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氮化铝单晶的布里渊散射几何研究

光散射学报 2013年第2期25卷 138-141页

作者：王赛吴永全周国治李钊孟文健上海大学材料科学与工程学院上海市现代冶金及材料制备重点实验室上海200072 北京科技大学冶金与生态工程学院北京100083

在对称散射和180°背散射两种散射几何设置下获得了单晶透明氮化铝布里渊散射谱图。分析了谱峰出现的原因及其对应的声波模式,分析了对称散射几何设置下谱图的偏振态。实验观察到对称散射谱图中准纵波峰和背散射谱图中的纯纵模峰,分析... 详细信息

在对称散射和180°背散射两种散射几何设置下获得了单晶透明氮化铝布里渊散射谱图。分析了谱峰出现的原因及其对应的声波模式,分析了对称散射几何设置下谱图的偏振态。实验观察到对称散射谱图中准纵波峰和背散射谱图中的纯纵模峰,分析了它们出现的原因。文章根据实验谱图求得了样品材料的全部弹性常数信息。

关键词：布里渊散射对称散射 180°背散射

Catalytic behavior of Mo-Bi-Fe-Co-K-M-O(M=Ce,Gd,CeGd)catalysts for selective oxidation of isobutene

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Journal of Rare Earths 2024年第1期42卷 84-93,I0003页

作者： Qinghui Li Huahua Zhao Jian Yang Jun Zhao Liang Yan Huanling Song Lingjun chou State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

The further improvement of methacrolein(MAL)selectivity from isobutene(IB)oxidation is crucial and *** this study,based on the typical Mo-Bi-Fe-Co-K-O mixed metal oxide,the rare earth element Gd-doped,Ce-doped and CeGd co-doped catalysts were prepared by co-precipitation strategy to increase the selectivity of MAL from 47.9%to 49.8%,64.2% and 68.6%,*** order to elucidate in-depth the promoting effect of Ce and/or Gd,various characterizations were utilized including X-ray diffraction patterns(XRD),Raman,X-ray fluorescence spectrometry(XRF),X-ray photoelectron spectroscopy(XPS),O_(2)-temperature programmed desorption(O_(2)-TPD),H2-temperature programmed reduction(H2-TPR),CO_(2)-temperature programmed desorption(CO_(2)-TPD),IB-temperature programmed desorption(i-C4-TPD)and in-situ IB-Fourier transform infrared spectroscopy(IB-FTIR).Both Ce and Gd finely regulate the bulk and surface structure of the catalyst,thus altering the redox ability,oxygen mobility and storage ability and *** with Ce,Gd addition slightly regulates the variation of Co^(2+)/Co^(3+)redox couples,greatly enhances the interaction among the components on the catalyst,thus only increases the content of surface oxygen species and has little effect on their *** Cecontaining catalyst performs stronger oxygen storage and migration ability,thus leading to the overproduction of surface Odefectspecies,which are proposed to be the active sites for the production of MAL and *** CeGd co-doped catalyst possesses the proper content of surface Odefectspecies,thus exhibits much higher MAL ***,the promoting mechanism of Ce and/or Gd over IB oxidation is ***,this work is helpful for understanding the influence of rare earth elements on the structure of mixed metal oxides and the olefin selective oxidation reaction.

关键词： Mixed metal oxide catalyst Rare earth element Isobutene Selective oxidation Methacrolein

Acquiring Weak Annotations for Tumor Localization in Temporal and Volumetric Data

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Machine Intelligence Research 2024年第2期21卷 318-330页

作者： Yu-Cheng chou Bowen Li Deng-Ping Fan Alan Yuille Zongwei Zhou Department of Computer Science Johns Hopkins UniversityBaltimore 21218USA Computer Vision Lab ETH ZurichZurich 8001Switzerland

Creating large-scale and well-annotated datasets to train AI algorithms is crucial for automated tumor detection and ***,with limited resources,it is challenging to determine the best type of annotations when annotating massive amounts of unlabeled *** address this issue,we focus on polyps in colonoscopy videos and pancreatic tumors in abdominal CT scans;Both applications require significant effort and time for pixel-wise annotation due to the high dimensional nature of the data,involving either temporary or spatial *** this paper,we develop a new annotation strategy,termed Drag&Drop,which simplifies the annotation process to drag and *** annotation strategy is more efficient,particularly for temporal and volumetric imaging,than other types of weak annotations,such as per-pixel,bounding boxes,scribbles,ellipses and ***,to exploit our Drag&Drop annotations,we develop a novel weakly supervised learning method based on the watershed *** results show that our method achieves better detection and localization performance than alternative weak annotations and,more importantly,achieves similar performance to that trained on detailed per-pixel ***,we find that,with limited resources,allocating weak annotations from a diverse patient population can foster models more robust to unseen images than allocating per-pixel annotations for a small set of *** summary,this research proposes an efficient annotation strategy for tumor detection and localization that is less accurate than per-pixel annotations but useful for creating large-scale datasets for screening tumors in various medical modalities.

