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The Al_(2)O_(3)and Mn/Al_(2)O_(3)sorbents highly utilized in destructive sorption of NF_(3)

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Chinese Journal of Chemical Engineering 2024年第1期65卷 54-62页

作者： Yanfei pan Hejian Li Li Zheng Xiufeng Xu School of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China

NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse ***,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse *** the technologies for NF_(3)abatement,the destructive sorption of NF_(3)over metal oxides sorbents is an effective ***,the search for a highly reactive and utilized sorbent for NF_(3)destruction is in great *** this work,AlOOH supported on carbon-sphere(AlOOH/CS)as precursors were synthesized hydrothermally and heat-treated to prepare the Al_(2)O_(3)*** influence of AlOOH/CS hydrothermal temperatures on the reactivity of derived Al_(2)O_(3)sorbents for NF_(3)destruction was investigated,and it is shown that the Al2O3 from AlOOH/CS hydro-thermalized at 120℃is superior to ***,the optimized Al_(2)O_(3)was covered by Mn(OH)x to prepare Mn/Al_(2)O_(3)sorbents via changing hydrothermal temperatures and Mn *** results show that the Mn/Al_(2)O_(3)sorbents are more utilized than bare Al_(2)O_(3)in NF_(3)destructive sorption due to the promotional effect of Mn_(2)O_(3)as surface layer on the fluorination of Al_(2)O_(3)as substrate,especially the optimal 5%Mn/Al2O3(160℃)exhibits a utilization percentage as high as 90.4%,and remarkably exceeds all the sorbents reported so *** findings are beneficial to develop more efficient sorbents for the destruction of NF_(3).

关键词： Greenhouse gas NF_(3)destructive sorption Sorbents Al_(2)O_(3) Mn/Al_(2)O_(3) Reactivity

Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： Wei Li Xin pan Dehong Ge Jinji Gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty *** accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite *** can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment *** composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed *** fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery *** experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation

Real-Time Intelligent Diagnosis of Co-frequency Vibration Faults in Rotating Machinery Based on Lightweight-Convolutional Neural Networks

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 264-282页

作者： Xin pan Xiancheng Zhang Zhinong Jiang Guangfu Bin Beijing Key Laboratory of Health Monitoring and Self-recovery for High-End Mechanical Equipment College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Engine Health Monitoring-Control and Networking(Ministry of Education) College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Mechanical Engineering Hunan University of Science and TechnologyXiangtan 411201China

The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the health state and carrying out vibration suppression of the *** engineering scenarios,co-frequency vibration faults are highlighted by rotational frequency and are difficult to identify,and existing intelligent methods require more hardware conditions and are exclusively ***,Lightweight-convolutional neural networks(LW-CNN)algorithm is proposed in this paper to achieve real-time fault *** critical parameters are discussed and verified by simulated and experimental signals for the sliding window data augmentation *** on LW-CNN and data augmentation,the real-time intelligent diagnosis of co-frequency is ***,a real-time detection method of fault diagnosis algorithm is proposed for data acquisition to fault *** is verified by experiments that the LW-CNN and sliding window methods are used with high accuracy and real-time performance.

关键词： Co-frequency vibration Real-time diagnosis LW-CNN Data augmentation

Intelligent ion gels: Design, performance, and applications

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SmartMat 2024年第1期5卷 38-58页

作者： Naiwei Gao Caofeng pan Beijing Key Laboratory of Micro‐nano Energy and Sensor CAS Center for Excellence in NanoscienceBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijingChina Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education Center for Stretchable Electronics and Nano SensorsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijingChina

Intelligent ion gels,which possess highly tunable mechanical,electrical,and stimulus‐responsive properties,have emerged as powerful candidates in the field of artificial intelligence,telemedicine,and health *** enrich the functionality of ion gels,it is critical to explore the link between the structure and function of ion *** this review,we provide an overview of the synthesis path and functional derivatives of ion *** conformational relationships of ion gels have been discussed,such as the effect of structure on electrical conductivity as well as sensing *** the perspective of stimulus response,the role of ion gels in areas such as bionic haptics,neural devices,artificial muscles,and intelligent displays has also been *** is possible that smart ion gels will open up a new horizon in the upcoming smart era,especially after the current challenges are resolved.

