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矿物冶金与材料学报:英文版 2023年第10期30卷 1868-1877页

作者： jinshan wang Feng Li Si Zhao Lituo Zheng Yiyin Huang Zhensheng Hong Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials College of Physics and EnergyFujian Normal UniversityFuzhou 350117China Academy of Carbon Neutrality of Fujian Normal University Fuzhou 350117China

To meet the low-cost concept advocated by the sodium metal anode,this paper reports the use of a pulsed electrodeposition technology with ionic liquids as electrolytes to achieve uniform nanoplating of metallic magnesium films at around 20 nm on spaced titanium dioxide(TiO_(2))nanotubes(STNA-Mg).First,the sodiophilic magnesium metal coating can effectively reduce the nucleation overpotential of sodium metal.Moreover,three-dimensional STNA can limit the volume expansion during sodium metal plating and stripping to achieve the ultrastable deposition and stripping of sodium metals with a high Coulombic efficiency of up to 99.5%and a small voltage polarization of 5 mV in symmetric Na||Na batteries.In addition,the comparative study of sodium metal deposition behavior of STNA-Mg and STNA-Cu prepared by the same route further confirmed the advantage of magnesium metal to guide sodium metal growth.Finally,the prepared STNA-Mg-Na metal anode and commercial sodium vanadium phosphate cathode were assembled into a full cell,delivering a discharge capacity of 110.2 mAh·g^(-1)with a retention rate of 95.6%after 110 cycles at 1C rate.

关键词： sodium metal anode titanium dioxide nanotubes skeleton electrodeposition metallic magnesium coating

冷却表面温差对高温质子交换膜燃料电池性能的影响

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化工学报 2024年第5期75卷 2026-2035页

作者：王金山王世学朱禹天津大学机械工程学院天津300350 天津大学国家储能技术产教融合创新平台天津300350

通过建立高温质子交换膜燃料电池数学模型,模拟了冷却表面存在不同温差时燃料电池内热-电-质的传输特性,分析了温差对电池内温度分布、氧浓度分布、极化曲线、膜质子电导率和电流密度的影响。结果表明:膜内温度和质子电导率随着冷却表... 详细信息

通过建立高温质子交换膜燃料电池数学模型,模拟了冷却表面存在不同温差时燃料电池内热-电-质的传输特性,分析了温差对电池内温度分布、氧浓度分布、极化曲线、膜质子电导率和电流密度的影响。结果表明:膜内温度和质子电导率随着冷却表面温度的降低而降低;催化层内的局部氧浓度随着冷却表面温差(即温度梯度)的增大而增大,但电流密度受温度及反应物浓度双重因素影响,电流密度及功率密度随着温度梯度的增大而下降。当冷却表面温度梯度从0增加至0.82 K/cm时,峰值功率密度从0.578 W/cm2下降到0.523 W/cm2,下降了9.52%。控制工作电压大于0.5 V、温度梯度小于0.20 K/cm时可获得较好的电流密度均匀性。当工作电压为0.5 V,冷却表面温度梯度为0.20 K/cm时,电流密度均匀性为92.71%。

关键词：燃料电池传热传质数值模拟电流密度均匀性

High Quality Audio Object Coding Framework Based on Non-Negative Matrix Factorization

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China Communications 2017年第9期14卷 32-41页

作者： Tingzhao Wu Ruimin Hu Xiaochen wang Shanfa Ke jinshan wang National Engineering Research Center for Multimedia Software School of Computer ScienceWuhan University Hubei Key Laboratory of Multimedia and Network Communication Engineering Wuhan University Collaborative Innovation Center of Geospatial Technology

Object-based audio coding is the main technique of audio scene coding. It can effectively reconstruct each object trajectory, besides provide sufficient flexibility for personalized audio scene reconstruction. So more and more attentions have been paid to the object-based audio coding. However, existing object-based techniques have poor sound quality because of low parameter frequency domain resolution. In order to achieve high quality audio object coding, we propose a new coding framework with introducing the non-negative matrix factorization(NMF) method. We extract object parameters with high resolution to improve sound quality, and apply NMF method to parameter coding to reduce the high bitrate caused by high resolution. And the experimental results have shown that the proposed framework can improve the coding quality by 25%, so it can provide a better solution to encode audio scene in a more flexible and higher quality way.

