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Machine learning method to predict dynamic compressive response of concrete-like material at high strain rates

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Defence Technology（防务技术） 2023年第5期23卷 100-111页

作者： Xu Long Ming-hui Mao Tian-xiong su Yu-tai su Meng-ke Tian School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'anChina School of Civil Engineering Liaoning Petrochemical UniversityFushunChina Beijing Microelectronics Technology Institute BeijingChina

Machine learning(ML)methods with good applicability to complex and highly nonlinear sequences have been attracting much attention in recent years for predictions of complicated mechanical properties of various *** one of the widely known ML methods,back-propagation(BP)neural networks with and without optimization by genetic algorithm(GA)are also established for comparisons of time cost and prediction *** the aim to further increase the prediction accuracy and efficiency,this paper proposes a long short-term memory(LSTM)networks model to predict the dynamic compressive performance of concrete-like materials at high strain *** explicit analysis is performed in the finite element(FE)software ABAQUS to simulate various waveforms in the split Hopkinson pressure bar(SHPB)experiments by applying different stress waves in the incident *** FE simulation accuracy is validated against SHPB experimental results from the viewpoint of dynamic increase *** order to cover more extensive loading scenarios,60 sets of FE simulations are conducted in this paper to generate three kinds of waveforms in the incident and transmission bars of SHPB *** training the proposed three networks,the nonlinear mapping relations can be reasonably established between incident,reflect,and transmission *** measures are used to quantify the network prediction accuracy,confirming that the predicted stress-strain curves of concrete-like materials at high strain rates by the proposed networks agree sufficiently with those by FE *** is found that compared with BP network,the GA-BP network can effectively stabilize the network structure,indicating that the GA optimization improves the prediction accuracy of the SHPB dynamic responses by performing the crossover and mutation operations of weights and thresholds in the original BP *** eliminating the long-time dependencies,the proposed LSTM network achieves better results than the BP

关键词： Deep learning LSTM network GA-BP network Dynamic behaviour Concrete-like materials

Internal mammary artery steal syndrome secondary to a para-IMA after coronary artery bypass graft： a case report

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Journal of Geriatric Cardiology 2009年第4期6卷 241-243页

作者： Jie Gao Pi-xiong su Yan Liu Department of Cardiac surgery Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China

Introduction The use of the intemal mammary artery （IMA） in coronary artery bypass graft（CABG） for myocardial revascularization is gaining popularity in routine practice, especially when the target vessel is the left anterior descending artery （LAD）. Occasionally, IMA hypoperfusion occurs when there is inadequate flow through the IMA graft to the LAD artery due to the exist of lateral branches.

关键词：冠状动脉 IMA 搭桥综合征继发窃取乳流量不足

CO_2 methanation over TiO_2–Al_2O_3 binary oxides supported Ru catalysts

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Chinese Journal of Chemical Engineering 2016年第1期24卷 140-145页

作者： Jinghua Xu Qingquan Lin xiong su Hongmin Duan Haoran Geng Yanqiang Huang School of Materials Science and Engineering Shandong University State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Yantai University Shandong Applied Research Center of Gold Nanotechnology (Au-SDARC)

TiO_2 modified Al_2O_3 binary oxide was prepared by a wet-impregnation method and used as the support for ruthenium catalyst. The catalytic performance of Ru/TiO_2–Al_2O_3catalyst in CO_2 methanation reaction was investigated. Compared with Ru/Al_2O_3 catalyst, the Ru/TiO_2–Al_2O_3catalytic system exhibited a much higher activity in CO_2 methanation reaction. The reaction rate over Ru/TiO_2–Al_2O_3 was 0.59 mol CO_2·(g Ru)1·h-1, 3.1 times higher than that on Ru/Al_2O_3[0.19 mol CO_2·(gRu)-1·h-1]. The effect of TiO_2 content and TiO_2–Al_2O_3calcination temperature on catalytic performance was addressed. The corresponding structures of each catalyst were characterized by means of H_2-TPR, XRD, and TEM. Results indicated that the averaged particle size of the Ru on TiO_2–Al_2O_3support is 2.8 nm, smaller than that on Al_2O_3 support of 4.3 nm. Therefore, we conclude that the improved activity over Ru/TiO_2–Al_2O_3catalyst is originated from the smaller particle size of ruthenium resulting from a strong interaction between Ru and the rutile-TiO_2 support, which hindered the aggregation of Ru nanoparticles.

