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Fe-Mn interdiffusion in aluminosilicate garnets

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Geoscience Frontiers 2024年第1期15卷 118-125页

作者： Yanjun Yin baohua zhang Xinzhuan Guo Key Laboratory of High-temperature and High-pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550081GuizhouChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Big Data in Geosciences and Deep Earth Resources of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou 310058China

Precise determination of cation diffusivity in garnet can provide critical information for quantitatively understanding the timescales and thermodynamics of various geological processes,but very few studies have been performed for Fe-Mn interdiffusion.In this study,Fe-Mn interdiffusion rates in natural single crystals of Mn-bearing garnet with 750 ppm H2O are determined at 6 GPa and 1273-1573 K in a Kawai-type multi-anvil apparatus.Diffusion profiles were acquired by electron microprobe and fitted using Boltzmann-Matano equation.The experimental results show that the Fe-Mn interdiffusion coefficient(DFe-Mn)slightly decreases with increasing XFe.The experimentally determined DFe-Mn in Mn-bearing garnet can be fitted by the Arrhenius equation:DFe-Mn(m2/s)=D0XFenexp(-E*/RT),where E*=(1-XFe)E*Mn+XFeE*Fe,D0=8.06-6.04+9.87×10-9 m2/s,E*Mn=248±27 KJ/mol,E*Fe=226±59 KJ/mol,n=-1.36±0.51.The comparing the present results with previous experimental data suggest that water can greatly enhance the DFe-Mn in garnet.Our results indicate that the time required for homogenization of the compositional zoning of a garnet is much shorter than previously thought.

关键词： Fe-Mn interdiffusion Diffusion coefficient Garnet High pressure experiment Water

Remote estimates of suspended particulate matter in global lakes using machine learning models

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International Soil and Water Conservation Research 2024年第1期12卷 200-216页

作者： Zhidan Wen Qiang Wang Yue Ma Pierre Andre Jacinthe Ge Liu Sijia Li Yingxin Shang Hui Tao Chong Fang Lili Lyu baohua zhang Kaishan Song Northeast Institute of Geography and Agroecology CASChangchunJilin130102China Department of Geology Indiana University∼Purdue UniversityIndianapolisIN44602USA University of Chinese Academy of Sciences Beijing100100China College of Geography and Urban Planning Liaocheng UniversityLiaochengChina

Suspended particulate matter(SPM)in lakes exerts strong impact on light propagation,aquatic ecosystem productivity,which co-varies with nutrients,heavy metal and micro-pollutant in waters.In lakes,SPM exerts strong absorption and backscattering,ultimately affects water leaving signals that can be detected by satellite sensors.Simple regression models based on specific band or hand ratios have been widely used for SPM estimate in the past with moderate accuracy.There are still rooms for model accuracy improvements,and machine learning models may solve the non-linear relationships between spectral variable and SPM in waters.We assembled more than 16,400 in situ measured SPM in lakes from six continents(excluding the Antarctica continent),of which 9640 samples were matched with Landsat overpasses within±7 days.Seven machine learning algorithms and two simple regression methods(linear and partial least squares models)were used to estimate SPM in lakes and the performance were compared.To overcome the problem of imbalance datasets in regression,a Synthetic Minority Over-Sampling technique for regression with Gaussian Noise(SMOGN)was adopted in this study.Through comparison,we found that gradient boosting decision tree(GBDT),random forest(RF),and extreme gradient boosting(XGBoost)models demonstrated good spatiotemporal transferability with SMOGN processed dataset,and has potential to map SPM at different year with good quality of Landsat land surface reflectance images.In all the tested modeling approaches,the GBDT model has accurate calibration(n=6428,R^(2)=0.95,MAPE=29.8%)from SPM collected in 2235 lakes across the world,and the validation(n=3214,R^(2)=0.84,MAPE=38.8%)also exhibited stable performance.Further,the good performances were also exhibited by RF model with calibration(R^(2)=0.93)and validation(R^(2)=0.86,MAPE=24.2%)datasets.We applied GBDT and RF models to map SPM of typical lakes,and satisfactory result was obtained.In addition,the GBDT model was evaluated by historical SPM measurements coincident with di