关键词： Weak annotation detection localization segmentation colonoscopy abdomen

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超细钼铜复合粉体及细晶钼铜合金的制备

粉末冶金技术 2021年第1期39卷 24-32,61页

作者：王敬飞卜春阳何凯吉鑫鹏张和张国华周国治北京科技大学钢铁冶金新技术国家重点实验室北京100083 金堆城钼业股份有限公司西安710077

采用“缺碳预还原+氢气深脱氧”方法制备了不同Cu含量(5%、20%、40%,质量分数)的超细Mo-Cu复合粉末。通过高温煅烧钼酸铵和硝酸铜混合物制备了MoO3和CuO复合氧化物,再利用炭黑预还原脱除煅烧产物(CuMoO4-MoO3)中绝大部分氧的方法制备了... 详细信息

采用“缺碳预还原+氢气深脱氧”方法制备了不同Cu含量(5%、20%、40%,质量分数)的超细Mo-Cu复合粉末。通过高温煅烧钼酸铵和硝酸铜混合物制备了MoO3和CuO复合氧化物,再利用炭黑预还原脱除煅烧产物(CuMoO4-MoO3)中绝大部分氧的方法制备了含有少量MoO2的超细预还原Mo-Cu复合粉体;少量MoO2的存在可以极大降低预还原产物中碳的残留;最后,经氢还原脱除残留的氧制备得到超细、高纯度Mo-Cu复合粉体,粉体粒度约为200 nm。以Mo-Cu复合粉体为原料,经过压坯和烧结制备得到细晶Mo-Cu合金。结果表明,经过1200℃烧结后,随着Cu质量分数由5%增加到20%,合金相对密度由96.3%增加到98.5%,且Mo、Cu两相分布均匀。Mo-Cu合金硬度随Cu含量的增加而先增加后降低,这是由合金相对密度和铜含量对硬度的影响不同所导致的。随着Cu质量分数由5%增加到40%,Mo-Cu合金的热导率由48.5 W·m^−1·K^−1增加到187.2 W·m^−1·K^−1,电导率由18.79%IACS增加到49.48%IACS。

关键词：钼铜合金超细粉末相对密度硬度热导率电导率

An artificial systems,computational experiments and parallel execution-based surface electromyogram-driven anti-disturbance zeroing neurodynamic strategy for upper limb human-robot interaction control

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 511-525页

作者： Yongbai Liu Keping Liu Gang Wang Jiliang Zhang Yao chou Zhongbo Sun Department of Mechanical Engineering Changchun University of TechnologyChangchunChina Department of Control Engineering Changchun University of TechnologyChangchunChina School of Electrical and Information Engineering Jilin Engineering Normal UniversityChangchunChina College of Information Science and Engineering Northeastern UniversityShenyangChina Department of Electrical and Computer Engineering Brigham Young UniversityProvoUtahUSA

In recent years,intelligent robots are extensively applied in the field of the industry and intelligent rehabilitation,wherein the human-robot interaction(HRI)control strategy is a momentous part that needs to be ***,the efficacy and robustness of the HRI control algorithm in the presence of unknown external disturbances deserve to be *** deal with these urgent issues,in this study,artificial systems,computational experiments and a parallel execution intelligent control framework are constructed for the HRI *** upper limb-robotic exoskeleton system is re-modelled as an artificial *** on surface electromyogram-based subject's active motion intention in the practical system,a non-convex function activated anti-disturbance zeroing neurodynamic(NC-ADZND)controller is devised in the artificial system for parallel interaction and HRI control with the practical ***,the linear activation function-based zeroing neurodynamic(LAF-ZND)controller and proportionalderivative(posterior deltoid(PD))controller are presented and *** results substantiate the global convergence and robustness of the proposed controller in the presence of different external *** addition,the simulation results verify that the NC-ADZND controller is better than the LAF-ZND and the PD controllers in respect of convergence order and anti-disturbance characteristics.

关键词： neural network pattern recognition robotics signal processing

Comprehensive analysis and mitigation strategies for safety issues of sodium-ion batteries

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Rare Metals 2024年第4期43卷 1343-1349页

作者： Tao Wei Xiao-Ling Xian Shi-Xue Dou Wei Chen Shu-Lei chou Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou325035China Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon NeutralizationWenzhou325035China Zhejiang Key Laboratory of Carbon Materials College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou325035China Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation CampusWollongongNSW2522Australia

Sodium-ion batteries show great potential as an alternative energy storage system,but safety concerns remain a major hurdle to their mass *** paper analyzes the key factors and mechanisms leading to safety issues,including thermal runaway,sodium dendrite,internal short circuits,and gas *** promising solutions are proposed,such as high-safety electrode materials in the cathode and anode,high-safety electrolytes,and external battery management *** in also we emphasize the importance of selecting appropriate analysis methods and developing reliable failure models while suggesting advanced machine learning tools for *** a comprehensive approach,this study offers valuable recommendations to optimize materials and solutions for improving the safety of sodium-ion batteries.

