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Research on feed-pulse collaborative control method in micro-electrical discharge machining

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Advances in Manufacturing 2024年第2期12卷 270-287页

作者： Qiang Gao Ya-Ou Zhang Xue-Cheng Xi yuan-ding wang Xiao-Fei Chen Wan-Sheng Zhao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240People’s Republic of China State Key Laboratory of Mechanical System and Vibration Shanghai200240People’s Republic of China Shanghai Institute of Space Propulsion Shanghai201112People’s Republic of China

Reducing the short-circuit rate and increasing the effective discharge rate are important targets for improving the servo control effect of micro-electrical discharge machining(micro-EDM),as these two indicators are closely related to the machining efficiency and *** this study,a feed-pulse collaborative control(FPCC)method is proposed for micro-EDM based on two dimensions(space and time).In the spatial dimension,a feed control strategy with a discharge holding process is ***,in the time dimension,a forward-looking pulse control strategy is adopted,in which the pulse interval is adjusted based on a sequence analysis of feed commands and discharge *** experiments are carried out to determine the key parameters used in this method,including the discharge holding threshold and pulse interval adjustment value(T_(off_(adj))).The feed smoothness and discharge sufficiency analyses of the experimental results show that compared to the traditional double threshold average voltage method,the FPCC method reduces the number of long-distance retreats by 64%and improves the effective discharge time by 40%.

关键词： Micro-electrical discharge machining(micro-EDM) Electrode feed control Discharge pulse control Machining surface quality

Delaying Modified QUICK Scheme and its Application in Slug Flow

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Journal of Thermal Science 2001年第2期10卷 139-143页

作者： LU yuan-Wei HE An-ding wang Yue-She ZHOU Fang-De The National Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an China

The National Laboratory of Multiphase Flow in Power Engineering Xi' an Jiaotong University, Xi' an 710049, China Abstract:Calculations of several classic questions in numerical heat transfer with delaying modified QUICK scheme show good agreement with benchrnark. Combining volume of fluid model with the well known SIMPLEC method. the reasonanble Tgylor bubble shape has ben obtained by using delaying modified QUICK scheme and donor acceptor scheme of interfacial advection respectively. At the same the the stream field and the liquid film thickness around the Taylor bubble have been well figured out

关键词： slug flow Taylor-bubbles QUICK scheme SIMPLEC method.

不同领域科学家影响力评价文献回顾及实证分析

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情报杂志 2016年第10期35卷 100-105页

作者：丁媛王红大连理工大学图书馆大连116024

[目的/意义]如何建立一套科学、客观的评价体系,用于科研管理部门对科研人员的遴选,成为科研管理的一项必要且基础的工作。[方法/过程]通过比较目前国外对不同领域科学家评价的方法,构建了科研人才发表论文被引和引用参考文献评价指数,... 详细信息

[目的/意义]如何建立一套科学、客观的评价体系,用于科研管理部门对科研人员的遴选,成为科研管理的一项必要且基础的工作。[方法/过程]通过比较目前国外对不同领域科学家评价的方法,构建了科研人才发表论文被引和引用参考文献评价指数,并进行了实证分析。[结果/结论]SNCS指数将作者所在的学科进行标准化运算,修正不同学科期刊引用行为的影响,考虑了作者在发文文献中的排名,更为客观的评价了不同学科学者科研绩效。

关键词：科学家评价 H指数 Cf指数被引标准化指数施引标准化指数 SNCS

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying ding Ying-Chao Li yuan-Feng Wu yuan-Yang Xu Rui Chen Xiao-Lei Zhao Hai-Yong wang Da-Lei Zhang Yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng Cai Shengjun Miao yuan Li Yu wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Reconstruction characteristics of gut microbiota from patients with type 1 diabetes affect the phenotypic reproducibility of glucose metabolism in mice

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Science China Life Sciences 2025年第1期68卷 176-188页

作者： Zhiyi wang Mengxue Gong yuanyuan Fang Huijuan yuan Chenhong Zhang State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong University Department of Endocrinology Henan Provincial People's HospitalPeople's Hospital of Zhengzhou University

The human microbiota-associated(HMA) mice model, especially the germ-free(GF)-humanized mice, has been widely used to probe the causal relationships between gut microbiota and human diseases such as type 1 diabetes(T1D). However, most studies have not clarified the extent to which the reconstruction of the human donor microbiota in recipient mice correlates with corresponding phenotypic reproducibility. In this study, we transplanted fecal microbiota from five patients with T1D and four healthy people into GF mice, and microbiota from each donor were transplanted into 10 mice. Mice with similar microbiota structure to the donor exhibited better phenotypic reproducibility. The characteristics of the microbial community assembly of donors also influenced the phenotypic reproducibility in mice, and individuals with a higher proportion of stochastic processes showed more severe disorders. Microbes enriched in patients with T1D had a stronger colonization potential in mice with impaired glucose metabolism, and microbiota functional features related to T1D were better reproduced in these mice. This indicates that assembly traits and colonization efficacy of microbiota influence phenotypic reproducibility in GF-humanized mice. Our findings provide important insights for using HMA mice models to explore links between gut microbiota and human diseases.