关键词： Landsat imagery Remote estimation SPM Transferability

Water lubrication of graphene oxide-based materials

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Friction 2022年第7期10卷 977-1004页

作者： Shaoqing XUE Hanglin LI Yumei GUO baohua zhang Jiusheng LI Xiangqiong ZENG Laboratory for Advanced Lubricating Materials Shanghai Advanced Research InstituteChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 201210China School of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China Key Laboratory for Advanced Materials School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Water is as an economic,eco-friendly,and efficient lubricant that has gained widespread attention for manufacturing.Using graphene oxide(GO)-based materials can improve the lubricant efficacy of water lubrication due to their outstanding mechanical properties,water dispersibility,and broad application scenarios.In this review,we offer a brief introduction about the background of water lubrication and GO.Subsequently,the synthesis,structure,and lubrication theory of GO are analyzed.Particular attention is focused on the relationship between pH,concentration,and lubrication efficacy when discussing the tribology behaviors of pristine GO.By compounding or reacting GO with various modifiers,amounts of GO-composites are synthesized and applied as lubricant additives or into frictional pairs for different usage scenarios.These various strategies of GO-composite generate interesting effects on the tribology behaviors.Several application cases of GO-based materials are described in water lubrication,including metal processing and bio-lubrication.The advantages and drawbacks of GO-composites are then discussed.The development of GO-based materials for water lubrication is described including some challenges.

关键词： tribology water lubrication graphene oxide(GO)

Rational design of Cu-based electrocatalysts for electrochemical reduction of carbon dioxide

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Journal of Energy Chemistry 2017年第6期26卷 1050-1066页

作者： baohua zhang Jintao zhang Key Laboratory for Colloid and Interface Chemistry of State Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100ShandongChina

The recent development of Cu-based electrocatalysts for electrochemical reduction of carbon dioxide（CO） has attracted much attention due to their unique activity and selectivity compared to other metal catalysts. Particularly, Cu is the unique electrocatalyst for COelectrochemical reduction with high selectivity to generate a variety of hydrocarbons. In this review, we mainly summarize the recent advances on the rational design of Cu nanostructures, the composition regulation of Cu-based alloys, and the exploitation of advanced supports for improving the catalytic activity and selectivity toward electrochemical reduction of CO. The special focus is to demonstrate how to enhance the activity and selectivity of Cubased electrocatalyst for COreduction. The perspectives and challenges for the development of Cu-based electrocatalysts are also addressed. We hope this review can provide timely and valuable insights into the design of advanced electrocatalytic materials for COelectrochemical reduction.

关键词： Electrocatalysts Copper Alloy Selectivity CO_2 electrochemical reduction Electrocatalytic activity Faradaic efficiency

Epitaxial interface stabilizing iridium dioxide toward the oxygen evolution reaction under high working potentials

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Nano Research 2023年第4期16卷 4767-4774页

作者： Guoqiang Zhao Zhouxin Luo baohua zhang Yaping Chen Xiangzhi Cui Jian Chen Yongfeng Liu Mingxia Gao Hongge Pan Wenping Sun School of Materials Science and Engineering Zhejiang UniversityHangzhou 310058China State Key Lab of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an 710021China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China

Proton exchange membrane water electrolyzer(PEMWE)driven by renewable electricity is a promising technique toward green hydrogen production,but the corrosive environment and high working potential pose severe challenges for developing advanced electrocatalysts for the oxygen evolution reaction(OER).Although Ir-based materials possess relatively balanced activity and stability for the OER,their dissolution behavior cannot be neglected,in particular under high working potentials.In this work,iridium dioxide(IrO_(2))nanoparticles(NPs)were anchored on the surface of exfoliated h-boron nitride(BN)nanosheets(NSs)toward the OER reaction in acid media.Highly active Ir(V)species were stabilized by the epitaxial interface between IrO_(2)and h-BN,and therefore the IrO_(2)/BN delivered stable performance at increased working potentials,while the activity of bare IrO_(2)NPs without h-BN support decreased rapidly.Also,the smaller lattice spacing of h-BN induced compressive strain for IrO_(2),resulting in improved activity.Our results demonstrate the feasibility of stabilizing highly active Ir(V)species for the OER in acid media by constructing robust interface and provide new possibilities toward designing advanced heterostructured electrocatalysts.

