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China Communications 2024年第3期21卷 230-246页

作者： Tong Minglei Li Song Han Wanjiang wang xiaoxiang School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116China School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and TelecommunicationsBeijing 100876China

Mobile edge computing(MEC)-enabled satellite-terrestrial networks(STNs)can provide Internet of Things(IoT)devices with global computing ***,the network state information is uncertain or *** deal with this situation,we investigate online learning-based offloading decision and resource allocation in MEC-enabled STNs in this *** problem of minimizing the average sum task completion delay of all IoT devices over all time periods is *** decompose this optimization problem into a task offloading decision problem and a computing resource allocation problem.A joint optimization scheme of offloading decision and resource allocation is then proposed,which consists of a task offloading decision algorithm based on the devices cooperation aided upper confidence bound(UCB)algorithm and a computing resource allocation algorithm based on the Lagrange multiplier *** results validate that the proposed scheme performs better than other baseline schemes.

关键词： computing resource allocation mobile edge computing satellite-terrestrial networks task offloading decision

Enhancement in the Hg^(0) oxidation efficiency and sulfur resistance of CuCl_(2)-modified MnO_(x)-CeO_(x) nanorod catalysts

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 680-686页

作者： Shujie GAO Yongjin HU Zhichang JIANG xiaoxiang wang Dong YE Changxing HU College of Quality&Safety Engineering China Jiliang UniversityHangzhou 310018China Key Laboratory of Biomass Chemical Engineering of Ministry of Education Institute of Industrial Ecology and EnvironmentCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China School of Mechatronics and Energy Engineering Ningbo Tech UniversityNingbo 315100China

In this study,a series of CuCl_(2)-modified MnO_(x)-CeO_(x)nanorods were synthesized for the oxidation of Hg^(0).The addition of CuCl_(2)resulted in an enhancement in the catalyst’s Hg^(0)oxidation ability,and Hg^(0)oxidation efficiency reached>97%from 150 to 250°*** the MnO_(x)-CeO_(x)catalysts,Mn^(4+)played the role of the active species for Hg^(0)oxidization,but in the CuCl_(2)-doped catalysts Cl−also contributed to Hg^(0)oxidation,conferring the superior performance of these *** introduction of SO_(2) led to a decrease in the availability of Mn^(4+),and the Hg^(0)oxidation efficiency of MnO_(x)-CeO_(x)decreased from about 100%to about 78%.By contrast,CuCl_(2)-promoted samples maintained a Hg^(0)oxidation efficiency of about 100%during the SO_(2) deactivation cycle due to the high reactivity of Cl−.

关键词： Hg^(0)oxidation CuCl_(2)modification MnO_(x)-CeO_(x)nanorods Sulfur resistance O_(x)idation activity

Mechanistic investigation on the Hg^(0)elimination ability of MnO_(x)-CeO_(x)nanorod adsorbents:effects of Mn/Ce molar ratio

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Waste Disposal and Sustainable Energy 2024年第2期6卷 185-196页

作者： Shujie Gao xiaoxiang wang Yaolin wang Kai Zhu Changxing Hu Dong Ye College of Quality and Safety Engineering China Jiliang UniversityHangzhou 310018China Key Laboratory of Biomass Chemical Engineering of Ministry of Education Institute of Industrial Ecology and EnvironmentCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK Ningbo Tech University No.1 Qianhu South RoadNingbo 315100China

Mercury pollution is created by coal combustion processes in multi-component *** injection was identified as a potential strategy for capturing Hg^(0)from waste gases,with adsorbents serving as the primary *** hydro-thermal approach was used to synthesize a series of MnO_(x)-CeO_(x)nanorod adsorbents with varying Mn/Ce molar ratios to maximize the Hg^(0)capture *** CeO,had weak Hg elimination activity;<8%Hg^(0)removal efficiency was obtained from 150℃to 250℃.With the addition of MnOr,the amount of surface acid sites and the relative concentration of Mn4+*** ensured the sufficient adsorption and oxidation of Hg while overcoming the limitations of restricted adsorbate-adsorbent interactions caused by the lower surface area,endowing MnO_(x)-CeO_(x)with increased Hg^(0)removal *** the molar ratio of Mn/Ce reached 6/4,the adsorbent's Hg^(0)removal efficiency remained over 92%at 150℃and 200℃.As the molar ratio of Mn/Ce grew,the adsorbent's Hg^(0)elimination capacity declined due to decreased surface area,weakened acidity,and decreased activity of Mn^(4+);<75%Hg^(0)removal efficiency was reached between 150℃and 250℃for virgin *** the overall Hg'elimination reactions,Mn4+and *** in charge of oxidizing Hg^(0)to Hg^(0),with Ce^(4+)acting as a promoter to aid in the regeneration of Mn^(4+),Because of its limited adaptability to flue gas components,further optimization of the MnO_(x)-CeO_(x)nanorod adsorbent is required.

