质粒转染至人胃癌细胞株... 详细信息

目的构建针对人CXCR4基因的shRNA干扰表达载体，观察CXCR4基因表达对人胃癌细胞株BGC823细胞增殖和迁移能力的影响。方法根据人CXCR4序列设计并构建CXCR4基因的shRNA真核表达载体，以脂质体转染的方法将CXCR4干扰质粒转染至人胃癌细胞株BGC823，经G418筛选出稳定转染的阳性细胞，应用流式细胞仪技术检测其细胞周期变化，噻唑蓝（MTT）比色法检测CXCR4干扰对胃癌细胞增殖的影响，采用Trans—well小室法检测细胞体外迁移能力。结果经测序证明CXCR4的shRNA基因已成功插入Psilencer4．1质粒中，构建的干扰质粒能够显著抑制CXCR4的表达，CXCR4mRNA被抑制了（2．7±0．2）倍（P〈0．01）。CXCR4基因的表达下调将胃癌细胞阻滞在G1期（由84．2％升至94．1％），MTT法检测CXCR4-shRNA干扰细胞增殖（P〈0．05），且穿过Trans—well小室膜的细胞数显著下降（P〈0．05）。结论干扰CXCR4的表达可显著抑制胃癌细胞的增殖和迁移能力。

关键词：胃癌增殖 shRNA CXCR4

Utilizing interpretable stacking ensemble learning and NSGA-Ⅲ for the prediction and optimisation of building photo-thermal environment and energy consumption

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Building Simulation 2024年第5期17卷 819-838页

作者： Yeqin Shen Yubing hu Kai Cheng Hainan Yan Kaixiang Cai Jianye hua Xuemin Fei Qinyu Wang School of Arts Jiangsu UniversityZhenjiang212013China School of Architecture and Urban Planning Nanjing UniversityNanjing210093China School of Computer Science and Communication Engineering Jiangsu UniversityZhenjiang212013China

This study develops an approach consisting of a stacking model integrated with a multi-objective optimisation algorithm aimed at predicting and optimising the ecological performance of *** integrated model consists of five base models and a meta-model,which significantly improves the prediction ***,the R2 value was improved by 9.19% and the error metrics MAE,MSE,MAPE,and CVRMSE were reduced by 69.47%,79.88%,67.32%,and 57.02%,respectively,compared to the single prediction *** to the research on interpretable machine learning,adding the SHAP value gives us a deeper understanding of the impact of each architectural design parameter on the *** the multi-objective optimisation part,we used the NSGA-Ⅲ algorithm to successfully improve the energy efficiency,daylight utilisation and thermal comfort of the ***,the optimal design solution reduces the energy use intensity by 31.6 kWh/m^(2),improves the useful daylight index by 39%,and modulated the thermal comfort index,resulting in a decrement of 0.69℃ for the summer season and an enhancement of 0.64℃ for the winter season,***,this study provides building designers and decision makers with a tool to make better design decisions at an early stage to achieve a better combination of energy efficiency,daylight utilisation and thermal comfort optimisation in an integrated manner,providing an important support for achieving sustainable building design.

关键词： building ecological performance ensemble learning multi-objective optimisation sustainable design explainable machine learning