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Science China Mathematics 2005年第z1期48卷 413-423页

作者： zhang wenjuan Department of Mathematics Capital Normal UniversityBeijing100037China

The Bergman kernel function for Hua Construction of the third type is given in an explicit formula.

关键词： Hua Construction Bergman kernel function bolomorphic automorphism.

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含氧化膜钛合金裂纹尖端氢扩散分析

热加工工艺 2025年第2期54卷 132-138页

作者：杨富强张越张剑洲闫涛张文娟西安科技大学理学院陕西西安710054 西安科技大学机械学院陕西西安710054

基于扩散和应力耦合的质量平衡方程,建立了外界环境氢渗入覆盖TiO2裂尖并扩散的数学模型。通过在COMSOL中采用有限元法构建具有钝化裂纹尖端的平板计算模型,讨论了氧化膜厚度和裂尖应力状态对氢扩散的影响。结果表明,裂尖氢渗入与扩散... 详细信息

基于扩散和应力耦合的质量平衡方程,建立了外界环境氢渗入覆盖TiO2裂尖并扩散的数学模型。通过在COMSOL中采用有限元法构建具有钝化裂纹尖端的平板计算模型,讨论了氧化膜厚度和裂尖应力状态对氢扩散的影响。结果表明,裂尖氢渗入与扩散受到氧化膜的引入和厚度增加的抑制,外载荷增加会抑制环境中的氢向裂尖渗入,并减少了裂尖的氢富集。应力梯度引起的裂尖氢扩散效果在低浓度时更显著。

关键词：钛合金氢扩散氧化膜应力 COMSOL

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赤铁矿分离法回收钕铁硼废料

有色金属(冶炼部分) 2025年第2期 133-139页

作者：吴金玲阳启华王日张文娟中稀(凉山)稀土有限公司四川凉山615000 北京科技大学冶金与生态工程学院北京100083

从钕铁硼废料中高效回收稀土是缓解稀土资源紧张局势的重要途径。目前,从钕铁硼废料中回收稀土的难点在于稀土与铁的深度分离。利用赤铁矿除铁法分离钕铁硼废料中的Fe,达到稀土与Fe深度分离的目的。针对影响稀土浸出率及稀土与铁分离效... 详细信息

从钕铁硼废料中高效回收稀土是缓解稀土资源紧张局势的重要途径。目前,从钕铁硼废料中回收稀土的难点在于稀土与铁的深度分离。利用赤铁矿除铁法分离钕铁硼废料中的Fe,达到稀土与Fe深度分离的目的。针对影响稀土浸出率及稀土与铁分离效果的因素进行了详细的考察。结果表明:在氧化剂NaNO_(3)用量60 mg/g原料,HCl用量0.663 mL/g,浸出温度180℃,浸出时间3 h,液固比2.5 mL/g,搅拌速度300 r/min的条件下,REO和镨钕浸出率分别为95.91%、97.99%,酸浸液铁与稀土的浸出选择性s(Fe2O_(3)/REO)为4.37%。XRD及SEM结果显示酸浸渣主要成分为过滤性能良好的赤铁矿。

关键词：钕铁硼废料赤铁矿法稀土深度分离

Homogeneity-preserving property of harmonic sequences from surfaces into complex Grassmann manifolds

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Frontiers of Mathematics in China 2017年第5期12卷 1131-1137页

作者： Jie FEI wenjuan zhang Department of Mathematical Sciences Xi'an Jiaotong-Liverpool UniversitySuzhou 215123 China School of Science East China University of Technology Nanchang 330013 China

We prove that if φ is a homogeneous harmonic map from a Riemann surface M into a complex Grassmann manifold G（k, n）, then the maps of the harmonic sequences generated by φ are all homogeneous.

关键词： Complex Grassmann manifold harmonic sequence homogeneoussurface

Solar-driven H_(2)O_(2)synthesis from H_(2)O and O_(2)over molecular engineered organic framework photocatalysts

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Chinese Journal of Catalysis 2024年第11期66卷 76-109页

作者： wenjuan zhang Gang Liu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012JilinChina College of Chemistry Jilin UniversityChangchun 130012JilinChina

H_(2)O_(2)is an environmentally friendly oxidant and a promising energy-containing molecule widely applied in industrial production,environmental remediation,and as a potential carrier for energy ***-driven conversion of earth-abundant H_(2)O and O_(2)is the most ideal method for producing H_(2)O_(2).Due to poor separation of photogenerated charge carriers in semiconductors,sacrificial reagents such as ethanol are typically added to consume photogenerated holes,but this is not an energy storage ***,developing efficient photocatalysts for direct H_(2)O_(2)production from H_(2)O and O_(2)without sacrificial agents is crucial for sustainable energy *** framework materials,due to their customizable structures,have gained traction in the photosynthesis of H_(2)O_(2)from pure H_(2)O and O_(2).A series of functionalized molecules have been introduced as building blocks into organic frameworks to enhance the H_(2)O_(2)production performance,but their key roles in performance and reaction pathways have not been summarized in detail so *** review aims to address this gap and elucidate the relationship between the structure and performance of organic framework photocatalysts,providing insights and guidance for the development of efficient photocatalysts.

