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China Foundry 2014年第1期11卷 14-19页

作者： Li Xinlei Hao Qitang miao xiaochuan Fan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an Chaoma Technology Company Limited

To investigate the influence of Centrifugal Counter-gravity Casting(C3) process on the solidification microstructure and mechanical properties of the casting, A357 aluminum alloy samples were produced by different process conditions under C3. The results show that C3 has better feeding capacity compared with the vacuum suction casting; and that the mechanical vibration and the convection of melts formed at the centrifugal rotation stage suppress the growth of dendrites, subsequently resulting in the refinement of grains and the improvement of mechanical properties, density and hardness. A finer grain and higher strength can be obtained in the A357 alloy by increasing centrifugal radius and rotational speed. However, casting defects will appear near the rotational axis and the mechanical properties will decrease once the rotational speed exceeds 150 r·min-1.

关键词： centrifugal counter-gravity casting vacuum suction casting rotational speed solidification feeding

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英国官产学研合作模式及其借鉴作用初探

情报工程 2015年第1期1卷 49-56页

作者：张红苗润莲蔚晓川北京市科学技术情报研究所北京100044

英国的产学研合作自始就得到了政府重视和推动,具有很浓的官方色彩,官产学研合作对推动英国科技创新和经济发展发挥了重要作用。本文通过文献分析和对比研究方法,对英国官产学研合作进行了总体梳理,分析研究了具体的合作模式及其评价,... 详细信息

英国的产学研合作自始就得到了政府重视和推动,具有很浓的官方色彩,官产学研合作对推动英国科技创新和经济发展发挥了重要作用。本文通过文献分析和对比研究方法,对英国官产学研合作进行了总体梳理,分析研究了具体的合作模式及其评价,并以英国经验为借鉴,结合我国创新体系建设目标,从政策环境和资助力度,合作园区和合作交流平台建设,科技中介机构培育与发展以及人才培养与交流等四方面提出我国加强产学研合作的建议,以期对我国官产学研合作机制的完善,为政府在科技创新中更有效地发挥推动引导作用提供借鉴参考。

关键词：战略管理科技情报科研选题企业市场营销

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威28井强排水效果分析及今后工作设想

天然气工业 1986年第1期6卷 69-72页

作者：华东涛刘凯王小川缪力波四川石油管理局川西南矿区

威28井的气举强排水采气试验取得显著成效,为改善气藏的水侵程度、恢复产能、提高最终采收率,提供了新的途径。文章介绍了该项试验的工艺设计,动志及效果分析,提出了在全气藏建立气举强排水系统,开展主产区排水采气的设想。

关键词：强排水威远气田气举人工举升排水采气日产气量效果分析

On the correlation of the local OVII and OVI absorption lines in the spectra of active galactic nuclei

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Science China(Physics,Mechanics & Astronomy) 2016年第11期59卷 83-84页

作者： miao Wang Taotao Fang xiaochuan Jiang Departmen of Astronomy and Institute of Theoretical Physics and Astrophysics Xiamen University

Dear Editors,Active Galactic Nuclei（AGNs）are very effective tools to study the environment both intrinsic to the central black holes of galaxies[1],or absorbing gas distributed along the sight ***,numerous highly ionized,local（z=0）metal absorption lines were detected in the X-ray spectra of background AGNs[2],providing an important method in probing hot gas and its content in and around our Galaxy.

关键词：活动星系核光谱检测吸收线星系中心热气体 AGN X射线银河系

When treating acute ischaemic stroke of LVO type,time window prevails over tissue window

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Stroke & Vascular Neurology 2024年第5期9卷 461-463页

作者： xiaochuan Huo Aoming Jin Zhongrong miao Yongjun Wang David Wang Neurological Disease Center Cerebral Vascular Disease DepartmentBeijing An Zhen HospitalBeijingChina Department of Neurology Beijing Tiantan HospitalBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Interventional Neuroradiology Department of NeurologyBeijing Tiantan HospitalBeijingChina Petznick Stroke Center Barrow Neurological InstitutePhoenixArizonaUSA