关键词： object-based audio coding non-negative matrix factorization audio scenecoding

Global Dynamics of a Multi-group SEIR Epidemic Model with Infection Age

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Chinese Annals of Mathematics,Series B 2021年第6期42卷 833-860页

作者： Vijay Pal BAJIYA Jai Prakash TRIPATHI Vipul KAKKAR jinshan wang Guiquan SUN Department of Mathematics Central University of RajasthanBandar Sindri-305817KishangarhAjmerRajasthanIndia Complex Systems Research Center Shanxi UniversityTaiyuan 030006China Department of Mathematics North University of ChinaTaiyuan 030051China Complex Systems Research Center Shanxi UniversityTaiyuan 030006China.

Consider the heterogeneity(e.g.,heterogeneous social behaviour,heterogeneity due to different geography,contrasting contact patterns and different numbers of sexual partners etc.)of host population,in this paper,the authors propose an infection age multigroup SEIR epidemic model.The model system also incorporates the feedback variables,where the infectivity of infected individuals may depend on the infection age.In the direction of mathematical analysis of model,the basic reproduction number R_0 has been computed.The global stability of disease-free equilibrium and endemic equilibrium have been established in the term of R_(0).More precisely,for R_(0)≤1,the disease-free equilibrium is globally asymptotically stable and for R_(0)>1,they establish global stability of endemic equilibrium using some graph theoretic techniques to Lyapunov function method.By considering a numerical example,they investigate the effects of infection age and feedback on the prevalence of the disease.Their result shows that feedback parameters have different and even opposite effects on different groups.However,by choosing an appropriate value of feedback parameters,the disease could be eradicated or maintained at endemic level.Besides,the infection age of infected individuals may also change the behaviour of the disease,global stable to damped oscillations or damped oscillations to global stable.

关键词： Multi-group model Infection age Feedback Graph-theoretic approach Lyapunov function

脉冲星风云3C58的非热多波段辐射与动力学演化特性

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高师理科学刊 2024年第4期44卷 73-76页

作者：王金山钟响徐国芹卢方武玉溪师范学院物理系云南玉溪653100

脉冲星风云3C58是由脉冲星PSR J0205+6499驱动的星云,具有明显的非热多波段辐射特征.基于包含星云动力学过程的谱演化模型,拟合了该脉冲星风云的多波段非热辐射谱,探究了其多波段能谱随时间的演化特征.模型结果表明,脉冲星风云3C58的多... 详细信息

脉冲星风云3C58是由脉冲星PSR J0205+6499驱动的星云,具有明显的非热多波段辐射特征.基于包含星云动力学过程的谱演化模型,拟合了该脉冲星风云的多波段非热辐射谱,探究了其多波段能谱随时间的演化特征.模型结果表明,脉冲星风云3C58的多波段辐射流量随时间具有明显的演化特征.

关键词： 3C58 非热多波段辐射动力学演化

天然来源的表面活性剂在超低渗油藏开发中的应用

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当代化工 2024年第6期53卷 1277-1281页

作者：王金山秦瑞廖鑫羽李佳豪王超陶震广东南油服务有限公司海口分公司

因为国内大部分油田目前已经进入开发后期，在孔渗较好的圈闭已经钻探殆尽的大背景下，超低渗油藏开发便成了主要研究方向。在开发实践中，采用皂苷为原料制备了一种新型表面活性剂，这种活性剂为天然来源，并通过界面张力、接触角和石... 详细信息

