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Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials

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Journal of Environmental Sciences 2025年第3期149卷 524-534页

作者： yue Liu Junjie Liu Ji Xiao jing Ye Lixu Guo Caiqing Yan Center for Environmental Metrology National Institute of Metrology ChinaBeijing 100029China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Environment Research Institute Shandong UniversityQingdao 266237China

Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate *** measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source *** accurate separation of OC and EC is controversial due to the charring of ***,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further *** RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC *** develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz *** generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC *** RMs were analyzed using different *** homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol ***,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.

关键词： Carbonaceous aerosol Split point Reference material Laboratory-generated Traceability

Response surface optimization of preparation parameters and evaluation of the antioxidant and antihypertensive activities of Spirulina protein hydrolysates

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Journal of Oceanology and Limnology 2025年第1期43卷 196-209页

作者： Qishan SUO Zhenzhen DENG Yang yue jing WANG Ning WU Lihua GENG Quanbin ZHANG CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Qingdao Marine Science and Technology CenterQingdao 266237China University of Chinese Academy of Sciences Beijing 101408China

Safety,high protein content,and the numerous health benefits make Spirulina an outstanding source of bioactive *** from Spirulina,which exhibit antioxidant,anti-inflammatory,and antihypertensive effects,may assist in the management of cardiovascular diseases(CVDs).Here,we present the optimization of enzyme-digested hydrolysates derived from Spirulina *** using response surface methodology(RSM).We also evaluated the biological activity of Spirulina protein hydrolysates(SPHs)in contributing to the amelioration of hypertension and associated cardiovascular *** findings suggest that Spirulina protein extracts contain a complex proteinaceous composition with phycocyanin being the dominant protein,as evidenced by both SDS-PAGE and LC-MS/MS *** protease,protease K,andα-chymotrypsin exhibited a substantial hydrolytic effect on Spirulina protein,taking into account their degree of hydrolysis(DH),peptide yield,and molecular weight ***-factor experiments identified pH,temperature,and enzyme/substrate ratio as the key factors influencing ***,optimal hydrolysis conditions for the proteases were determined via RSM,leading to a considerable enhancement of the actual *** showed that SPHs have strong antioxidant activity against various free radicals,with a higher ability to scavenge hydroxyl ***,SPHs inhibited macrophage nitric oxide secretion and significantly inhibited angiotensin I-converting enzyme in vitro at 400μg/*** is worth noting that SPHs prepared with protease K exhibited a potent anti-hypertensive effect in *** findings indicate the potential usefulness of including dietary SPHs in preventing hypertension and associated *** research could be valuable in guiding the development of health-promoting foods within the Spirulina industry.

关键词： antioxidant activity antihypertensive effect angiotensin converting enzyme inhibition response surface methodology Spirulina

多小区多用户无线网络下行链路协同波束成形设计

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通信学报 2012年第7期33卷 191-198页

作者：解培中郑宝玉岳文静南京邮电大学宽带无线通信与传感网技术教育部重点实验室江苏南京210003

在频率复用的多小区多用户无线网络中,为了获得较好的和速率性能,研究了降低同频干扰的协同波束成形设计问题。博弈论分析结果表明,性能最优的协同波束成形矢量是自私和利他策略的线性组合。提出了一种最大化和速率的波束成形矢量迭代算... 详细信息

在频率复用的多小区多用户无线网络中,为了获得较好的和速率性能,研究了降低同频干扰的协同波束成形设计问题。博弈论分析结果表明,性能最优的协同波束成形矢量是自私和利他策略的线性组合。提出了一种最大化和速率的波束成形矢量迭代算法,给出了基于信道状态统计量的组合系数的估计方法。最后,仿真评估了波束成形算法的性能,表明了所提迭代算法的收敛性。

关键词：波束成形博弈论均衡

认知无线电网络中基于协作水平的协作门限与功率联合优化

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电子与信息学报 2011年第10期33卷 2322-2327页

作者：张纬良郑宝玉岳文静南京邮电大学信号处理与传输研究院南京210003

将协作传输技术用于认知无线电网络不仅增强了系统抗衰落能力,而且有效提高了频带利用率。但是,中继节点何时必须参与协助源节点传输信息是一个值得考虑的问题。该文提出一种基于协作水平的中继协作准则。首先给出协作水平的定义和表达... 详细信息

