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Macro-micro dynamic behaviors and fracture modes of roll bonded 7A52/7A01/7B52 aluminum laminates in high velocity deformation

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Progress in Natural Science:Materials International 2018年第4期28卷 510-519页

作者： Guochuan Zhu Shuhui huang Xiwu Li Zhihui Li Youzhi Tong yongan Zhang Baiqing Xiong State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals Northeast light alloy Limited Liability Company Heilongjiang

Damage tolerance improvement in the lamination of aluminum alloy plates and composites has been reported in many studies. In the present study the macro-micro dynamic deformation behavior and related mechanisms of 7A52/7A01/7B52 laminated plates processed by hot roll bonding of 7A52, 7A01 and 7B52 plate at high strain rates and quasi-static compression has been investigated. The microstructure of the laminated plates was examined with backscatter diffraction(EBSD) techniques, scanning and transmission electron microscopies. The results showed that with increased strain rate, obvious strain rate hardening was observed in the single layer specimens. The peak flow stress of the multilayer samples was slightly higher than that of the 7A52 monolayer samples and much lower than that of the 7B52 monolayer samples at the same strain rate. Beyond the peak stress state, the strain hardening was replaced by thermal softening in the 7A52 layer, leading to low resistance of deformation and high tendency to facilitate deformation-induced adiabatic shear bands(ASBs) that consist of dynamic recrystallized grains. ASBs in laminated samples were deflected and bifurcated at the interface of 7A52 layer. In addition, bifurcated ASBs converged at the interface between the 7A52 and 7A01 layers. The high deformation resistance observed in the laminate under dynamic loading was a consequence of the high capacity for strain hardening in the 7A01 layer. This hardening effectively overcame the influences of thermal softening and dynamic recovery during dynamic loading. This study provides an understanding of the laminate’s microstructure evolution during dynamic deformation and its relevance to the fracture modes of a multilayer structure under dynamic loading.

关键词： Laminated plate Fracture mode Microstructure Aluminum alloy Mechanical properties

颈动脉内膜切除治疗症状性颈动脉狭窄的早期疗效

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武警医学 2011年第3期22卷 192-194页

作者：张宝国尹震马宏伟黄永安程钢戈董连强空军总医院神经外科北京100142

目的总结应用颈动脉内膜切除术(carotid endarterectomy,CEA)治疗症状性颈动脉狭窄的早期疗效与经验。方法对35例颈动脉狭窄患者实施了颈动脉内膜切除术,其中1例同期进行了椎动脉内膜切除术。所有病例经血管数字减影血管造影检查证实为... 详细信息

目的总结应用颈动脉内膜切除术(carotid endarterectomy,CEA)治疗症状性颈动脉狭窄的早期疗效与经验。方法对35例颈动脉狭窄患者实施了颈动脉内膜切除术,其中1例同期进行了椎动脉内膜切除术。所有病例经血管数字减影血管造影检查证实为颈动脉狭窄。早期13例采用全麻插管,后期22例采用局部麻醉。颈总动脉阻断时间30～55 min[平均(45±10.23)min]。结果术后30 d无死亡和卒中发生。术后出现舌下神经损伤1例,喉返神经损伤1例,面神经下颌缘支损伤2例,均为短暂的轻度损伤。结论颈动脉内膜切除术是治疗症状性颈动脉狭窄安全、有效的方法。

关键词：缺血性脑卒中颈动脉内膜切除术颈动脉狭窄

Microbial and molecular fossils from the Permian Zoophycos in South China

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Science China Earth Sciences 2007年第8期50卷 1121-1127页

作者： GONG YiMing XU Ran XIE ShuCheng huang XianYu HU Bin QI yongan ZHANG GuoCheng Key Laboratory of Biogeology and Environmental Geology of Ministry of Education State Key Laboratory of Geological Processes and Mineral ResourcesChina University of GeosciencesWuhan 430074China Institute of Resources and Environment Key Laboratory of Biogenic Traces&Sedimentary Minerals of Henan ProvinceHenan Polytechnic UniversityJiaozuo 454003China

