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移动网络前向指针策略的鉴权管理研究

通信学报 2004年第9期25卷 140-145页

作者：江虹陆斌刘辉李乐民电子科技大学通信学院四川成都610054 四川联合通信有限公司四川成都610036 电子科技大学计算机学院四川成都610054

鉴权管理是移动通信移动管理中非常重要的技术,其策略的选择将直接影响网络中各网元的信令负荷。本文主要讨论移动通信系统前向指针位置管理策略中的鉴权管理。当用户在远离其HLR的不同VLR对应覆盖区域移动时,系统通过向其原VLR索取剩... 详细信息

鉴权管理是移动通信移动管理中非常重要的技术,其策略的选择将直接影响网络中各网元的信令负荷。本文主要讨论移动通信系统前向指针位置管理策略中的鉴权管理。当用户在远离其HLR的不同VLR对应覆盖区域移动时,系统通过向其原VLR索取剩余鉴权数据或向其HLR申请新鉴权数据来实现用户的鉴权管理。通过鉴权开销及被呼处理时延等指标的分析,本文提出的鉴权管理算法较适合于CMR较小的MS鉴权管理;当MS的CMR增大时,本文提出的鉴权管理算法与二层管理策略如GSM或IS-41移动系统的开销及时延等指标逐渐接近。

关键词：鉴权管理前向指针鉴权开销

Influence of oxide scales on the corrosion behaviors of B510L hot-rolled steel strips

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 769-778页

作者： Cheng Man Chao-fang Dong hui-bin Xue Kui Xiao Xiao-gang li hui-bin Qi Key Laboratory for Corrosion and Protection(MOE) University of Science and Technology BeijingBeijing 100083China Ningbo Institute of Material Technology and Engineering Chinese Academy of SciencesNingbo 315201China BaoSteel Group Technological Center Shanghai 201900China

The influence of oxide scales on the corrosion behaviors of B510 L hot-rolled steel strips was investigated in this study. Focused ion beams and scanning electron microscopy were used to observe the morphologies of oxide scales on the surface and cross sections of the hot-rolled steel. Raman spectroscopy and X-ray diffraction were used for the phase analysis of the oxide scales and corrosion products. The corrosion potential and impedance were measured by anodic polarization and electrochemical impedance spectroscopy. According to the results, oxide scales on the hot-rolled strips mainly comprise iron and iron oxides. The correlation between mass gain and test time follows a power exponential rule in the damp-heat test. The corrosion products are found to be mainly composed of γ-Fe OOH, Fe3O4, ？-Fe OOH, and γ-Fe2O3. The contents of the corrosion products are different on the surfaces of the steels with and without oxide scales. The steel with oxide scales is found to show a higher corrosion resistance and lower corrosion rate.

关键词： strip steel hot rolling focused ion beams Raman spectroscopy oxide scale corrosion

Does the long-term application of calcium superphosphate lead to an increase of the soil rare earth element contents？

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Journal of Environmental Sciences 2006年第1期18卷 130-134页

作者： ZHANG Yun DENG li-bin YE Wan-hui South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China School of Resources and Environmental Science Hubei University Wuhan 430062 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

In order to test whether the long-term application of calcium superphosphate leads to an increase of the soil rare earth element contents, superphosphate fertilized soils were sampled and compared with superphosphate-free soils. Spectrophlame inductively coupled argon plasma atomic emission spectrophotometer （ICP-AES） was applied to quantify the rare earth elements （REEs）. The total rare earth element contents in calcium superphosphate from Zhijin County, west part of Guizhou Province, China （produced by the sulphuric acid treatment of the apatites） are about 2.54 mg/g. Between 38 and 189 gREEs/hm^2 per year （available for plants, estimated by 2% citric acid） will be introduced into the soil solution when applying 320 kg superphosphate/hm^2 per year. The long-term application of the latter will increase the REE content by about 18% in the soil surface layer in these areas. A statistically significant increase of the content of the rare earths in some cultivated soils should not be neglected.