关键词： Organic framework Photocatalyst H_(2)O_(2)photosynthesis Molecular engineering Solar energy conversion

Ozonation of aromatic monomer compounds in water: factors determining reaction outcomes

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Frontiers of Environmental Science & Engineering 2023年第5期17卷 13-25页

作者： Zhe Wang wenjuan zhang Zhiwei Wang Jing Chang School of Environmental Science and Safety Engineering Tianjin University of TechnologyTianjin 300384China School of Environmental and Municipal Engineering Tianjin Key Laboratory of Aquatic Science and TechnologyTianjin Chengjian UniversityTianjin 300384China Tianjin Municipal Engineering Design&Research Institute Co. Ltd.Tianjin 300384China

For aromatic monomer compounds (AMCs), ozonation outcomes were usually predicted by the substituents of the benzene ring based on the electron inductive effect. However, the predicted results were occasionally unreliable for complex substituents, and other factors caused concern. In this study, p-chloronitrobenzene (p-CNB) and ibuprofen (IBP) were selected for ozonation. According to the electron inductive theory, p-CNB should be less oxidizable, but the opposite was true. The higher rates of p-CNB were due to various sources of assistance. First, the hydroxyl radical (•OH) contributed 90 % to p-CNB removal at pH 7.0, while its contribution to IBP removal was 50 %. Other contributions came from molecular O3 oxidation. Second, p-CNB achieved 40 % of the total organic carbon (TOC) removal and fewer by-product types and quantities, when compared to the results for IBP. Third, the oxidation of p-CNB started with hydroxyl substitution reactions on the benzene ring;then, the ring opened. However, IBP was initially oxidized mainly on the butane branched chain, with a chain-shortening process occurring before the ring opened. Finally, the degradation pathway of p-CNB was single and consumed fewer oxidants. However, both branches of IBP were attacked simultaneously, and three degradation pathways that relied on more oxidants were proposed. All of these factors were determinants of the rapid removal of p-CNB.

关键词： Ozonation Aromatic compound Oxidizing specie By-product Initial reaction position Degradation pathway

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Comprehensive utilization of complex rubidium ore resources:Mineral dissociation and selective leaching of rubidium and potassium

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International Journal of Minerals,Metallurgy and Materials 2023年第5期30卷 857-867页

作者： Quankuang zhang Baozhong Ma Chengyan Wang Yongqiang Chen wenjuan zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Currently,the process of extracting rubidium from ores has attracted a great deal of attention due to the increasing application of rubidium in high-technology field.A novel process for the comprehensive utilization of rubidium ore resources is proposed in this *** process consists mainly of mineral dissociation,selective leaching,and *** results showed that the stable silicon–oxygen tetrahedral structure of the rubidium ore was completely disrupted by thermal activation and the mineral was completely dissociated,which was conducive to subsequent selective *** the optimal conditions,extractions of 98.67% Rb and 96.23%K were obtained by leaching the rubidium ***,the addition of a certain amount of activated Al(OH)_(3) during leaching can effectively inhibit the leaching of *** the meantime,the leach residue was sodalite,which was successfully synthesized to zeolite A by hydrothermal *** proposed process provided a feasible strategy for the green extraction of rubidium and the sustainable utilization of various resources.

关键词： rubidium mineral dissociation selective leaching zeolite A desilication

Using maximum likelihood method to detect adaptive evolution of HCV envelope protein-coding genes

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Chinese Science Bulletin 2006年第18期51卷 2236-2242页

作者： zhang wenjuan zhang Yuan ZHONG Yang School of Life Sciences Fudan University Shanghai 200433 China Shanghai Center for Bioinformation Technology Shanghai 201203 China

Nonsynonymous-synonymous substitu- tion rate ratio (dN/dS) is an important measure for evaluating selective pressure based on the pro- tein-coding sequences. Maximum likelihood (ML) method with codon-substitution models is a powerful statistic tool for detecting amino acid sites under positive selection and adaptive evolution. We ana- lyzed the hepatitis C virus (HCV) envelope pro- tein-coding sequences from 18 general geno/ sub- types worldwide,and found 4 amino acid sites under positive selection. Since these sites are located in different immune epitopes,it is reasonable to antici- pate that our study would have potential values in biomedicine. It also suggests that the ML method is an effective way to detect adaptive evolution in virus proteins with relatively high genetic diversity.