关键词： Sodium-ion batteries Safety issues Thermal runaway Sodium dendrites

Predictive factors for percutaneous nephrolithotomy bleeding risks

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Asian Journal of Urology 2024年第1期11卷 105-109页

作者： U Phun Loo Chun Hou Yong Guan chou Teh Urology Department Sarawak General HospitalKuchingMalaysia

Objective:This study aimed to identify predictive factors for percutaneous nephrolithotomy(PCNL)bleeding *** better risk stratification,bleeding in high-risk patient can be anticipated and facilitates early ***:A prospective observational study of PCNL performed at our institution was *** adults with radio-opaque renal stones planned for PCNL were included except those with coagulopathy,planned for additional *** including gender,co-morbidities,body mass index,stone burden,puncture site,tract dilatation size,operative position,surgeon's seniority,and operative duration were studied using stepwise multivariate regression analysis to identify the predictive factors associated with higher estimated hemoglobin(Hb)***:Overall,4.86%patients(n=7)received packed cells *** mean estimated Hb deficiency was 1.3(range 0-6.5)g/dL and the median was 1.0 g/*** multivariate regression analysis revealed that absence of hypertension(p=0.024),puncture site(p=0.027),and operative duration(p=0.023)were significantly associated with higher estimated Hb ***,the effect sizes are rather small with partial eta-squared of 0.037,0.066,and 0.038,*** power obtained was 0.621,0.722,and 0.625,*** factors studied did not correlate with Hb ***:Hypertension,puncture site,and operative duration have significant impact on estimated Hb deficiency during ***,the effect size is rather small despite adequate study power ***,operative position(supine or prone),puncture number,or tract dilatation size did not correlate with Hb *** mainstay of reducing bleeding in PCNL is still meticulous operative *** study findings also suggest that PCNL can be safely done by urology trainees under supervision in suitably selected patient,without increasing risk of bleeding.

关键词： Percutaneous nephrolithotomy Predictive factor Risk factor Bleeding Blood loss

Regulating the intrinsic electronic structure of carbon nanofibers with high-spin state Ni for sodium storage with high-power density

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Journal of Materials Science & Technology 2024年第4期171卷 16-23页

作者： Zhijia Zhang Gang Xie Yuefang Chen Yanhao Wei Mengmeng Zhang Shulei chou Yunxiao Wang Yifang Zhang Yong Jiang School of Materials Science and Engineering Institute of Quantum Materials and DevicesState Key Laboratory of Separation Membrane and Membrane ProcessesTiangong UniversityTianjin 300387China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China Institute for Superconducting and Electronic Materials University of WollongongWollongongNSW 2522Australia

Carbon nanofibers(CNFs)with high specific surface area show great potential for sodium storage as a hard carbon ***,CNFs anchored with Ni nanoparticles(CNFs/Ni)were prepared through chemical vapor deposition and impregnation reduction methods,in situ growing on the three-dimensional porous copper current collector(3DP-Cu).The coupling effect of high-spin state Ni nanopar-ticles leads to the increase of defect density and the expansion of lattice spacing of ***,the 3DP-Cu ensures a high loading capacity of CNFs and short ion/electron transport *** an integral binder-free anode,the 3DP-Cu/CNFs/Ni exhibits excellent electrochemical performance,which demon-strates a high specific capacity with 298.5 mAh g^(-1)at 1000 mA g^(-1)after 1500 cycles,and a high power density with 200 mAh g^(-1)over 1000 cycles at 5000 mA g^(-1).Density functional theory calculation re-sults show that the high-spin state Ni regulates the electronic structure of CNFs,which significantly reduces the adsorption energy for Na^(+)(-2.7 Ev)and thus enables high-rate *** regulation of the electronic structure of carbon materials by high-spin state metal provides a new strategy for developing high-power carbonaceous anode materials for sodium-ion batteries.

关键词： Carbon nanofibers Ni nanoparticles High-spin state Sodium-ion batteries Anode materials Density functional theory calculation

AP4 induces JNK1 and a miR-22-3p/FOSL1 feed-forward loop to activate AP-1 and promote colorectal cancer metastasis

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Cancer Communications 2024年第3期44卷 433-437页

作者： Jinjiang chou Markus Kaller Matjaz Rokavec Fangteng Liu Heiko Hermeking Experimental and Molecular Pathology Institute of PathologyMedical FacultyLudwig-Maximilians-Universität MünchenMunichGermany German Cancer Consortium(DKTK) Partner siteMunichGermany German Cancer Research Center(DKFZ) HeidelbergGermany

Dear Editor,Colorectal cancer(CRC)is the third most deadly can-cer worldwide[1].The mortality of CRC has remained high due to limited treatment options for metastatic CRC(mCRC)[2].Epithelial-mesenchymal transition(EMT)is an important contributor to mCRC[2].The c-MYC proto-oncogene(MYC)-induced transcription factor AP4(TFAP4/AP4)isadriverofEMT,therebypresumablyfacil-itates mCRC[3,4].The mitogen-activated protein kinase(MAPK)/c-JunN-terminalkinase(JNK)/activatorprotein-1(AP-1)pathway has been implicated in the regulation of EMT and mCRC[5].

关键词： JNK1 metastasis EMT