关键词： rare earth elements calcium superphosphate soil

Influence of Microstructural Evolution on the Hot Deformation Behavior of an Fe–Mn–Al Duplex lightweight Steel

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Acta Metallurgica Sinica(English Letters) 2018年第4期31卷 389-400页

作者： li-Xiong Xu hui-bin Wu Xin-Tian Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China National Engineering Research Center of Advanced Rolling University of Science and Technology Beijing Beijing100083China

The hot deformation behavior of Fe-26Mn-6.2A1-0.05C steel was studied by experimental hot compression tests in the temperature range of 800-1050℃ and strain rate range of 0.01-30 s-1 on a Gleeble-3500 thermal simulation *** microstructural evolution during the corresponding thermal process was observed in situ by confocal laser scanning *** backscattered diffraction and transmission electron microscopy analyses were carried out to observe the microstructural morphology before and after the hot ***,interrupted compression tests were conducted to correlate the microstructural characteristics and softening mechanisms at different deformation *** results showed that hot compression tests of this steel were all carried out on a duplex matrix composed of austenite and *** the deformation temperature increased from 800 to 1050℃,the volume fraction of austenite decreased from 70.9% to 44.0%,while that of 6-ferrite increased from 29.1% to 56.0%.Due to the different stress exponents（n）and apparent activation energies（Q）,the generated strain was mostly accommodated by δ-ferrite at the commencement of deformation,and then both dynamic recovery and dynamic recrystallization occurred earlier in δ-ferrite than in *** interaction of strain partitioning and unsynchronized softening behavior caused an abnormal hot deformation behavior profile in the Fe-Mn-A1 duplex steel,such as yield-like behavior,peculiar work-hardening behavior,and dynamic softening behavior,which are influenced by not only temperature and strain rate but also by microstructural evolution.

关键词： Microstructural evolution Dual-phase steel lightweight component Hot deformation Dynamic recrystallization

Effect of Microstructure on Corrosion Behavior of Mg–Sr Alloy in Hank's Solution

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Acta Metallurgica Sinica(English Letters) 2019年第3期32卷 305-320页

作者： Jia-hui Dong li-li Tan Yi-bin Ren Ke Yang Institute of Metal Research Chinese Academy of Science School of Materials Science and Engineering University of Science and Technology of China

Mg–Sr alloy has been studied as a potential biodegradable material with excellent bioactivity to promote the bone formation. However, its degradation behavior needs to be well controlled to avoid the negative effect, which is important for future application. Therefore in this study, the microstructure and its effect on corrosion behavior of an Mg–1.5 Sr alloy were investigated. The microstructures of the alloy under different processing procedures were characterized by both optical and scanning electron microscopes. The corrosion performance was studied in Hank's solution using immersion,potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) tests. The results showed that the grain size and the amount and distribution of b-Mg_(17)Sr_2 had obvious effects on the corrosion behavior of Mg–Sr alloy. The smaller the grain size was, the more the protective surface layer formed on Mg–Sr alloy, and the higher the corrosion resistance was. For the as-cast Mg–Sr alloy, the network-like second phases precipitated along the grain boundaries could not hinder the corrosion due to their own corrosion cracking accelerating the intergranular corrosion. However, the refinement of second phases increased the corrosion resistance of the as-extruded alloy. After solution treatment at 450 °C for 5 h, the grains in the alloy did not grow much and b-Mg_(17)Sr_2 phases homogenously distributed in the alloy, resulting in the increase in corrosion resistance. However, after aging treatment, large amount of precipitated second phases increased the galvanic corrosion of the alloy, accelerating the development of corrosion.

关键词： Mg–Sr alloy Microstructure Corrosion Extrusion Heat treatment

Lycopene exerts anti-inflammatory effect to inhibit prostate cancer progression

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Asian Journal of Andrology 2019年第1期21卷 80-85页

作者： li-Ning Jiang Ya-bin liu bing-hui li Department of Surgery II Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011China Department of Urology Surgery I Cangzhou Central Hospita Cangzhou 061000China

Lycopene is a natural compound that alleviates oxidative stress and inflammation,exerting therapeutic effects in a number of *** aim of this study is to investigate the efficacy of lycopene in inhibiting prostate *** viability assays indicated the dose-and time-dependent toxicity of lycopene in prostate cancer *** V/propidium iodide double-staining assays revealed the strong apoptotic effects of *** levels of inflammatory factors,including interleukin-1 (ILl),IL6,ILS,and tumor necrosis factor-α(TNF-α),in lycopene-treated cells were also reduced by lycopene *** the increasing dose of lycopene,the survival of mice bearing prostate cancer xenografts was significantly improved (P <0.01),and the tumor burden was significantly reduced (P <0.01).Our results indicate that lycopene is a promising chemotherapy drug,which inhibits prostate cancer progression by suppressing the inflammatory response.