关键词： gut microbiome human microbiota-associated animal model type 1 diabetes

Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke:current evidence and future perspectives

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Neural Regeneration Research 2025年第1期20卷 67-81页

作者： Yubo wang Tingli yuan Tianjie Lyu Ling Zhang Meng wang Zhiying He Yongjun wang Zixiao Li Vascular Neurology Department of NeurologyBeijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Shanghai Engineering Research Center of Stem Cells Translational Medicine ShanghaiChina National Center for Healthcare Quality Management in Neurological Diseases Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Institute for Regenerative Medicine Shanghai East HospitalSchool of Life Sciences and TechnologyTongji UniversityShanghaiChina Chinese Institute for Brain Research BeijingChina Research Unit of Artificial Intelligence in Cerebrovascular Disease Chinese Academy of Medical SciencesBeijingChina Beijing Engineering Research Center of Digital Healthcare for Neurological Diseases BeijingChina

Ischemic stroke is a leading cause of death and disability worldwide,with an increasing trend and tendency for onset at a younger ***,in particular,bears a high burden of stroke *** recent years,the inflammatory response after stroke has become a research hotspot:understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its *** review summarizes several major cells involved in the inflammatory response following ischemic stroke,including microglia,neutrophils,monocytes,lymphocytes,and ***,we have also highlighted the recent progress in various treatments for ischemic stroke,particularly in the field of stem cell ***,understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient *** cell therapy may potentially become an important component of ischemic stroke treatment.

关键词： cell therapy immune cell inflammatory ischemic stroke stem cell

Al2O3在Al(111)面形核机理的第一性原理

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火炸药学报 2020年第5期43卷 505-509,I0003页

作者：陈鹏杨超袁定旺郭坤琨湖南大学材料科学与工程学院湖南长沙410082

为了揭示金属Al粉末表面生成无定形Al2O3的反应机理,基于具有周期性边界条件的超晶胞模型,采用第一性原理密度泛函理论中的广义梯度近似计算方法,计算并分析了三氧化二铝(Al2O3)在Al(111)面的形核过程,根据前人的实验结果总结和提出了4... 详细信息

为了揭示金属Al粉末表面生成无定形Al2O3的反应机理,基于具有周期性边界条件的超晶胞模型,采用第一性原理密度泛函理论中的广义梯度近似计算方法,计算并分析了三氧化二铝(Al2O3)在Al(111)面的形核过程,根据前人的实验结果总结和提出了4条反应路径,对O2和Al2O3分子在Al(111)表面的吸附性质进行了结构和能量分析,分别由3个或4个基元步构成。结果表明,首先O2在Al(111)表面吸附时,O2发生O—O键断裂形成中间产物AlO,该中间产物再继续和Al原子、O原子、AlO进一步反应形成Al2O、AlO2、Al2O2等中间产物,最终形成Al2O3。从这些中间产物之间的自由能变化可以看出,AlO和O2参与反应的中间步能量分别下降8.37和8.08 eV,而形成AlO2和Al2O等中间产物时能量分别上升1.27和0.76 eV,但是整个Al2O3形核反应是放热的,即自由能降低15.19 eV。因此,三基元和四基元反应都易在Al表面生成Al2O3。

关键词：量子化学第一性原理 Al粉 Al2O3 形核机理反应路径

Assessing the corrosion protection property of coatings loaded with corrosion inhibitors using the real-time atmospheric corrosion monitoring technique

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 119-126页

作者： Xiaoxue wang Lulu Jin Jinke wang Rongqiao wang Xiuchun Liu Kai Gao Jingli Sun Yong yuan Lingwei Ma Hongchang Qian Dawei Zhang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Institute of Space Long March Vehicle Beijing 100076China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal ***,limited studies have applied ACM to the corrosion protection properties of organic *** study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over *** with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in *** the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy *** trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface *** alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic *** with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.

关键词： atmospheric corrosion monitoring technology corrosion inhibitor coating carbon steel corrosion protection