关键词： iridium oxide oxygen evolution reaction epitaxial interface electrochemical stability

Diffusion in garnet： a review

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Acta Geochimica 2018年第1期37卷 19-31页

作者： Bowen Li Jianhua Ge baohua zhang Key Laboratory for High-Temperature and High-Pressure Study of the Earth's Interior Institute of GeochemistryChinese Academy of Sciences Guiyang 550081 China University of Chinese Academy of Sciences Beijing 100049China

With improvements on high-pressure experimental techniques in multi-anvil apparatus and the development of new analytical tools, major progress has been made on diffusion in garnets in the past several decades. The data obtained in the experimental determination of diffusion coefficients in garnets are of fundamental importance for diffusion modeling and timescales of geological and planetary processes. In this review, we have compiled experimental data on self-diffusion(Si, O, cations), trace element diffusion(Li, Y, Ga, Cr, Sr, REEs), and interdiffusion(Ca–Fe/Mg, Si–Al) in garnet in the light of new advances and recent applications. In addition, some empirical relationships among diffusion parameters(pre-exponential factor D_0,activation energy E, ionic radius) are also discussed. We hope that this review can provide a useful data digest and guide to future study of diffusion in garnet.

关键词： High temperature and high pressure Diffusion Garnet Point defects

An RNA-RNA crosstalk network involving HMGB1 and RICTOR facilitates hepatocellular carcinoma tumorigenesis by promoting glutamine metabolism and impedes immunotherapy by PD-L1+ exosomes activity

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Signal Transduction and Targeted Therapy 2022年第1期7卷 282-294页

作者： Yanping Wei Xuewu Tang Yibin Ren Yun Yang Fengliang Song Jingbo Fu Shuowu Liu Miao Yu Jing Chen Suyang Wang Kecheng zhang Yexiong Tan Zhipeng Han Lixjn Wei baohua zhang zhangjun Cheng Liang Li Hongyang Wang International Co-operation Laboratory on Signal Transduction Eastern Hepato-Biliary Surgery InstituteSecond Military Medical UniversityShanghaiChina National Center for Liver Cancer ShanghaiChina Hepato-Pancreato-biliary center Zhongda HospitalSchool of MedicineSoutheast UniversityNanjingChina The Third Department of Hepatic Surgery Eastern Hepatobiliary Surgery HospitalShanghaiChina School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Department of Biliary Tract Surgery Eastern Hepatobiliary Surgery HospitalSecond Military Medical UniversityShanghaiChina Tumor Immunology and Gene Therapy Center Eastern Hepato-Biliary Surgery InstituteSecond Military Medical UniversityShanghaiChina National Laboratory for Oncogenes and Related Genes Cancer InstituteRenJi HospitalShanghai Jiao Tong University200441 ShanghaiChina

Hepatocellular carcinoma(HCC)is the global leading cause of cancer-related deaths due to the deficiency of targets for precision therapy.A new modality of epigenetic regulation has emerged involving RNA-RNA crosstalk networks where two or more competing endogenous RNAs(ceRNAs)bind to the same microRNAs.However,the contribution of such mechanisms in HCC has not been well studied.Herein,potential HMGB1-driven RNA-RNA crosstalk networks were evaluated at different HCC stages,identifying the mT0RC2 component RICTOR as a potential HMGB1 ceRNA in HBV^(+)early stage HCC.Indeed,elevated HMGB1 mRNA was found to promote the expressio n of RICTOR mRNA through competitively bin ding with the miR-200 family,especially miR-429.Functio nal assays emplo ying overexpressi on or in terference strategies dem on strated that the HMGB1 and RICTOR 3zuntra nslated regions(UTR)epigenetically promoted the malignant proliferation,self-renewal,and tumorigenesis in HCC cells.Intriguingly,in terference agai nst HMGB1 and RICTOR in HCC cells promoted a stron ger an ti-PD-L1 immuno therapy resp on se,which appeared to associate with the production of PD-L1^(+)exosomes.Mechanistically,the HMGB1-driven RNA-RNA crosstalk network facilitated HCC cell glutamine metabolism via dual mechanisms,activating a positive feedback loop involving mT0RC2-AKT-C-MYC to upregulate glutamine synthetase(GS)expression,and inducing mTORCI signaling to derepress SIRT4 on glutamate dehydrogenase(GDH).Meanwhile,this crosstalk network could impede the efficacy of immunotherapy through mTORCI-P70S6K dependent PD-L1 production and PD-L1^(+)exosomes activity.In conclusion,our study highlights the non-coding regulatory role of HMGB1 with implicatio ns for RNA-based therapeutic targeting together with a predictio n of an ti-PD-L1 immuno therapy in HCC.