关键词： dietary supplement inflammation lycopene prostate cancer

Refill Friction Stir Spot Welding of Similar and Dissimilar Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 30-42页

作者： Xiao-Song Feng Song-bin li li-Na Tang hui-Min Wang Shanghai Aerospace Equipments Manufacturer Co. LtdShanghai 200245China National Center for Materials Service Safety University of Science and TechnologyBeijingBeijing 100083China

Refi ll friction stir spot welding,also known as friction spot welding(FSpW),is a solid-state welding process suitable for spot joining of lightweight *** the eff orts of improving joint quality for similar and dissimilar materials,for example,aluminum and magnesium,this joining technology is well *** joining mechanism and process characteristics of FSpW have been widely ***,the application of FSpW in industry has not been entirely *** this review article,the research of similar and dissimilar material joints,such as,Al/Cu,Al/Ti,Al/Mg and Al/Steel,is *** microstructural features and mechanical properties of the joints,welding tool and the application development are discussed in detail.

关键词： Refill friction stir spot welding Dissimilar joints Microstructure Mechanical properties Welding parameters

Perspective of drug design with high-performance computing

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National Science Review 2021年第12期8卷 11-12页

作者： Zhe li hui li Kunqian Yu Hai-bin Luo Guangdong Provincial Key Laboratory of New Drug Design and Evaluation School of Pharmaceutical Sciences Sun Yat-Sen University State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology Shanghai Tech University Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical Sciences Hainan University

In recent decades, the development of high-performance computing(HPC)continues to follow Moore’s law, with many computational methods in drug design experiencing a *** prediction, virtual screening,molecular dynamics simulations and protein folding are crucial applications of computational drug design to accelerate drug discovery(Fig. 1). Reliable prediction of the receptor/ligand binding affinities that determine the pharmacological effects of drugs is the most important application of HPC in drug discovery, and is the main focus of this Perspective.

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三孔单向式法胸腔镜肺叶切除术治疗Ⅱ期非小细胞肺癌

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河南科技大学学报（医学版） 2017年第3期35卷 193-196页

作者：王辉斌李丹峰马军亮中信中心医院胸外科河南洛阳471003 湖南医药学院第一附属医院胸外科湖南怀化418000

目的探讨三孔单向式法与两孔法胸腔镜肺叶切除术加系统性淋巴结清扫治疗非小细胞肺癌(NSCLC)的特点。方法 2013年5月至2016年6月对我院120例确诊NSCLC的患者行胸腔镜肺叶切除+系统性肺门及纵隔淋巴结清除术。其中76例行三孔单向式胸腔... 详细信息

目的探讨三孔单向式法与两孔法胸腔镜肺叶切除术加系统性淋巴结清扫治疗非小细胞肺癌(NSCLC)的特点。方法 2013年5月至2016年6月对我院120例确诊NSCLC的患者行胸腔镜肺叶切除+系统性肺门及纵隔淋巴结清除术。其中76例行三孔单向式胸腔镜肺叶切除术,44例行两孔解剖性胸腔镜肺叶切除术。比较两组手术时间、术中出血量、清扫淋巴结个数、术后胸管留置时间和引流量、术后12 h疼痛(VAS评分)、术后并发症和生存率等指标。结果两组均无围手术期死亡发生。两组术中出血量、清扫淋巴结个数、术后胸管留置时间和引流量、术后并发症等比较均无统计学差异(均P>0.05)。三孔单向式手术时间(118.52±26.84)min,明显短于两孔法的(181.51±36.82)min(P<0.05)。术后12 h疼痛评分比较,三孔组VAS评分(3.2±0.7)分,明显高于两孔组的(2.5±0.4)分(P<0.05)。随访1~3 a,三孔单向式随访率88.16%(67/76),两孔法随访率84.09%(37/44)。三孔单向式7例,两孔法4例Ⅱb期患者因肿瘤复发或转移死亡。结论三孔单向式法胸腔镜肺叶切除相对于两孔法手术时间短、学习操作难度低,更适宜在基层医院开展。

关键词：电视胸腔镜手术非小细胞肺癌肺叶切除术