The trace fossil Zoophycos was enriched in the lower part of the Guadalupian Maokou Formation of Permian in Laibin, Guangxi of South China, and characterized by observable lamellae within its spreiten. Associated with these lamellae are the prolific coccus- and spirillum-shaped microbe fossils. These microbes morphologically identified are 0.4―3.0 μm in diameter or length. Molecular fossils, including normal alkanes (dominated by C18, without an odd-over-even predominance), acyclic isoprenoids (such as pristane (Pr) and phytane (Ph)), extended tricyclic terpanes, pentacyclic triterpanes, steranes, al-kylcyclohexanes, dibenzothiophenes, benzonaphthothiophenes, benzobisbenzothiophenes, were in-strumentally identified in the wackestone characterized by the occurrence of abundant Zoophycos (composite ichnofabric indices are 4) and crowded microbial fossils. The value of the Pr/Ph ratio is less than 1, indicative of a dysoxic condition. The identification of abundant sulfur compounds (the thio-phene series) related to the contribution of reductive sulfur favors the occurrence of sulphate-reducing bacteria. The association of abundant microbial colonies with microbial molecular fossils within the spreiten suggests that trace fossils Zoophycos would be a multifunctional garden carefully constructed by the Zoophycos-producer, where different microbial colonies were orderly and carefully planted and cultured in different minor lamellae within spreiten. Hence, it is proposed that the Zoophycos-producer symbiosed with microbial colonies on the mutual basis of food supply and the redox conditions.

关键词： trace fossils Zoophycos microbes molecular fossils Permian South China

Intelligent Edge Network Routing Architecture with Blockchain for the IoT

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China Communications 2023年第11期20卷 151-163页

作者： yongan Guo Yuao Wang Qijie Qian College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Engineering Research Center of Health Service System Based on Ubiquitous Wireless Networks Ministry of EducationNanjing 210003China Edge Intelligence Research Institute Nanjing University of Posts and TelecommunicationsNanjing 210003China

The demand for the Internet of Everything has slowed down network routing ***-tional routing policies rely on manual configuration,which has limitations and adversely affects network *** this paper,we propose an Inter-net of Things(IoT)Intelligent Edge Network Routing(ENIR)*** uses deep reinforcement learning(DRL)to simulate human learning of empir-ical knowledge and an intelligent routing closed-loop control mechanism for real-time interaction with the network *** to the network de-mand and environmental conditions,the method can dynamically adjust network resources and perform in-telligent routing *** uses blockchain tech-nology to share network knowledge and global op-timization of network *** intelligent rout-ing method uses the deep deterministic policy gradient(DDPG)*** simulation results show that ENIR provides significantly better link utilization and transmission delay performance than various routing methods(e.g.,open shortest path first,routing based on Q-learning and DRL-based control framework for traffic engineering).

关键词： blockchain deep reinforcement learning edge intelligence intelligent routing IoT

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徒手脑室插管精确性分析

武警医学 2012年第1期23卷 41-43,48页

作者：张宝国马宏伟黄永安张晖程钢戈董连强空军总医院神经外科北京100142

目的分析徒手经额脑室插管(ventricular catheter,VC)的精确性。方法回顾性分析自2002-05至2010-11空军总医院神经外科130例患者146侧徒手VC术后CT影像9,8例为脑室腹腔或心房分流术3,2例为脑室外引流置管。为了评估插管尖位置,笔者使用... 详细信息