关键词： CO2 methanation supported Ru catalyst TiO2–Al2O3 binary oxide

The influence of intimacy on the ’iterative reactions’ during OX-ZEO process for aromatic production

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Journal of Energy Chemistry 2019年第8期28卷 60-65,I0003页

作者： Xiaoli Yang Ting sun Junguo Ma xiong su Ruifeng Wang Yaru Zhang Hongmin Duan Yanqiang Huang Tao Zhang State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023 Liaoning China University of Chinese Academy of Sciences Beijing 100049China College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068 Sichuan China

The oxide-zeolite process provides a promising way for one-step production of aromatics from syngas,whereas the reasons for the dramatic effect of intimacy between oxide and zeolite in the composite catalyst on the product selectivity are still unclear. In order to explore the optimal intimacy and the essential influence factors, ZnCrOxcombined with ZSM-5 are employed to prepare the composite catalysts with different distances between the two components by changing the mixing methods. An aromatic selectivity of 74%(with CO conversion to be 16%) is achieved by the composite catalyst when the intimacy is in the range of nanometer. A so-called ‘iterative reactions’ mechanism of intermediates over oxides is then proposed and studied: the intermediate chemical can undergo a hydrogenation reaction on *** the shorter the intermediates stay on oxide, the more of chance for C-C coupling takes place on zeolite to form aromatics. Moreover, the aero-environments of reaction is found to impact on the extent of iterative reaction as well. Therefore, when the intimacy between the two components changes, the extent of iterative reactions vary, resulting in alteration of product distribution. This work provides new insight in understanding the mechanisms during the complex process of OX-ZEO composite catalysis and sheds light to the design of a high-yield catalyst for synthetization of aromatics from syngas.

关键词： OX-ZEO process Intimacy Iterative reactions Reaction aero-environment Diffusion

Effect of reduction pretreatment on the structure and catalytic performance of Ir-In_(2)O_(3)catalysts for CO_(2) hydrogenation to methanol

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Journal of Environmental Sciences 2024年第6期140卷 2-11页

作者： Changyu Ding Feifei Yang Xue Ye Chongya Yang Xiaoyan Liu Yuanlong Tan Zheng Shen Hongmin Duan xiong su Yanqiang Huang CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

In_(2)O_(3)has been found a promising application in CO_(2)hydrogenation to methanol,which is beneficial to the utilization of CO_(2).The oxygen vacancy(O_(v))site is identified as the catalytic active center of this ***,there remains a great challenge to understand the relations between the state of oxygen species in In_(2)O_(3)and the catalytic performance for CO_(2)hydrogenation to *** the present work,we compare the properties of multiple In_(2)O_(3)and Ir-promoted In_(2)O_(3)(Ir-In_(2)O_(3))catalysts with different Ir loadings and after being pretreated under different reduction *** CO_(2)conversion rate of Ir-In_(2)O_(3)is more promoted than that of pure In_(2)O_(3).With only a small amount of Ir loading,the highly dispersed Ir species on In_(2)O_(3)increase the concentration of O_(v)sites and enhance the *** finely tuning the catalyst structure,Ir-In_(2)O_(3)with an Ir loading of 0.16 wt.%and pre-reduction treatment under 300℃exhibits the highest methanol yield of 146 mgCH_(3)OH/(gcat·hr).Characterizations of Raman,electron paramagnetic resonance,X-ray photoelectron spectroscopy,CO_(2)-temperature programmed desorption and CO_(2)-pulse adsorption for the catalysts confirm that more O_(v)sites can be generated under higher reduction temperature,which will induce a facile CO_(2)adsorption and desorption *** performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies,which guides us to find more suitable conditions for catalyst pretreatment and reaction.

关键词： Carbon dioxide Hydrogenation Methanol In_(2)O_(3) Fixed-bed Reduction temperature

Membrane regulation of tumorigenesis: a hydroxylation approach

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Membrane regulation of tumorigenesis: a hydroxylation approa...

Designing of highly selective and high-temperature endurable RWGS heterogeneous catalysts: recent advances and the future directions

第四届中国生物物理学会代谢生物学分会学术研讨会

作者： xiong su

＜正＞Alteration in lipid composition is an important metabolic adaptation by cancer cells to support tumorigenesis and metastasis. Hydroxylated fatty acids （OHFAs）occur in various mammalian tissues, which can be provided by food intake and sources of microorganisms or be endogenously generated. Fatty acid2-hydroxylase （FA2H） introduces a chiral hydroxyl group at the second carbon of FA backbones and influences lipid structures and metabolic signaling. Previous studies suggest the presence of unexplored cancer type-dependent mechanisms through which FA 2-hydroxylation is coupled to metabolic adaptation and tumor growth.