关键词： metabolism network crosstalk

Well-dispersed SnO2 nanocrystals on N-doped carbon nanowires as efficient electrocatalysts for carbon dioxide reduction

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Journal of Energy Chemistry 2020年第2期29卷 7-14页

作者： baohua zhang Lizhen Sun Yueqing Wang Si Chen Jintao zhang Shenzhen Research Institute of Shandong University Virtural University ParkNanshanShenzhen 518057GuangdongChina Key Laboratory for Colloid and Interface Chemistry of State Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100ShandongChina Shandong Institute of Food and Drug Control Jinan 250101ShandongChina

The conversion of carbon dioxide into valuable organic compounds is a highly promising approach to address the energy issues and environmental problems(e.g., global warming). Herein, we presents a facile and efficient method to prepare highly dense and well-dispersed SnO2 nanocrystals on 1 D N-doped carbon nanowires as advanced catalysts for the efficient electroreduction of CO2 to formate. The ultrasmall SnO2 coated on the N-doped carbon nanowires(SnO2@N-CNW) has been synthesized via the simple hydrothermal treatment coupled with a pyrolysis process. The unique structure enables to expose the active tin oxide and also provides the facile pathways for rapid transfer of electron and electrolyte along with the highly porous carbon foam composed with interconnected carbon nanowires. Therefore, SnO2@NCNW electrocatalyst exhibits good durability and high selectivity for formate formation with a Faradaic efficiency of ca. 90%. This work demonstrates a simple method to rationally design high-dense tin oxide nanocrystals on the conductive carbon support as advanced catalysts for CO2 electroreduction.

关键词： SnO2 nanocrystal N-doping Electrocatalyst Carbon dioxide reduction Carbon nanowire

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基于分工和模糊控制的粒子群算法

复杂系统与复杂性科学 2024年第1期21卷 109-118页

作者：李金张纪会高学柳张保华青岛大学复杂性科学研究所山东青岛266071 青岛大学山东省工业控制技术重点实验室山东青岛266071 青岛港国际股份有限公司山东青岛266011

为解决粒子群算法在求解复杂优化问题时容易陷入局部最优、寻优精度低、后期收敛慢等问题,提出一种基于分工和模糊控制的粒子群算法,使用分工、参数自适应调整和融合距离因素的模拟退火三种策略对粒子群算法进行改进。将粒子分为侦察粒... 详细信息

为解决粒子群算法在求解复杂优化问题时容易陷入局部最优、寻优精度低、后期收敛慢等问题,提出一种基于分工和模糊控制的粒子群算法,使用分工、参数自适应调整和融合距离因素的模拟退火三种策略对粒子群算法进行改进。将粒子分为侦察粒子和后卫粒子,侦察粒子负责进行探索,后卫粒子向个体最优解和全局最优解学习,保证种群多样性并加快搜索速度;使用Sigmoid函数调节惯性权重,模糊逻辑控制学习因子,以平衡算法的探索和开发能力;以模拟退火机制更新全局最优粒子,同时兼顾距离因素,增强算法跳出局部最优解的能力。采用25个标准测试函数进行仿真实验,仿真结果表明,改进算法在收敛精度、速度和稳定性上都有更好表现。

关键词：群体智能粒子群算法个体最优更新率分工策略模糊逻辑模拟退火