关键词： Hg^(0)capture MnO_(x)-CeO_(x)nanorods Mn/Ce molar ratio Acid properties Redox behaviors

Porous Indium Nanocrystals on Conductive Carbon Nanotube Networks for High-Performance CO2-to-Formate Electrocatalytic Conversion

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Energy & Environmental Materials 2024年第4期7卷 413-421页

作者： Liangping Xiao Rusen Zhou Tianqi Zhang xiaoxiang wang Renwu Zhou Patrick J.Cullen Kostya (Ken) Ostrikov Department of Physics Research Institute for Biomimetics and Soft Matter Fujian Provincial Key Laboratory for Soft Functional Materials Jiujiang Research Institute Xiamen University School of Chemistry and Physics QUT Centre for Materials Science and QUT Centre for a Waste-Free World Queensland University of Technology(QUT) School of Chemical and Biomolecular Engineering University of Sydney

Ever-increasing emissions of anthropogenic carbon dioxide （CO2） cause global environmental and climate *** by biological photosynthesis,developing effective strategies NeuNlto up-cycle CO2into high-value organics is *** CO2reduction reaction （CO2RR） is highly promising to convert CO2into economically viable carbon-based chemicals or fuels under mild process conditions.

关键词： CO2RR conductive network electrocatalysts formate

Spatial Distribution and Release Flux of Carbon and Nitrogen Components in Glacial Watersheds of Eastern Tibetan Plateau

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Journal of Earth Science 2024年

作者： Xiaoyu Jiao Zhiwen Dong Xiang Qin xiaoxiang wang Yaping Shao State Key Laboratory of Cryosphere Sciences， Northwest Institute of Eco-Environment and Resources， Chinese Academy of Sciences University of Chinese Academy of Sciences School of Geography and Information Engineering， China University of Geosciences Institute of Geophysics and Meteorology， University of Cologne

The carbon cycle stands as a cornerstone among the Earth's material cycles， carrying profound implications for global climate dynamics and humanity's sustenance and advancement. Additionally， nitrogen， as a vital nutrient element， plays a pivotal role in biogeochemical processes， exerting significant influence on the ecological environment within watersheds. In this study， an analysis of the carbon （C） and nitrogen （N） components in the river water of 12 alpine basins on the eastern margin of the Tibetan Plateau （TP） reveals that the average dissolved organic carbon （DOC） concentration in the river water is 0.76±0.67 mg/L， indicating a lower level compared to the global river average organic carbon content. Specifically， the average DOC concentrations were 0.42±0.22 mg/L and 1.56±0.68 mg/L in the glacial and non-glacial basins， respectively. The average dissolved inorganic carbon （DIC） concentration in the eastern TP is 27.04±20.19 mg/L， with the lowest DIC observed at Dagu Glacier and the highest at Daxia River. Furthermore， the average dissolved total carbon （DTC） concentration in glacier river water was 18.87±12.65 mg/L， contrasting with 48.23±21.07 mg/L in non-glacial basins. The mean concentration of total nitrogen （TN） in the eastern TP averaged 0.97±0.54 mg/L， with the glacial basin registering 1.01±0.47 mg/L and the non-glacial basin at 0.89±0.70 mg/L. Evaluating the release fluxes of carbon and nitrogen across 12 river basins revealed a range of DTC emission fluxes from 0.32 to 31.02 × 109g C/a， with inorganic carbon comprising 71.0% to 99.5%. Consequently， the carbon emission flux for seven glacier basins totaled 15.91 × 109g C/a， while for the five non-glacial river basins， it reached 87.37× 109g C/a. The total TN release fluxes across 12 small river basins amounted to 2.46 × 109g N/a， with 0.84 × 109g N/a released in glacial basins and 1.62 × 109g N/a in the non-glacial basin. This study elucidates the spatial distribution and transport mechanisms of car

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移动边缘计算使能的星地网络D2D辅助任务卸载

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北京邮电大学学报 2024年第1期47卷 25-30页

作者：佟明磊李松王晓湘北京邮电大学信息与通信工程学院北京100876 北京邮电大学泛网无线通信教育部重点实验室北京100876 中国矿业大学信息与控制工程学院徐州221116