目的分析徒手经额脑室插管(ventricular catheter,VC)的精确性。方法回顾性分析自2002-05至2010-11空军总医院神经外科130例患者146侧徒手VC术后CT影像9,8例为脑室腹腔或心房分流术3,2例为脑室外引流置管。为了评估插管尖位置,笔者使用改良的Kakarla分级方法:1级,位于Monro孔前侧脑室额角内;2级,位于除同侧额角外的侧脑室或三脑室内,具有引流功能;3级,位于脑实质内或非靶点脑脊液间隙内,有或无引流功能。结果理想放置1级45个(30.8%);2级85个(58.2%);3级16个(11.0%)。结论徒手VC放置是一个不精确的操作,还有很大的改进空间。发明一个易用、方便的影像引导系统可能会保证VC的精确放置。

关键词：脑室插管精确性分级脑积水

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慢性硬膜下血肿位置与颅骨形态的关系

武警医学 2012年第12期23卷 1065-1067,1071页

作者：张宝国马宏伟黄永安张晖程钢戈董连强空军总医院神经外科北京100142

目的探讨慢性硬膜下血肿(chronic subdural hematoma,CSDH)位置与枕部颅骨形态的关系。方法对98例经历CSDH手术患者的头颅CT/MRI影像进行回顾,对颅骨的对称性和CSDH的位置进行分析。结果患者平均(71.00±13.96)岁(37～93岁)。枕部颅骨... 详细信息

目的探讨慢性硬膜下血肿(chronic subdural hematoma,CSDH)位置与枕部颅骨形态的关系。方法对98例经历CSDH手术患者的头颅CT/MRI影像进行回顾,对颅骨的对称性和CSDH的位置进行分析。结果患者平均(71.00±13.96)岁(37～93岁)。枕部颅骨对称患者37例,不对称61例。在不对称颅骨扁平位于右侧的有41例,位于左侧的有20例。CSDH为双侧患者20例,单侧78例,单侧血肿中30例位于右侧,48例位于左侧。双侧CSDH在枕部颅骨对称者较不对称者更为普遍,差异具有统计学意义(P=0.021)。在61例枕部颅骨不对称者中,CSDH双侧8例,在其余的53例患者中,CS-DH位于枕部颅骨扁平对侧的有37例,而位于扁平同侧的有16例。结论双侧CSDH常发生在枕部颅骨对称的患者,而在枕部颅骨不对称的患者,CSDH通常位于枕部颅骨扁平侧的对侧。

关键词：慢性硬膜下血肿颅骨形态学颅顶计算机断层扫描硬膜边缘细胞

Service-Oriented Network Virtualization Architecture for Internet of Things

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China Communications 2016年第9期13卷 163-172页

作者： yongan Guo Hongbo Zhu Longxiang Yang College of Telecommunications&Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Key Lab of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China

As a key technology to realize smart services of Internet of Things（IoT）, network virtualization technology can support the network diversification and ubiquity, and improve the utilization rate of network resources. This paper studies the service-ori- ented network virtualization architecture for loT services. Firstly the semantic description method for loT services is proposed, then the resource representation model and resource management model in the environment of network virtualization are presented. Based on the above models, the service-oriented virtual network architecture for loT is established. Finally, a smart campus system is designed and deployed based on the service-oriented virtual network architecture. Moreover, the proposed architecture and models are verified in experiments.

关键词： Internet of Things network virtualization virtual network resource management virtual network embedding

Solvent effects on the measured bubble-point pressures and pseudo bubble-point pressures of different heavy crude oil-solvent systems

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Petroleum 2022年第4期8卷 577-586页

作者： Jiangyuan Yao Wei Zou yongan Gu Petroleum Technology Research Centre(PTRC) Petroleum Systems EngineeringFaculty of Engineering and Applied ScienceUniversity of ReginaReginaS4S 0A2Canada

