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Integrated Intelligent Electromagnetic Radiator Design for Future THz Communication:A Review

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Chinese Journal of Electronics 2022年第3期31卷 499-515页

作者： lu xuyang Venkatesh Suresh Saeidi Hooman Sengupta Kaushik UM-SJTU Joint Institute Shanghai Jiao Tong University Electrical and Computer Engineering Princeton University

Advances in 6 G communication changes how machines and humans interact. The blossom of new applications demands significantly higher data bandwidth while preserving the mobility and sustainability of electronic wireless communication systems. It also demands an integrable system that allows convenient interactions between communication units and signal processing units.A review of CMOS-based THz communication system solutions is presented, with a focus on novel systematic EM-circuit co-design philosophy. This review starts with a review of THz power generation, followed by the discussion of THz localization and THz beamforming for efficient high-throughput communication.

关键词： submillimetre wave generation efficient high-throughput communication THz power generation THz localization integrable system integrated intelligent electromagnetic radiator design electronic wireless communication systems sustainability 6G communication communication system solutions future THz communication signal processing units mobility 6G mobile communication CMOS integrated circuits THz beamforming integrated circuit design array signal processing communication units CMOS systematic EM-circuit co-design philosophy

Modeling effects of temperature and precipitation on carbon characteristics and GHGs emissions in Abies fabric forest of subalpine

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Journal of Environmental Sciences 2008年第3期20卷 339-346页

作者： lu xuyang CHENG Genwei XIAO Feipeng FAN Jihui Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Abies fabric forest in the eastern slope of Gongga mountain is one type of subalpine dark coniferous forests of southwestern China. It is located on the southeastern edge of the Qinghai-Tibet plateau and is sensitive to climatic changes. A process-oriented biogeochemical model, Forest-DNDC, was applied to simulate the effects of climatic factors, temperature and precipitation changes on carbon characteristics, and greenhouse gases （GHGs） emissions in A. fabric forest. Validation indicated that the Forest-DNDC could be used to predict carbon characteristics and GHGs emissions with reasonable accuracy. The model simulated carbon fluxes, soil carbon dynamics, soil CO2, N2O, and NO emissions with the changes of temperature and precipitation conditions. The results showed that with variation in the baseline temperature from -2℃ to ＋2℃, the gross primary production （GPP） and soil organic carbon （SOC） increased, and the net primary production （NPP） and net ecosystem production （NEP） decreased because of higher respiration rate. With increasing baseline precipitation the GPP and NPP increased slightly, and the NEP and SOC showed decreasing trend. Soil CO2 emissions increased with the increase of temperature, and CO2 emissions changed little with increased baseline precipitation. With increased temperature and decreased baseline temperature, the total annual soil N2O emissions increased. With the variation of baseline temperature from -2℃ to ＋2℃, the total annual soil NO emissions increased. The total annual N2O and NO emissions showed increasing trends with the increase of precipitation. The biogeochemical simulation of the typical forest indicated that temperature changes strongly affected carbon fluxes, soil carbon dynamics, and soil GHGs emissions. The precipitation was not a principal factor affecting carbon fluxes, soil carbon dynamics, and soil CO2 emissions, but changes in precipitation could exert strong effect on soil N2O and NO emissions.

关键词： carbon characteristics greenhouse gases (GHGs) Forest-DNDC Abies fabric forest

Multi-path based secure communication in wireless mesh networks

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Journal of Systems Engineering and Electronics 2007年第4期18卷 818-824页

作者： Ding xuyang Fan Mingyu lu Xiaojun Zhu Dayong Wang Jiahao School of Computer Science and Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

Communication security is a critical aspect of QoS provisioning in wireless mesh network （WMN）. Because of the inherent characteristics of WMN, conventional security mechanisms cannot be applied. In order to guarantee the communication security, a novel communication security mechanism is proposed. The mechanism uses a communication encryption scheme to encrypt data packets and employs a risk avoidance scheme to avoid the malicious nodes during communications. Simulation results indicate that the mechanism is able to provide secure communication effectively and reduce the damage of attacks through multiple paths.

关键词： wireless mesh network secure communication key exchange risk avoidance

Formation and biocorrosion behavior of Zr-Al-Co-Nb bulk metallic glasses

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Chinese Science Bulletin 2012年第14期57卷 1723-1727页

作者： lu xuyang HUANG lu PANG ShuJie ZHANG Tao Key Laboratory of Aerospace Materials and Performance （Ministry of Education） School of Materials Science and Engineering BeihangUniversity Beijing 100191 China

Ni-and Cu-free Zr-Al-Co-Nb glassy alloys with different Nb and Co contents were synthesized by melt spinning and copper mold *** effects of Nb addition to partially replace Co in the Zr55Al20Co25 glassy alloy on the glass-forming ability,thermal properties,in-vitro biocorrosion behavior and surface wettability of the metallic glasses were *** addition of Nb up to 5 at.% slightly decreased the supercooled liquid region and the glass-forming ability(GFA),the alloys could be casted in a bulk glassy rod form with diameters up to *** Zr-Al-Co-Nb glassy alloys were spontaneously passivated with low passive current densities in phosphate buffered saline and Hanks' *** of "toxic" Co by Nb is effective in improved the corrosion resistance of the Zr-Al-Co glassy *** contact angle measurements showed that Nb addition increased the hydrophilicity of the glassy alloys,which may enhance cell adhesion of the alloys in biomedical applications.