针对地面设备计算资源未得到有效利用的问题,研究了移动边缘计算使能的星地网络中设备到设备(D2D)辅助任务卸载。建模了最大化所有用户设备、服务设备和低轨道地球卫星的效用的问题,并将其分解为任务卸载比例优化子问题和任务卸载决策... 详细信息

针对地面设备计算资源未得到有效利用的问题,研究了移动边缘计算使能的星地网络中设备到设备(D2D)辅助任务卸载。建模了最大化所有用户设备、服务设备和低轨道地球卫星的效用的问题,并将其分解为任务卸载比例优化子问题和任务卸载决策子问题。通过理论推导分别得到了D2D卸载和移动边缘计算卸载的最优任务卸载比例的解析解,并设计了一种基于匹配博弈的任务卸载决策算法,提出了一种任务卸载比例和任务卸载决策联合优化方案。仿真结果证明,与参考方案相比,所提方案具有更好的性能。

关键词：移动边缘计算星地网络设备到设备任务卸载

氧含量及晶粒尺寸对Ti-Zr二元合金拉伸屈服行为的影响

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材料科学与工程学报 2024年第1期42卷 21-26,83页

作者：梁林弘王宜平王小祥浙江大学材料科学与工程学院浙江杭州310027

对不同氧含量的温轧态Ti-Zr二元合金进行不同温度的退火及二次时效处理,发现氧含量与晶粒尺寸影响Ti-Zr合金表现出的拉伸屈服行为。通过拉伸试验、金相分析、透射电镜观察及应变时效和EDS元素分布研究了不同锆、氧含量钛合金的屈服延伸... 详细信息

对不同氧含量的温轧态Ti-Zr二元合金进行不同温度的退火及二次时效处理,发现氧含量与晶粒尺寸影响Ti-Zr合金表现出的拉伸屈服行为。通过拉伸试验、金相分析、透射电镜观察及应变时效和EDS元素分布研究了不同锆、氧含量钛合金的屈服延伸与微观组织的联系。研究结果表明:Ti-12Zr-0.25O合金在晶粒尺度处于1~15μm区间时,表现出典型的屈服延伸现象,随着晶粒尺寸增大,屈服延伸逐渐减弱;氧含量从0.1wt%增加至0.3wt%,Ti-12Zr合金表现出最大的上下屈服点应力差值及最大屈服点延伸率,分别为47MPa,5.2%;仅当锆、氧原子共同存在时,屈服延伸得到明显增强,以Ti-12Zr-0.25O尤甚。

关键词： Ti-Zr二元合金氧含量晶粒尺寸屈服行为锆氧“协同增强”

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高温后结构钢材单调拉伸和循环荷载试验研究

建筑钢结构进展 2024年第2期26卷 13-23页

作者：余玉洁张翔王霄翔中南大学高速铁路建造技术国家工程研究中心长沙410075 中南大学土木工程学院长沙410075 湖南建设投资集团有限责任公司长沙410004

现有的火灾后钢材残余特性研究大多着眼于钢材在高热下或升温后的残余静力特性,而对过火后钢材在循环荷载作用下的滞回和抗震特性鲜有研究。对于建筑结构和桥梁中常用的Q235和Q355两种钢材,对其进行了500~1000℃的模拟火灾加热处理,并... 详细信息

现有的火灾后钢材残余特性研究大多着眼于钢材在高热下或升温后的残余静力特性,而对过火后钢材在循环荷载作用下的滞回和抗震特性鲜有研究。对于建筑结构和桥梁中常用的Q235和Q355两种钢材,对其进行了500~1000℃的模拟火灾加热处理,并进行自然冷却或浸水冷却。对于冷却后的钢材试样进行了单向拉伸试验和2种不同荷载变化规律下的循环加载试验,得到了模拟温度和不同降温方式对于两种钢材滞回特征的影响规律。由试验结果可得,在受到的最高温度不高于600℃时,Q235和Q355钢材在自然冷却和浸水冷却后的单向拉伸和往复荷载工况下,其强度等级和弹塑性强度发展特征均与相应的未进行加热处理的钢材相似。当过火温度高于600℃时,自然冷却后Q235和Q355钢材的初始屈服强度会随过火极限温度的升高而逐渐下降。但在循环荷载影响下,钢材存在循环硬化效应,且该效应将随着过火极限温度的升高而逐渐显著。高温经历所导致的强度削弱会逐渐恢复。Q235和Q355钢材在循环荷载作用下的滞回刚度会逐渐下降,且极限温度和冷却方式会影响滞回刚度的下降幅度。高温过火且浸水冷却条件下,Q235和Q355钢材循环硬化效应显著,弹性域增长显著,循环荷载作用下塑性耗能能力下降明显。