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Journal of Energy Chemistry 2017年第5期26卷 854-867页

作者： xiong su Xiaoli Yang Bo Zhao Yanqiang Huang iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Renewable Energy Storage Division Global Energy Interconnection Research Institute (GEIRI)Future Science and Technology City

Reverse water gas shift（RWGS） reaction can be served as a pivotal stage of transitioning the abundant CO;resource into chemicals or hydrocarbon fuels, which is attractive for the CO;utilization and of eventually significance in enabling a rebuilt ecological system for unconventional fuels. This concept is appealing when the process is considered as a solution for the storage of renewable energy, which may also find a variety of potential end uses for the outer space exploration. However, a big challenge to this issue is the rational design of high temperature endurable RWGS catalysts with desirable CO product selectivity. In this work, we present a comprehensive overview of recent publications on this research topic,mainly focusing on the catalytic performance of RWGS reaction over three major kinds of heterogeneous catalysts, including supported metal catalysts, mixed oxide catalysts and transition metal carbides. The reaction thermodynamic analysis, kinetics and mechanisms are also described in detail. The present review attempts to provide a general guideline about the construction of well-performed heterogeneous catalysts for the RWGS reaction, as well as discussing the challenges and further prospects of this process.

关键词： RWGS reaction Carbon dioxide hydrogenation supported metal catalyst Metal oxide Transition metal carbide

THROMBOENDARTERECTOMY FOR CHRONIC PULMONARY THROMBOEMBOLISM

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Chinese Medical Sciences Journal 2005年第3期20卷 194-197页

作者： Hua Ren Pi-xiong su Chao-ji Zhang Song Gu Heng Zhang Chen Wang Department of Cardiovascular surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 Department of Cardiovascular surgery Chaoyang Hospital Beijing 100007 Department of Respiratory Medicine Chaoyang Hospital Beijing 100007

Objective To evaluate the improving reliability and safety of thromboendarterectomy and perioperative management for chronic pulmonary thromboembolism. Methods The clinical data of 12 cases with chronic pulmonary thromboembolism, who underwent thromboendarterec- tomy assisted by low flow or circulation arrest with deep hypothermia, were reviewed retrospectively. Results Pulmonary artery pressure decreased 20 to 40 mmHg immediately after surgical procedures in 9 cases. The postoperative pulmonary edema at various degrees happened in 12 cases, among them, 1 died of severe lung infection and pulmonary re-embolism at 19 days postoperation. Computed tomography pulmonary angiography and angiography of 11 cases indicated that the original obstruction of pulmonary artery disappeared. During the follow-up period of 2 months to 5 years, the clinical symptoms and activity was improved. Conclusion Thromboendarterectomy is an effective treatment for chronic pulmonary thromboembolism. The outcome of the surgical procedure needs to be further investigated and followed up regularly according to an evaluative system, because it might be influenced by multiple factors.

关键词： chronic pulmonary thromboembolism .thromboendarterectomy pulmonary hypertension postoperative pulmonary edema

A Systematic Approach for Making 3D-Printed Patient-Specific Implants for Craniomaxillofacial Reconstruction

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Engineering 2020年第11期6卷 1291-1301页

作者： Ruxu Du Yu-xiong su Yu Yan Wing Shan Choi Wei-Fa Yang Chunyu Zhang Xianshuai Chen Justin Paul Curtin Jianglin Ouyang Bitao Zhang Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou 511442China Oral and Maxillofacial surgery Faculty of DentistryThe University of Hong KongHong Kong 999077China Foshan Angels Biotechnology Co. Ltd.Foshan 528200China

Craniomaxillofacial reconstruction implants,which are extensively used in head and neck surgery,are conventionally made in standardized *** surgery,the implant must be bended manually to match the anatomy of the individual *** bending process is time-consuming,especially for inexperienced ***,repetitive bending may induce undesirable internal stress concentration,resulting in fatigue under masticatory loading in v iv o and causing various complications such as implant fracture,screw loosening,and bone *** have been reports on the use of patient-specific 3D-printed implants for craniomaxillofacial reconstruction,although few reports have considered implant *** this paper,we present a systematic approach for making 3D-printed patientspecific surgical implants for craniomaxillofacial *** approach consists of three parts:First,an easy-to-use design module is developed using Solidworks®software,which helps surgeons to design the implants and the axillary fixtures for *** engineers can then carry out the detailed design and use finite-element modeling(FEM)to optimize the ***,the fabrication process is carried out in three steps:0 testing the quality of the powder;(2)setting up the appropriate process parameters and running the 3D printing process;and (3)conducting post-processing treatments(i.e.,heat and surface treatments)to ensure the quality and performance of the ***,the operation begins after the final checking of the implant and *** the surgery,postoperative rehabilitation follow-up can be carried out using our patient tracking *** this systematic approach,we have successfully conducted a total of 41 surgical cases.3D-printed patient-specific implants have a number of advantages;in particular,their use reduces surgery time and shortens patient recovery ***,the presented approach helps to ensure implant quality.

关键词： Patient-specific implant Craniomaxillofacial reconstruction 3D printing surgery