Time is *** fast an occluded cerebral artery can be reopened is directly related to how many brain cells can be *** iden-tification of a tissue window as indicated by the presence of a penumbra on multimodality imaging study has opened the time window of treatment to 24 hours after the onset.1 From 2019 to 2022,the issue of direct intra-arterial(IA)mechanical thrombectomy(MT)is non-inferior to bridging therapy or not has been settled.2 Bridging therapy may have slight advantage in re-opening the occluded arteries than direct IA MT.3 Recently published data on IA MT to treat acute ischaemic stroke(AIS)from a large vessel occlusion but with a low Alberta Stroke Programme Early CT(ASPECT)score indicated that in these patients,performing a multimodality imaging study may not be *** imaging study including MRI of head,MRA of head and neck and magnetic resonance perfusion(MRP)of head or CT of head,CTA of head and neck and CT perfusion(CTP)of head are must-to do tests when evaluating patients with AIS with an onset time between 6 and 24 hours in current clinical practice.

关键词： acute perfusion cerebral

Safety and efficacy of oral antiplatelet for patients who had acute ischaemic stroke undergoing endovascular therapy

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Stroke & Vascular Neurology 2021年第2期6卷 230-237页

作者： xiaochuan Huo Raynald Jing Jing Anxin Wang Dapeng Mo Feng Gao Ning Ma Yilong Wang Yongjun Wang Zhongrong miao Neurointervention center Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Center of Stroke Beijing Institute for Brain DisordersBeijingChina Beijing Tiantan Hospital BeijingChina Neurointervention center Beijing Tiantan HospitalBeijingChina

Background and purpose To investigate the safety and efficacy of oral antiplatelet therapy(APT)for patients who had acute ischaemic stroke(AIS),receiving endovascular therapy(EVT).Methods Patients were divided into non-APT group and APT(single APT or dual APT(DAPT)*** safety and efficacy endpoints at 3-month follow-up were symptomatic intracranial haemorrhage(sICH),recanalisation rate,clinical outcome and *** Among 915 patients who had AIS,those in APT group(n=199)showed shorter puncture-to recanalisation time,lower frequency of intravenous thrombolysis and more use of tirofiban compared with those in non-antiplatelet group(n=716)(p<0.05 for all).Oral APT was found to be associated with superior clinical outcome compared with non-APT(APT(44.2%)versus non-APT(41.1%)),adjusted OR=2.605,95% CI 1.244 to 5.455,p=0.011).DAPT showed superior clinical outcome compared with non-APT(DAPT(56.5%)versus non-APT(41.1%),adjusted OR=5.405,95% CI 1.614 to 18.102,p=0.006)and lower risk of mortality at 3-month follow-up(DAPT(4.8%)versus non-DAPT(17.7%),adjusted OR=0.008,95%CI 0.000 to 0.441,p=0.019).There was no significant difference in sICH between the two *** Oral APT prior to undergoing EVT is safe and may accompany with superior clinical *** may associate with superior clinical outcomes and lower risk of mortality.

关键词： mortality patients acute

Differential flatness-based distributed control of underactuated robot swarms

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Applied Mathematics and Mechanics(English Edition) 2023年第10期44卷 1777-1790页

作者： Ningbo AN Qishao WANG xiaochuan ZHAO Qingyun WANG Department of Dynamics and Control Beihang UniversityBeijing 100191China Institute of Computer Application Technology China North Industries Group Corporation LimitedBeijing 100095China

This paper proposes a distributed control method based on the differential flatness(DF) property of robot swarms. The swarm DF mapping is established for underactuated differentially flat dynamics, according to the control objective. The DF mapping refers to the fact that the system state and input of each robot can be derived algebraically from the flat outputs of the leaders and the cooperative errors and their finite order derivatives. Based on the proposed swarm DF mapping, a distributed controller is designed. The distributed implementation of swarm DF mapping is achieved through observer design. The effectiveness of the proposed method is validated through a numerical simulation of quadrotor swarm synchronization.

关键词： differential flatness(DF) underactuated robot distributed control synchronization

Natural and human-induced decline and spatio-temporal differentiation of terrestrial water storage over the Lancang-Mekong River Basin

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Journal of Geographical Sciences 2025年第1期 112-138页

作者： CHEN Junxu WANG Yuan ZHAO Zhifang FAN Yunjiang LUO xiaochuan YI Lu FENG Siqi YANG Liang Emlyn Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Yunnan University International Joint Research Center for Karstology Yunnan University School of Engineering Westlake University Department of Geography Ludwig Maximilian University of Munich (LMU)

Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB), the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified. This work investigated LMRB's terrestrial water storage anomaly(TWSA) and its spatio-temporal dynamics during 2002–2020. Considering the effects of natural factors and human activities, the respective contributions of climate variability and human activities to terrestrial water storage change(TWSC) were separated. Results showed that:(1) LMRB's TWSA decreased by 0.3158 cm/a.(2) TWSA showed a gradual increase in distribution from southwest of MRB to middle LMRB and from northeast of LRB to middle LMRB. TWSA positively changed in Myanmar while slightly changed in Laos and China. It negatively changed in Vietnam, Thailand and Cambodia.(3) TWSA components decreased in a descending order of soil moisture, groundwater and precipitation.(4) Natural factors had a substantial and spatial differentiated influence on TWSA over the LMRB.(5) Climate variability contributed 79% of TWSC in the LMRB while human activities contributed 21% with an increasing impact after 2008. The TWSC of upstream basin countries was found to be controlled by climate variability while Vietnam and Cambodia's TWSC has been controlled by human activities since 2012.

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Endovascular revascularisation of acute tandem vertebrobasilar artery occlusion:seven case series with literature reviews

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Stroke & Vascular Neurology 2018年第1期3卷 17-21页

作者： Haihua Yang Ning Ma Shiyong Zhang xiaochuan Huo Feng Gao Xuan Sun Dapeng Mo Zhongrong miao Department of Interventional Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Neurology Beijing Daxing HospitalCapital Medical UniversityBeijingChina Department of Interventional Neurology Beijing Fengtai Youanmen HospitalBeijingChina

background The outcome of acute ischaemic stroke due to tandem vertebrobasilar artery occlusion was *** revascularisation may be a positive approach for acute basilar artery occlusion combined with vertebral ostium stenosis or *** reported seven patients with acute vertebrobasilar tandem occlusion by using angioplasty or stenting for proximal lesion and thrombectomy for distal *** and methods Consecutive patients with acute tandem vertebrobasilar artery occlusion at two centres were included in this *** retrospectively analysed the clinical,technical and functional outcomes of the *** From March 2016 to March 2017,seven patients were *** mean age and National Institute of Health Stroke Scale score at admission was 57 years and 22,respectively.A reverse approach was used in five *** Thrombolysis in Cerebral Infarction score 2b-3 was acquired in all *** were no procedural *** modified Rankin Scale score was 1-2 for three patients and 4 for one patient at 3 *** patients died at 3 months of *** Endovascular revascularisation may be feasible for acute tandem vertebrobasilar artery occlusion,and more researches are needed.

关键词： occlusion acute vertebrobasilar

Acute Ischaemic Stroke Cooperation Group of Endovascular Treatment (ANGEL) registry: study protocol for a prospective, multicentre registry in China

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Stroke & Vascular Neurology 2019年第1期4卷 57-60页

作者： xiaochuan Huo Ning Ma Dapeng Mo Feng Gao Ming Yang Yilong Wang Yongjun Wang Zhongrong miao ANGEL investigators Neurointervention Center Beijing Tiantan HospitalBeijingChina Department of Interventional Neurology Beijing Tiantan HospitalBeijingChina Neurology Beijing Tiantan HospitalBeijingChina

Background and purpose Endovascular treatment could improve functional outcomes and reduce mortality in patients with intracranial large artery occlusion. This registry aims to evaluate the endovascular treatment delivery and to improve endovascular treatment algorithm in clinical practice for patients with stroke in China. Methods and analysis This multicentric, nationwide, prospective registry plans to include 20 stroke centres and recruit 900 consecutive AIS patients with large- artery occlusion under endovascular treatment. This registry will enrol acute large vessel occlusion patients suitable for endovascular treatment and the inclusion and exclusion criteria. In this study, 90 days functional independence (modified Rankin Scale score ≤2) is the primary efficacy endpoint. The procedural efficacy endpoint of this registry is target artery recanalisation defined by modified Thrombolysis in Cerebral Infarction score 2b or 3 after endovascular therapy. Symptomatic intracranial haemorrhage with 24±3 hours after the procedure is the primary safety endpoint of this registry. Ethics and dissemination Beijing Tiantan Hospital’s Ethics committee and all other participating centres approved the protocol and data collection of Acute Ischaemic Stroke Cooperation Group of Endovascular Treatment registry. Each participant or representative had a written informed consent.

关键词： prospective centre registry