关键词：大块金属玻璃腐蚀行为生物玻璃形成能力铌非晶合金锆铝

Dynamics of Above-and Below-ground Biomass and C,N,P Accumulation in the Alpine Steppe of Northern Tibet

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Journal of Mountain Science 2011年第6期8卷 838-844页

作者： lu xuyang YAN Yan FAN Jihui CAO Yingzi WANG Xiaodan Key Laboratory of Mountain Environment Evolvement and Regulation Institute of Mountain Hazards and Environment CAS Chengdu 610o41 China Shenzha Alpine Steppe and Wetland Ecosystem Observation and Experiment Station Institute of Mountain Hazards and Environment CAS Shenzha 85310o China

The temporal dynamics of the biomass, as well as the carbon （C）, nitrogen （N）, phosphorus （P） concentrations and accumulation contents, in above- and below-ground vegetation components were determined in the alpine steppe vegetation of Northern Tibet during the growing season of 2OLO. The highest levels of total biomass （311.68 g m-2）, total C （115.95 g m-2）, total N （2.60 g m-2）, and total P （0.90 g m-2） accumulation contents were obtained in August in 2010. Further, biomass and nutrient stocks in the below-ground components were higher than those of the above-ground components. The dominant species viz., Stipa purpurea and Carex moorcrofli had lower biomass and C, N, P accumulations than the companion species which including Oxytropis. spp., Artemisia capillaris Thunb., Aster tataricus L., and SO on.

关键词： Biomass Nutrient concentration Nutrient accumulation Alpine steppe Northern Tibet

Exploring plant adaptation strategies to phosphorus limitation induced by nitrogen addition:foliar phosphorus allocation and root functional traits analysis in two dominant subalpine tree species

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Journal of Plant Ecology 2024年第4期17卷 154-166页

作者： Yan Su Yongfeng Tang Yi Hu Meiyu Liu xuyang lu Baoli Duan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Sichuan Ecological Environment Construction Engineering Supervision Co. Ltd.Chengdu 610084China

Plants adapt to the limitation of soil phosphorus(P)induced by nitrogen(N)deposition through a complex interaction of various root and leaf functional *** this study,a pot experiment was conducted to explore the effects of different levels of N addition(control,low N[LN]:25 kg N ha^(-1) yr^(-1),high N[HN]:50 kg N ha^(-1) yr^(-1))on tree growth,leaf nutrient content,foliar P fractions and root characteristics of two dominant tree species,the pioneer species Salix rehderiana Schneid and the climax species Abies fabri(Mast.)Craib,in a subalpine forest in southwestern *** results demonstrated that LN addition had a minimal impact on leaf N and P ***,HN addition significantly decreased the leaf P content in both *** rehderiana exhibited more pronounced increases in specific root length and specific root area under P deficiency triggered by HN addition when compared with *** contrast,*** showed weaker morphological responses to N addition but had a higher proportion of foliar P to metabolic P,as well as higher root exudates rate and root phosphatase activity in response to HN *** fabri employs a synergistic approach by allocating a greater amount of leaf P to metabolite P and extracting P from the soil through P-mobilizing exudates and root phosphatase activity,while *** exhibits higher flexibility in modifying its root morphology in response to P limitation induced by HN *** study provides insights into subalpine tree species adaptation to N-induced P limitation,emphasizing its significance for guiding forest management and conservation in the context of global climate change.

关键词： N deposition root functional traits root morphology root exudation P-scavenging strategy

Simulating Carbon Sequestration and GHGs Emissions in Abies fabric Forest on the Gongga Mountains Using a Biogeochemical Process Model Forest-DNDC

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Journal of Mountain Science 2008年第3期5卷 249-256页