In this paper,the bubble-point pressures and pseudo bubble-point pressures of various heavy crude oil-solvent systems were measured and studied by conducting the constant-composition-expansion(CCE)tests,during which the test pressure was depleted in a stepwise manner.A total of fourteen CCE tests were performed for five heavy crude oil-CO_(2)systems,four heavy crude oil-CH_(4)systems,and five heavy crude oil-C_(3)H_(8)systems,*** the CCE tests were conducted by using a pressure-volume-temperature(PVT)*** was found that for most heavy crude oil-solvent systems with relatively low solvent concentrations,the measured PVT cell pressure *** volume(Pcell-nmix)data in the CCE tests had three distinct regions,which were one-liquid phase region(Regions I),foamy-oil region(Region II)and two-phase region(Region III).Accordingly,the PVT cell pressure at the intersection point of Regions I and II was referred to as the measured bubble-point pressure,whereas the PVT cell pressure at the intersection point of Regions II and III was termed as the measured pseudo bubble-point *** some heavy crude oil-solvent systems with high solvent concentrations,however,the measured Pcell-nmix data may have two regions *** this special case,the PVT cell pressure at the intersection point of the two regions was considered as the measured bubble-point pressure and no pseudo bubble-point pressure could be *** was also found that the heavy crude oil-CH_(4)system had not only the highest bubble-point pressure and pseudo bubble-point pressure but also the largest difference between the bubble-point pressure and pseudo bubble-point pressure,in comparison with the heavy crude oil-CO_(2)system and the heavy crude oil-C_(3)H_(8)system at the same solvent *** facts indicate that CH_(4)not only is the most volatile solvent but also can remain as dispersed gas bubbles to induce the most stable foamy oil in the largest pressure range after it is nucl

关键词： Heavy crude oil-solvent systems Phase behaviours PVT studies Constant-composition-expansion(CCE)tests Bubble-point pressure Pseudo bubble-point pressure

Effects of different protein and lipid levels on the growth performance and intestinal microflora of loach(Paramisgurnus dabryanus)

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Animal Nutrition 2023年第2期13卷 229-239页

作者： Zirui Wang Shuyao Li Qiubai Zhou Jinhua Zhang yongan Li Youjie Li Zhiwen Yuan Guanghua huang College of Animal Science and Technology Jiangxi Agricultural UniversityNanchang 330045China Key Laboratory of Featured Hydrobios Nutritional Physiology and Healthy Breeding Nanchang330045China

The aim of this study was to examine the effects of dietary protein and lipid levels on the growth per-formance and homeostasis of the intestinal flora in Paramisgurnus *** 8-week 3×3 two-factorial experiment was conducted to investigate the interaction between dietary crude protein(CP:30%,35%,40%)and ether extract(EE:6%,10%,14%)on the growth rate and the intestinal microflora of ***.A total of 2,160 fish(5.19±0.01 g)were randomly allotted to 36 aquariums each with 60 *** were fed the experimental diet twice *** revealed that weight gain rate(WGR),specific growth rate(SGR),protein efficiency ratio and net protein utilization significantly increased when increasing protein levels from 30%to 40%(P<0.05).Both WGR and SGR enhanced first but reduced thereafter with maximum value at 10%lipid level as dietary lipid increased from 6%to 14%(P<0.05).Significant interactions between protein and lipid were found with feed conversion rate,lipid efficiency ratio and net lipid utilization(P<0.05).At the phylum level,Proteobacteria and Actinobacteria were the dominant bacteria;at the genus level,Burkholderia-Caballeronia-Paraburkholderia was the dominant *** fed the diet containing 10%lipid had a higher abundance of Proteobacteria and unclassi-fied_f_Eenterobacteriaceae than those fed the 14%lipid diet,and a higher abundance of Rhodobacter than those fed the 6%lipid diet(P<0.05).Analysis of the predicted functions showed that metabolism in the intestine of fish in the CP40EE10 group was more active than that in CP30EE14 *** regression analysis found that a diet containing 40.87%protein and 9.88%lipid can be considered optimal for ***.

关键词： Paramisgurnus dabryanus Protein/lipid ratio Growth performance Feed utilization Intestinal microflora