关键词：适应进化阳性选择氨基酸肝炎病毒包膜蛋白 HCV

Application of Lightning Data Assimilation to Numerical Forecast of Super Typhoon Haiyan (2013)

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Journal of Meteorological Research 2020年第5期34卷 1052-1067页

作者： Rong zhang wenjuan zhang Yijun zhang Jianing FENG Liangtao XU State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological Administration(CMA)Beijing 100081 Key Laboratory for Cloud Physics of CMA Chinese Academy of Meteorological SciencesCMABeijing 100081 Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200438

Previous observations from World Wide Lightning Location Network(WWLLN) and satellites have shown that typhoon-related lightning data have a potential to improve the forecast of typhoon intensity. The current study was aimed at investigating whether assimilating TC lightning data in numerical models can play such a role. For the case of Super Typhoon Haiyan in 2013, the lightning data assimilation(LDA) was realized in the Weather Research and Forecasting(WRF) model, and the impact of LDA on numerical prediction of Haiyan’s intensity was *** data from WWLLN were used to adjust the model’s relative humidity(RH) based on the method developed by Dixon et al.(2016). The adjusted RH was output as a pseudo sounding observation, which was then assimilated into the WRF system by using the three-dimensional variational(3DVAR) method in the cycling mode at 1-h intervals. Sensitivity experiments showed that, for Super Typhoon Haiyan(2013), which was characterized by a high proportion of the inner-core(within 100 km from the typhoon center) lightning, assimilation of the inner-core lightning data significantly improved its intensity forecast, while assimilation of the lightning data in the rainbands(100–500 km from the typhoon center) led to no obvious improvement. The improvement became more evident with the increase in LDA cycles, and at least three or four LDA cycles were needed to achieve obvious intensity forecast improvement. Overall, the improvement in the intensity forecast by assimilation of the inner-core lightning data could be maintained for about 48 h. However, it should be noted that the LDA method in this study may have a negative effect when the simulated typhoon is stronger than the observed, since the LDA method cannot suppress the spurious convection.

关键词： lightning three-dimensional variational(3DVAR)data assimilation Typhoon Haiyan typhoon intensity

工程项目集成数字交付模式下的价值共创机制:基于服务生态系统视角

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管理评论 2025年第1期37卷 257-272页

作者：王广斌杨宇琛张文娟刘刚曹冬平同济大学经济与管理学院上海200092 同济大学机械与能源工程学院上海200092 广联达科技股份有限公司数字建筑研究院北京100193 清华大学土木水利学院北京100084

在高质量发展战略驱动下,价值驱动成为工程管理的发展方向。集成数字交付(integrated digital delivery,IDD)是实现工程项目价值交付的一种创新执行框架。本文聚焦IDD模式的价值共创过程,基于服务生态系统视角,选取SPS(structured-pragm... 详细信息

在高质量发展战略驱动下,价值驱动成为工程管理的发展方向。集成数字交付(integrated digital delivery,IDD)是实现工程项目价值交付的一种创新执行框架。本文聚焦IDD模式的价值共创过程,基于服务生态系统视角,选取SPS(structured-pragmatic-situational)案例研究方法对一个典型项目展开单案例研究,构建了IDD模式实现价值共创的机制模型。研究发现:(1)IDD是基于服务生态系统的价值共创模式,项目参与方构成了A2A导向的松散耦合网络;(2)各类制度从强制性、指导性和自主性三个维度治理参与方间关系,引导各方基于项目价值做出决策和行动;(3)数字技术支持各参与方开展跨阶段协作,促成项目工作流程的集成和简化;(4)行为交互是价值共创的先决条件,为各参与方创造了介入其他参与方价值创造过程的机会;(5)异质性资源整合所创造的涌现价值,是IDD模式下价值产生的根源。本文创新性地将工程项目抽象为服务生态系统,揭示了IDD模式如何在各种要素的组合作用下实现价值共创,为工程项目价值共创研究和服务主导逻辑体系做出理论贡献。

关键词：集成数字交付价值共创服务生态系统服务主导逻辑