将协作传输技术用于认知无线电网络不仅增强了系统抗衰落能力,而且有效提高了频带利用率。但是,中继节点何时必须参与协助源节点传输信息是一个值得考虑的问题。该文提出一种基于协作水平的中继协作准则。首先给出协作水平的定义和表达式,并基于此式推导了系统平均带宽利用率和误符号率公式,然后由二者的折中得到关于协作门限和功率比的性能函数。为了使系统获得最优性能,文中采用粒子群优化算法联合优化协作门限和功率比。仿真结果表明,良好的源节点到目的节点的链路状态和尽量使用中继参与协作均有助于系统性能的最优化。

关键词：认知无线电网络协作门限功率分配粒子群优化算法

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认知无线电系统中联合优化资源分配算法

南京邮电大学学报（自然科学版） 2012年第2期32卷 7-12,18页

作者：王晶郑宝玉岳文静南京邮电大学信号处理与传输研究院江苏南京210003

在认知无线电系统中,次用户能够利用感知到的已授权频段进行通信,只要其传输过程对主用户通信引起的干扰处于主用户可以忍受的程度之内。协作中继方案能够利用中继节点的传输来有效提高频谱的利用率,并增强了直接链路的传输能力。文中... 详细信息

在认知无线电系统中,次用户能够利用感知到的已授权频段进行通信,只要其传输过程对主用户通信引起的干扰处于主用户可以忍受的程度之内。协作中继方案能够利用中继节点的传输来有效提高频谱的利用率,并增强了直接链路的传输能力。文中研究在一个三节点的认知无线电网络中基于协作中继传输时的资源分配问题,为了保证在认知用户对主用户干扰可容忍的前提下使得通信系统端到端的可达吞吐量最大,提出了一种联合优化功率分配和信道分配的方案。仿真结果显示,相对于单独进行功率分配或者信道分配情况下该方案能够有效提高认知无线电系统端到端的传输性能。

关键词：认知无线电网络协作中继功率控制频谱分配

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基于可靠次用户信息的协作频谱感知算法研究

电子与信息学报 2012年第5期34卷 1208-1213页

作者：岳文静陈志郑宝玉王磊南京邮电大学宽带无线通信与传感网技术教育部重点实验室南京210003 东南大学移动通信国家重点实验室南京210096

对认知无线电系统最基本要求之一就是次用户必须有能力以高的精确率来确定主用户是否存在。而以前对认知无线电频谱感知的研究表明:在实际认知网络中次用户之间的相互协作可以提高其频谱检测性能。然而,对于协作频谱感知而言,随着协作... 详细信息

对认知无线电系统最基本要求之一就是次用户必须有能力以高的精确率来确定主用户是否存在。而以前对认知无线电频谱感知的研究表明:在实际认知网络中次用户之间的相互协作可以提高其频谱检测性能。然而,对于协作频谱感知而言,随着协作次用户数目的增加,势必会增大用于传输本地检测结果到融合中心的专用控制信道带宽,从而增加系统开销。该文在控制信道带宽有限的约束条件下,提出一种通过考虑可靠次用户信息的协作频谱感知算法来进一步改善频谱检测的性能。该算法的基本思想:只有具有可靠的本地检测结果的次用户才发送自己的检测结果到融合中心,否则,该次用户不发送任何信息。同时,对提出的该算法在理论上进行了推导,通过仿真结果表明:在控制信道带宽受限的约束下,相比于传统的"或"门协作频谱感知算法,提出的算法能够大大改善对主用户的检测性能。

关键词：认知无线电动态频谱接入频谱感知能量检测

Attribution analysis of trends in reference crop evapotranspiration in China

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Journal of Geographical Sciences 2025年第1期35卷 3-16页

作者： LIU yue GUO Mengjing LI jing LYU Na ZHANG Junqi ZHANG Bowen State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an710000China