关键词：结构钢材高温后冷却方式单调拉伸循环加载滞回性能

OXIDE FILM ON EQUIATOMIC TiNi SHAPE MEMORY ALLOY

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中国有色金属学会会刊：英文版 1998年第3期8卷 100-103页

作者： wang, xiaoxiang Zhejiang Univ Hangzhou China

１ＩＮＴＲＯＤＵＣＴＩＯＮＥｑｕｉａｔｏｍｉｃＴｉＮｉｓｈａｐｅｍｅｍｏｒｙａｌｏｙ（ＳＭＡ）ｉｓａｎｏｖｅｌａｎｄｐｒｏｍｉｓｉｎｇｂｉｏｍａｔｅｒｉａｌｄｕｅｔｏｉｔｓｕｎｉｑｕｅａｎｄｅｘｃｅｌｅｎｔｓｈａｐｅ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＥｑｕｉａｔｏｍｉｃＴｉＮｉｓｈａｐｅｍｅｍｏｒｙａｌｏｙ（ＳＭＡ）ｉｓａｎｏｖｅｌａｎｄｐｒｏｍｉｓｉｎｇｂｉｏｍａｔｅｒｉａｌｄｕｅｔｏｉｔｓｕｎｉｑｕｅａｎｄｅｘｃｅｌｅｎｔｓｈａｐｅｍｅｍｏｒｙｅｆｅｃｔａｎｄｓｕｐ...

关键词： TiNi shape memory alloy oxidation surface modification

腹腔镜保留十二指肠的胰头切除术的围手术期疗效研究

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中华外科杂志 2024年第7期62卷 671-676页

作者：尹韬远汪小祥张航郭兴军王敏秦仁义华中科技大学同济医学院附属同济医院胆胰外科武汉430030

目的比较腹腔镜保留十二指肠的胰头切除术(LDPPHR)与腹腔镜胰十二指肠切除术(LPD)治疗胰头交界性肿瘤及良性疾病的围手术期效果。方法本研究为回顾性队列研究。回顾性收集2020年1月至2022年12月华中科技大学同济医学院附属同济医院胆胰... 详细信息

目的比较腹腔镜保留十二指肠的胰头切除术(LDPPHR)与腹腔镜胰十二指肠切除术(LPD)治疗胰头交界性肿瘤及良性疾病的围手术期效果。方法本研究为回顾性队列研究。回顾性收集2020年1月至2022年12月华中科技大学同济医学院附属同济医院胆胰外科通过LDPPHR或LPD治疗的87例胰头交界性肿瘤及良性疾病患者的围手术期资料。男性49例, 女性38例, 年龄[M(IQR)]57.0(16.5)岁(范围:20~75岁)。其中40例接受LDPPHR, 47例接受LPD。正态分布的定量资料采用Student′st检验进行比较, 非正态分布的定量资料采用Mann-WhitneyU检验进行比较, 分类变量的比较采用χ^(2)检验或Fisher确切概率法。使用Logistic回归分析估计与并发症发生相关的危险因素。结果 LDPPHR组和LPD组患者的再手术率、总住院时间、术后住院时间、90 d病死率、30 d及90 d再入院率和2年肿瘤复发率的差异均无统计学意义(P值均>0.05)。LDPPHR组的围手术期并发症发生率高于LPD组[80.0%(32/40)比51.1%(24/47);χ^(2)=7.89, P=0.005], 但两组Clavien-Dindo并发症分级系统≥Ⅲ级并发症发生率的差异无统计学意义[10.0%(4/40)比12.8%(6/47);χ^(2)0.05)。单因素Logistic回归分析结果表明, LDPPHR(参照LPD, OR=3.83, 95%CI:1.46~10.04, Z=2.73, P=0.006)和术前胆管支架置入(参照不使用胆管支架, OR=5.30, 95%CI:1.13~25.00, Z=2.11, P=0.035)是总体并发症发生的危险因素, 但两者均不是总体并发症发生的独立危险因素(P值均>0.05)。结论初步研究结果显示, 在治疗胰头交界性及良性疾病方面, LDPPHR可获得与LPD相当的围手术期安全性和有效性。

关键词：胰腺肿瘤胰十二指肠切除术胰腺交界性肿瘤腹腔镜保留十二指肠的胰头切除术腹腔镜胰十二指肠切除术