关键词： chemical structure intelligent electronics ion gels stimulus‐responsive

A reduced-order model for fast predicting ionized flows of hypersonic vehicles along flight trajectory

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Chinese Journal of Aeronautics 2024年第1期37卷 89-105页

作者： Jingchao ZHANG Chunsheng NIE Jinsheng CAI Shucheng pan School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing 100076China Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China

An improved Reduced-Order Model(ROM)is proposed based on a flow-solution preprocessing operation and a fast sampling strategy to efficiently and accurately predict ionized hypersonic *** ROM is generated in low-dimensional space by performing the Proper Orthogonal Decomposition(POD)on snapshots and is coupled with the Radial Basis Function(RBF)to achieve fast prediction ***,due to the disparate scales in the ionized flow field,the conventional ROM usually generates spurious negative ***,this issue is addressed by performing flow-solution preprocessing in logarithmic space to improve the conventional ***,extra orthogonal polynomials are introduced in the RBF interpolation to achieve additional improvement of the prediction *** addition,to construct high-efficiency snapshots,a trajectory-constrained adaptive sampling strategy based on convex hull optimization is *** evaluate the performance of the proposed fast prediction method,two hypersonic vehicles with classic configurations,i.e.a wave-rider and a reentry capsule,are used to validate the proposed *** two cases show that the proposed fast prediction method has high accuracy near the vehicle surface and the free-stream region where the flow field is *** with the conventional ROM prediction,the prediction results are significantly improved by the proposed method around the discontinuities,*** shock wave and the ionized *** a result,the proposed fast prediction method reduces the error of the conventional ROM by at least 45%,with a speedup of approximately 2.0×105compared to the Computational Fluid Dynamic(CFD)*** test cases demonstrate that the method developed here is efficient and accurate for predicting ionized hypersonic flows.

关键词： Reduced-order model Radial basis function Constrained sampling Transfer function Fast flow prediction Ionized hypersonic flows

Microstructure and Mechanical Property of the Large Cross-Sectioned Mg-Gd-Y-Zn-Zr Alloy Produced by Small Extrusion Ratio

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 999-1006页

作者： Sen Wang Hucheng pan Caixia Jiang Zhihao Zeng Zhen pan Weineng Tang Chubin Yang Yuping Ren Gaowu Qin Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) College of Materials Science and EngineeringNortheastern UniversityShenyang110819China Mg and Mg Alloy Institute Technology CenterBaosteel Metal Co.LtdChina Baowu Steel GroupShanghai200940China Jiangxi Provincial Engineering Research Center for Magnesium Alloy Gannan Normal UniversityGanzhou341000China

In this work,the microstructure and mechanical properties of large cross-sectioned Mg-9Gd-3Y-1.2Zn-0.5Zr(VWZ931)samples produced by the small extrusion ratio has been *** as-extruded VWZ931 sample with diameter of~30 mm can exhibit the high yield strength(YS)of 339 MPa,ultimate tensile strength(UTS)of 387 MPa and elongation of 8.2%,*** peak-aged,the YS and UTS of the Mg samples were significantly increased to 435 MPa and 467 *** small extrusion ratio leads to the low fraction of dynamic recrystallized(DRX)grains in VWZ931 sample,and the texture hardening effect can be fully utilized to achieve high *** combined effect of precipitation strengthening due to the long-period stacking ordered phases and theβ′phase,grain boundary strengthening due to the fine DRX grains,heterogeneous deformation-induced strengthening caused by bimodal microstructure,can together contribute to the high strength of present Mg *** findings can shed light on designing other large-sized Mg wrought alloys with high mechanical performance.

关键词： Mg-RE alloy Mechanical property Bimodal grains Texture hardening

Hematopoietic aging:Cellular,molecular,and related mechanisms

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Chinese Medical Journal 2024年第11期137卷 1303-1312页

作者： Li Ye Chuan Tian Ye Li Hang pan Jinxiu Hu Liping Shu Xinghua pan The Stem Cells and Immune Cells Biomedical Techniques Integrated Engineering Laboratory of State and Regions Cell Therapy Technology Transfer Medical Key Laboratory of Yunnan ProvinceKunming Key Laboratory of Stem Cell and Regenerative MedicineBasic Medical Laboratory920th Hospital of Joint Logistics Support ForcePLAKunmingYunnan 650032China Department of Immunology of School of Basic Medicine of Guizhou Medical University National and Local Joint Engineering Laboratory of Cell Engineering Biomedical TechnologyKey Laboratory of Regenerative Medicine of Guizhou ProvinceState Key Laboratory of Efficacy and Utilization of Medicinal Plants Co-constructed by Province and MinistryKey Laboratory of Translational Research of Adult Stem Cell of Chinese Academy of Medical SciencesGuiyangGuizhou 550025China