Reference crop evapotranspiration(ET_(0)) is essential for determining crop water requirements and developing irrigation *** this study,ET_(0) was calculated via the FAO-56 Penman-Monteith model,and the spatiotemporal variations in ET_(0) over China from 1960 to 2019 were *** then quantified the contributions of five driving factors(air temperature,wind speed,relative humidity,sunshine hours,and CO_(2) concentration)to the ET_(0) trends via a detrending *** results revealed that nationwide ET_(0) showed no significant(p>0.05)decreasing trend from 1960 to 2019,with a trend of−8.56×10^(−2)mm a^(−2).The average temperature and wind speed were identified as the dominant factors affecting ET_(0)trends at the national *** contributions of the driving factors to the ET_(0) trends were ranked in the following order:average temperature(21.3%)>wind speed(−15.63%)>sunshine hours(−11.99%)>CO_(2) concentration(6.36%)>relative humidity(3.58%).Spatially,the dominant factors influencing the ET_(0) trends varied *** the southeastern region,average temperature and sunshine hours dominated the trends of ET_(0),whereas wind speed and average temperature were the dominant factors in the northwestern *** findings provide valuable insights into the dominant factors affecting ET_(0)trends in China and highlight the importance of considering different driving factors in calculating crop water requirements.

关键词： reference crop evapotranspiration climate change contribution rate trend analysis

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基于压缩感知技术的双向中继信道估计

信号处理 2012年第1期28卷 33-38页

作者：袁文文郑宝玉岳文静南京邮电大学信号处理与传输研究院江苏南京210003

设计了一种基于压缩感知(compressive sensing,CS)技术的双向中继信道(two-way relay channels,TWRC)估计方法,并具体采用正交匹配追踪算法(orthogonal matching pursuit,OMP)对OFDM系统下的信道脉冲响应进行估计。双向中继信道往往呈... 详细信息

设计了一种基于压缩感知(compressive sensing,CS)技术的双向中继信道(two-way relay channels,TWRC)估计方法,并具体采用正交匹配追踪算法(orthogonal matching pursuit,OMP)对OFDM系统下的信道脉冲响应进行估计。双向中继信道往往呈现出稀疏多径结构,这种结构会随着信号空间维数的增大而越加明显。传统的线性估计方法没有考虑到TWRC的潜在稀疏性,因而导致了对关键通信资源的过度使用。而基于CS的TWRC估计方法能够很好地利用这种传输信道的稀疏多径结构,与传统线性估计方法相比,在获得同样估计性能的前提下,需要的训练序列长度大大减少,有效地提高了频谱、能量等资源利用率。同时,所采用的OMP算法的时间复杂度主要依赖于信道稀疏度,因此计算效率往往比传统的方法高。仿真也证实了基于CS的TWRC估计算法的优越性。

关键词：压缩感知双向中继信道正交匹配追踪稀疏多径结构训练序列

Characterization of petrophysical and seismic properties for CO2 storage with sensitivity analysis

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Petroleum Science 2025年第1期22卷 193-209页

作者： Yan-Jiao Dong Yi Shen Kai Guo Xiao-Qin Wu Qiang Mao wen-yue Sun Zhi-Qiang Wang State Key Laboratory of Offshore Oil and Gas Exploitation Geosciences Department China University of Petroleum (East China) CNOOC Research Institute Ltd. School of Petroleum Engineering China University of Petroleum (East China)

Saline aquifers are considered as highly favored reservoirs for CO2sequestration due to their favorable properties. Understanding the impact of saline aquifer properties on the migration and distribution of CO2plume is crucial. This study focuses on four key parameters—permeability, porosity, formation pressure, and temperature—to characterize the reservoir and analyse the petrophysical and elastic response of CO2. First, we performed reservoir simulations to simulate CO2saturation, using multiple sets of these four parameters to examine their significance on CO2saturation and the plume migration ***, the effect of these parameters on the elastic properties is tested using rock physics *** established a relationship of compressional wave velocity（Vp） and quality factor（Qp） with the four key parameters, and conducted a sensitivity analysis to test their sensitivity to Vpand Qp. Finally, we utilized visco-acoustic wave equation simulated time-lapse seismic data based on the computed Vpand Qpmodels, and analysed the impact of CO2saturation changes on seismic data. As for the above numerical simulations and analysis, we conducted sensitivity analysis using both homogeneous and heterogeneous models. Consistent results are found between homogeneous and heterogeneous models. The permeability is the most sensitive parameter to the CO2saturation, while porosity emerges as the primary factor affecting both Qpand Vp. Both Qpand Vpincrease with the porosity, which contradicts the observations in gas reservoirs. The seismic simulations highlight significant variations in the seismic response to different parameters. We provided analysis for these observations, which serves as a valuable reference for comprehensive CO2integrity analysis, time-lapse monitoring, injection planning and site selection.

关键词： CO2 storage Time-lapse seismic CO2 plume Sensitivity analysis Rock physics Reservoir simulation Saline aquifer