因为国内大部分油田目前已经进入开发后期，在孔渗较好的圈闭已经钻探殆尽的大背景下，超低渗油藏开发便成了主要研究方向。在开发实践中，采用皂苷为原料制备了一种新型表面活性剂，这种活性剂为天然来源，并通过界面张力、接触角和石油采收率评估等实验说明其在以碳酸盐岩为代表的超低渗储层中具有良好的应用价值。评估了表面活性剂产生泡沫并在微观和宏观尺度上建立稳定乳液的能力。研究结果表明，当表面活性剂质量浓度达到1 800 mg·L-1时，界面张力将大幅度降低，最低达到0.39 mN·m-1。此外，通过优化盐度，界面张力将降低到最低0.36 mN·m-1，这表明了盐度控制对于降低界面张力的作用。实验结果表明，该天然来源的新型表面活性剂在其临界胶束浓度下表现出优异的乳液稳定性，持续了6个月性质未发生显著变化；这种新型的表面活性剂产生的泡沫同样表现出了显著的稳定性，半衰期长达30 min。因此，在最佳条件下进行的驱油实验中，该新型表面活性剂溶液处于其临界胶束浓度并且盐度和碱度水平得到优化，原油采收率显著提高了25%，相比于传统的表面活性剂具有更为良好的化学性质，为未来的超低渗透油藏开发带来显著增益。

关键词：石油开发表面活性剂皂苷超低渗透油藏界面张力

A new type of lipophilic hydrophobic self-repairing cellulose insulating paper developed with ST-110/FAS/PTFE ternary system as coating substrate

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High Voltage 2024年第2期9卷 474-483页

作者： Zhenglin Zeng jinshan Qin Zuhao wang Weimin Tan Chao Tang College of Engineering and Technology Southwest UniversityChongqingChina International R&D Center for New Technologies of Smart Grid and Equipment ChongqingChina

The moisture generated by the ageing of the oil-paper insulating system can easily lead to the deterioration of the performance of the insulating paper.In order to alleviate the impact of moisture on the performance of the insulating paper,we developed a kind of lipophilic hydrophobic self-repairing cellulose insulating paper(new insulating paper)based on the ternary system of polytetrafluoroethylene,fluorocarbon surfactant and fluorinated alkyl silane,and accelerated thermal ageing test for 45 days at 130°C was carried out.The experimental results show that the new insulating paper with excellent lipophilic property can realise hydrophobic self-repairing through heat treatment after physical damage.The tensile strength and elongation at break of the new insulating paper increased by 5%–8%and 6.25%–27%respectively compared with the original cellulose insulating paper.At the end of ageing,the relative dielectric constant and dielectric loss factor of new insulating paper are 10.4%and 9.9%lower than that of the original cel-lulose insulating paper,while the breakdown voltage is 6.8%higher.The acid and moisture content produced during the ageing process of the insulating oil impregnated with new insulating paper are also less,indicating that the coating can delay the ageing of the insulating paper.

关键词： coating moisture cellulose

Discovering the ultralow thermal conductive A_(2)B_(2)O_(7)-type high-entropy oxides through the hybrid knowle dge-assiste d data-driven machine learning

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Journal of Materials Science & Technology 2024年第1期168卷 131-142页

作者： Ying Zhang Ke Ren William Yi wang Xingyu Gao Ruihao Yuan Jun wang Yiguang wang Haifeng Song Xiubing Liang jinshan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Innovation Center NPU ChongqingChongqing 401135China Institute of Advanced Structure Technology Beijing Institute of TechnologyHaidian DistrictBeijing 100081China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Defense Innovation Institute Academy of Military Sciences of the PLA of ChinaBeijing 100071China