Aging is accompanied by significant inhibition of hematopoietic and immune system function and disruption of bone marrow ***-related alterations in the inflammatory response,immunity,and stem cell niches are at the root of hematopoietic *** the molecular mechanisms underlying hematopoietic and bone marrow aging can aid the clinical treatment of aging-related *** particular,it is unknown how the niche reprograms hematopoietic stem cells(HSCs)in an age-dependent manner to maintain normal hematopoiesis in elderly ***,specific inhibitors and blood exchange methods have been shown to reshape the hematopoietic niche and reverse hematopoietic ***,we present the latest scientific discoveries related to hematopoietic aging and hematopoietic system rejuvenation,discuss the relationships between hematopoietic niche aging and HSC aging,and describe related studies on stem cell-mediated regulation of hematopoietic aging,aiming to provide new ideas for further study.

关键词： Stem cells Hematopoietic stem cell Niche Hematopoietic aging

Determination method of mesh size for numerical simulation of blast load in near-ground detonation

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Defence Technology（防务技术） 2024年第8期38卷 111-125页

作者： Doudou Si Zuanfeng pan Haipeng Zhang College of Civil Engineering Tongji UniversityShanghai 200092China State Key Lab of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

In order to improve the overall resilience of the urban infrastructures, it is required to conduct blast resistant design for important building structures in the city. For complex terrain in the city, it is recommended to determine the blast load on the structures via numerical simulation. Since the mesh size of the numerical model highly depends on the explosion scenario, there is no generally applicable approach for the mesh size selection. An efficient method to determine the mesh size of the numerical model of near-ground detonation based on explosion scenarios is proposed in this study. The effect of mesh size on the propagation of blast wave under different explosive weights was studied, and the correlations between the mesh size effect and the charge weight or the scaled distance was described. Based on the principle of the finite element method and Hopkinson-Cranz scaling law, a mesh size measurement unit related to the explosive weight was proposed as the criterion for determining the mesh size in the numerical simulation. Finally, the applicability of the method proposed in this paper was verified by comparing the results from numerical simulation and the explosion tests and was verified in AUTODYN.

关键词： Blast load Mesh size effect Numerical simulation Scaled mesh size Verification

Emergency rescue of a patient with hemorrhagic shock caused by superior mesenteric artery rupture:A case report

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World Journal of Clinical Cases 2024年第18期12卷 3567-3574页

作者： Xian-Ping Lin Xin-Li Guo He-Feng Tian Zheng-Rong Wu Wei-Jie Yang hong-Ying pan Nursing Department Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310020Zhejiang ProvinceChina Department of General Surgery Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310020Zhejiang ProvinceChina Department of Obstetrics and Gynecology Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310020Zhejiang ProvinceChina

BACKGROUND Superior mesenteric artery(SMA)injuries rarely occur during blunt abdominal injuries,with an incidence of35 beats/min),and blood pressure as low as 20/10 mmHg(1 mmHg=0.133 kPa).Computed tomography revealed abdominal and pelvic hematocele effusion,suggesting active *** patient was suspected of partial rupture of the distal SMA *** patient underwent emergency mesenteric artery ligation,scalp suture,and liver laceration *** view of conditions with acute onset,rapid progression,and high bleeding volume,key points of nursing were conducted,including activating emergency protocol,opening of the green channel,and arranging relevant examinations with various medical staff for quick *** seamless collaboration of the multidisciplinary team helped shorten the preoperative preparation *** laparotomy exploration and mesenteric artery ligation were performed to mitigate hemorrhagic shock while establishing efficient venous accesses and closely monitoring the patient’s condition to ensure hemodynamic *** measures were taken to avoid intraoperative hypothermia and *** After 3.5 h of emergency rescue and medical care,bleeding was successfully controlled,and the patient’s condition was ***,the patient was transferred to the intensive care unit for continuous mon

关键词： Superior mesenteric artery Hemorrhagic shock Arterial ligation Emergency nursing Case report