作者： lu xuyang CHENG Genwei XIAO Feipeng HUO Changfu Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The process-oriented model Forest-DNDC describing biogeochemical cycling of C and N and GHGs （greenhouse gases） fluxes （CO2, NO and N2O） in forest ecosystems was applied to simulate carbon sequestration and GHGs emissions in Abies fabric forest of the Gongga Mountains at southeastern edge of the Tibetan Plateau. The results indicated that the simulated gross primary production （GPP） of Abies fabric forest was strongly affected by temperature. The annual total GPP was 24,245.3 kg C ha^-1 yr^-1 for 2005 and 26,318.8 kg C ha^-1 yr^-1 for 2006, respectively. The annual total net primary production （NPP） was 5,935.5 and 4,882.2 kg C ha^-1 yr^-1 for 2005 and 2006, and the annual total net ecosystem production （NEP） was 4,815.4 and 3,512.8 kg C ha^-1 yr^-1 for 2005 and 2006, respectively. The simulated seasonal variation in CO2 emissions generally followed the seasonal variations in temperature and precipitation. The annual total CO2 emissions were 3,109.0 and 4,821.0 kg C ha^-1 yr^-1 for 2005 and 2006, the simulated annual total N2O emissions from forest soil were 1.47 and 1.36 kg N ha^-1 yr^-1 for 2005 and 2006, and the annual total NO emissions were 0.09 and o.12 kg N ha^-1 yr^-1 for 2005 and 2006, respectively.

关键词： Carbon sequestration Forest-DNDC GHGs Abiesfabric forest Gongga Mountains

Ni-Ti(-Zr)-P非晶合金的热稳定性及腐蚀行为

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稀有金属材料与工程 2013年第5期42卷 975-978页

作者：邱春龙黄璐卢旭阳廖琦逄淑杰张涛北京航空航天大学空天材料与服役教育部重点实验室北京100191

采用熔体旋淬法制备了Ni76Ti5P19和Ni73Ti5Zr3P19(at%)非晶合金,对其热稳定性及腐蚀行为进行了研究,并讨论了Zr元素的添加对Ni-Ti-P非晶合金性能的影响。结果表明,Zr元素的添加提高了Ni76Ti5P19非晶合金的玻璃转变温度(Tg)和晶化温度(T... 详细信息

采用熔体旋淬法制备了Ni76Ti5P19和Ni73Ti5Zr3P19(at%)非晶合金,对其热稳定性及腐蚀行为进行了研究,并讨论了Zr元素的添加对Ni-Ti-P非晶合金性能的影响。结果表明,Zr元素的添加提高了Ni76Ti5P19非晶合金的玻璃转变温度(Tg)和晶化温度(Tx),但使得过冷液体温度区间(ΔTx)有所降低。电化学实验表明,在NaCl、HCl和H2SO4溶液中,Ni-Ti(-Zr)-P非晶合金发生自钝化,具有良好的耐腐蚀性能,这可能归因于合金表面Ti/Zr和P元素的富集。在同一溶液中,与Ni76Ti5P19非晶合金相比,Ni73Ti5Zr3P19非晶合金具有较高的开路电位和较低的钝化电流密度。在Ni-Ti-P合金中添加元素Zr以替代部分Ni能够在钝化膜中引入ZrO2,从而提高合金表面氧化膜的保护性,改善合金的耐腐蚀能力。

关键词： Ni基合金 Zr 非晶合金热稳定性腐蚀行为

藏北高寒草地土壤有机质化学组成对土壤CO_2排放的影响

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草业科学 2019年第4期36卷 960-969,I0007页

作者：马书琴鲁旭阳河南师范大学旅游学院河南新乡453007 中国科学院水利部成都山地灾害与环境研究所山地表生过程与生态调控重点实验室四川成都610041

土壤有机质(Soil organic matter, SOM)是草地生态系统的重要碳库,但由于SOM形成的复杂性,长期以来对SOM化学组成特征的研究存在一定挑战性。本研究基于热裂解气相色谱–质谱联用(Pyrolysis-gas chromatography/mass spectrometry, Py-G... 详细信息

土壤有机质(Soil organic matter, SOM)是草地生态系统的重要碳库,但由于SOM形成的复杂性,长期以来对SOM化学组成特征的研究存在一定挑战性。本研究基于热裂解气相色谱–质谱联用(Pyrolysis-gas chromatography/mass spectrometry, Py-GC/MS)的方法,从SOM化学组成的角度分析了其对藏北高寒草甸和高寒草原两种高寒草地土壤CO_2排放的影响。研究结果显示:1)含氮化合物是两种高寒草地SOM化学组成中重要成分,分别占总SOM的38.0%和52.5%;2)多糖类和萜烯类在两种高寒草地SOM中差异性达到显著水平(P <0.05);3)通过分析两种草地SOM化学组成与土壤CO_2排放量之间的相关关系,发现多糖直接影响着土壤CO_2累积排放量,拟合方程为Y=86.76X+344.87(R^2=0.63, P<0.05),式中Y为CO_2累积排放量,X为多糖类的相对含量;4)SOM化学组成中多糖类、含氮化合物和芳香烃物质与土壤中细菌、真菌、放线菌、革兰氏阴性细菌和革兰氏阳性细菌之间显著相关(P <0.05)。综上可知,高寒草地SOM化学组成直接关系着土壤微生物的数量和CO_2的排放过程,SOM的化学成分和化学组成可以在一定程度上直接用于预测土壤CO_2的排放特征。

关键词：土壤有机质化学组成多糖木质素二氧化碳