Lattice engineering and distortion have been considered one kind of effective strategies for discovering advanced materials.The instinct chemical flexibility of high-entropy oxides(HEOs)motivates/accelerates to tailor the target properties through phase transformations and lattice distortion.Here,a hybrid knowledge-assisted data-driven machine learning(ML)strategy is utilized to discover the A_(2)B_(2)O_(7)-type HEOs with low thermal conductivity(κ)through 17 rare-earth(RE=Sc,Y,La-Lu)solutes optimized A-site.A designing routine integrating the ML and high throughput first principles has been proposed to predict the key physical parameter(KPPs)correlated to the targetedκof advanced HEOs.Among the smart-designed 6188(5RE_(0.2))_(2)Zr_(2)O_(7)HEOs,the best candidates are addressed and validated by the princi-ples of severe lattice distortion and local phase transformation,which effectively reduceκby the strong multi-phonon scattering and weak interatomic interactions.Particularly,(Sc_(0.2)Y_(0.2)La_(0.2)Ce_(0.2)Pr_(0.2))_(2)Zr_(2)O_(7)with predictedκbelow 1.59 Wm^(−1)K^(−1)is selected to be verified,which matches well with the ex-perimentalκ=1.69 Wm^(−1)K^(−1)at 300 K and could be further decreased to 0.14 Wm^(−1)K^(−1)at 1473 K.Moreover,the coupling effects of lattice vibrations and charges on heat transfer are revealed by the cross-validations of various models,indicating that the weak bonds with low electronegativity and few bond-ing charge density and the lattice distortion(r∗)identified by cation radius ratio(r A/r B)should be the KPPs to decreaseκefficiently.This work supports an intelligent designing strategy with limited atomic and electronic KPPs to accelerate the development of advanced multi-component HEOs with proper-ties/performance at multi-scales.

关键词： High-entropy oxides Thermal conductivity Pyrochlore Key physical parameter First-Principles

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饮用水处理工艺中VBNC状态细菌研究现状

净水技术 2024年第4期43卷 68-75页

作者：兰童雍绍文王金山罗晓峰钱江刘成陈卫河海大学浅水湖泊综合治理与资源开发教育部重点实验室江苏南京210098 河海大学环境学院江苏南京210098 宁夏水投银川水务有限公司宁夏银川750201

活的非可培养(viable but non-culturable,VBNC)状态是某些细菌在不良环境中进入的一种特殊休眠状态,在条件适宜时可复苏并恢复其致病性,因此,VBNC状态的水源性致病菌会对饮用水安全和人类健康造成潜在威胁。文中简要综述了饮用水处理... 详细信息

活的非可培养(viable but non-culturable,VBNC)状态是某些细菌在不良环境中进入的一种特殊休眠状态,在条件适宜时可复苏并恢复其致病性,因此,VBNC状态的水源性致病菌会对饮用水安全和人类健康造成潜在威胁。文中简要综述了饮用水处理工艺中VBNC细菌的研究现状,分析了VBNC状态细菌形成和复苏的影响条件和作用机制,探讨了常规饮用水处理工艺对VBNC细菌的影响。论文可为有效控制饮用水中VBNC细菌、保障饮用水安全提供一定的参考。

关键词：活的非可培养状态饮用水安全诱导复苏臭氧-生物活性炭工艺

Numerical Investigations on the Steady and Unsteady Leakage Flow and Heat Transfer Characteristics of Rotor Blade Squealer Tip

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Journal of Thermal Science 2011年第4期20卷 304-311页

作者： Jun LI Hao SUN jinshan wang Zhenping FENG Institute of Turbomachinery Xi＇an Jiaotong University Xi＇an 710049 CHINA

The steady and unsteady leakage flow and heat transfer characteristics of the rotor blade squealer tip were conducted by solving Reynolds-Averaged Navier-Stokes(RANS) equations with k-ω turbulence model.The first stage of GE-E3 engine with squealer tip in the rotor was adopted to perform this work.The tip clearance was set to be 1% of the rotor blade height and the groove depth was specified as 2% of the span.The results showed that there were two vortexes in the tip gap which determined the local heat transfer characteristics.In the steady flow field,the high heat transfer coefficient existed at several positions.In the unsteady case,the flow field in the squealer tip was mainly influenced by the upstream wake and the interaction of the blades potential fields.These unsteady effects induced the periodic variation of the leakage flow and the vortexes,which resulted in the fluctuation of the heat transfer coefficient.The largest fluctuation of the heat transfer coefficient on the surface of the groove bottom exceeded 16% of the averaged value on the surface of the squealer tip.

关键词：传热特性泄漏流量不稳定数值研究旋翼 Stokes 转子叶片传热系数