千川汇海阔,风好正扬帆

以仰望星空的理想和抱负,以脚踏实地的务实和担当,以对党、对时代的感恩,以对责任与使命的思考,开创国家能源系统团青工作新局面……作为一名企业团干部,要始终把巩固和扩大党执政的青年群众基础作为政治责任,党旗所指就是团旗所向,牢记青春使命,积极助力青年成长成才,使团员有根、青年有力、工作有效,让朝气蓬勃的青年群体引领企业整体文化氛围.

Numerical Study of a Novel Procedure for Installing the Tower and Rotor Nacelle Assembly of Offshore Wind Turbines Based on the Inverted Pendulum Principle

Current installation costs of offshore wind turbines(OWTs) are high and profit margins in the offshore wind energy sector are low, it is thus necessary to develop installation methods that are more efficient and practical. This paper presents a numerical study(based on a global response analysis of marine operations) of a novel procedure for installing the tower and Rotor Nacelle Assemblies(RNAs) on bottom-fixed foundations of OWTs. The installation procedure is based on the inverted pendulum principle. A cargo barge is used to transport the OWT assembly in a horizontal position to the site, and a medium-size Heavy Lift Vessel(HLV) is then employed to lift and up-end the OWT assembly using a special upending frame. The main advantage of this novel procedure is that the need for a huge HLV(in terms of lifting height and capacity) is eliminated. This novel method requires that the cargo barge is in the leeward side of the HLV(which can be positioned with the best heading) during the entire installation. This is to benefit from shielding effects of the HLV on the motions of the cargo barge, so the foundations need to be installed with a specific heading based on wave direction statistics of the site and a typical installation season. Following a systematic approach based on numerical simulations of actual operations, potential critical installation activities, corresponding critical events, and limiting(response) parameters are identified. In addition, operational limits for some of the limiting parameters are established in terms of allowable limits of sea states. Following a preliminary assessment of these operational limits, the duration of the entire operation, the equipment used, and weather-and water depth-sensitivity, this novel procedure is demonstrated to be viable.

The impacts of modeling global CO2 concentrations with GEOS-Chem using different ocean carbon fluxes

The rise in atmospheric carbon dioxide(C02)concentrations caused by human activities is leading to global climate change,which poses a threat to human development and survival.This study analyzed the distribution of the ocean carbon flux with interannual changes and compared it with the climatological ocean carbon flux to deepen our understanding of carbon sources and sinks.To simulate global CO2 concentrations for the years2008-2010,the ocean carbon flux with interannual changes and the climatological ocean carbon flux were used to drive the GEOS-Chem model,an atmospheric chemical transport model.The simulated values were compared with the CO2 concentrations at nine observation stations to explore the influence of interannual changes in the ocean carbon fluxes on the simulated CO2 concentrations.The authors found that the difference between the two simulation results was greater in the Southern Hemisphere all year,and the difference in autumn was the largest.Compared with the observations,the simulated CO2 concentration of the ocean carbon flux with interannual changes is closer to the observations,indicating that this simulation is more accurate.

中文学科奋进中的回望与探寻——有感于《浙江大学中文系系史》出版

一初见三卷本《浙江大学中文系系史》,眼睛为之一亮,钦佩之情油然而生。我不得不深深佩服吴秀明教授等浙大中文系同仁的胆识。有胆,才敢为,因为同行都知道,要写百年老系史,诚非易事,非一般人所能为,且不说历史的远去、资料的散佚带来的搜集之难,仅人事的协调就颇令人费神;有识,才能为,因为要汇百年于一编,如何删繁就简、披沙拣金,着实需要大智慧。而摆在面前的这套书,仅以三卷文字,不只清晰地再现了浙大中文系众川汇海似的发展史,而且还为老师立传。

A Hybrid Approach for Studying the Lead-Lag Relationships Between China’s Onshore and Offshore Exchange Rates Considering the Impact of Extreme Events

Understanding the characteristics of the dynamic relationship between the onshore Ren- minbi （CNY） and the offshore Renminbi （CNH） exchange rates considering the impact of some extreme events is very important and it has wide implications in several areas such as hedging. For better esti- mating the dynamic relationship between CNY and CNH, the Granger-causality test and Bry-Boschan Business Cycle Dating Algorithm were employed in this paper. Due to the intrinsic complexity of the lead-lag relationships between CNY and CNH, the empirical mode decomposition （EMD） algorithm is used to decompose those time series data into several intrinsic mode function （IMF） components and a residual sequence, from high to low frequency. Based on the frequencies, the IMFs and a residual sequence are combined into three components, identified as short-term composition caused by some market activities, medium-term composition caused by some extreme events and the long-term trend.The empirical results indicate that when it only matters the short-term market activities, CNH always leads CNY; while the medium-term impact caused by those extreme events may alternate the lead-lag relationships between CNY and CNH.

The Heat Island Effect Response to the Urban Landscape Pattern of Haikou based on the“Source-Sink”Theory

The Landsat images of the 2000,2005,2010,2015,2018 are selected as the data source to retrieve land cover and surface temperature data.The contribution of Sink-Source landscape pattern to the heat island and its ecological effects on urban and rural gradient were analyzed by using Heat Index(HI),Sink and Source Landscape Contribution(CI_(sink),CI_(source))and Landscape Effect Index(LI)in Haikou.The results show that the heat island is concentrated on the West Coast,and in the central urban and Jiangdong New Area;the HI shows a pattern of decreasing value with the following land types:“Bare land>Artificial surface﹥Source landscape>Shrub grassland>Farmland>Sink landscape>Woodland>Water body”.In the central city section,the CI_(sink) and CI_(source) are relatively large in these five periods.The LI decreases rapidly along the urban-rural gradient,promoting the Urban Heat Island(UHI)to a large degree.In contrast,the suburban area contributes to a lesser degree.Overall,the LI fluctuates,the proportion of mitigating UHI is large,and there is a second peak outside the city center.The existing Source-Sink Landscape contributes the most to UHI in the central urban area,and this contribution decreases along the urban-rural gradient.With the continuous expansion of city-town areas,the proportion of Sink areas has increased along the gradient,and the proportion of Source areas has subsequently declined,resulting in the spatial transfer and diffusion of UHI.Therefore,a UHI mitigation strategy based on the theory of regional landscape systems is proposed here.

Hybridization chain reaction triggered controllable one-dimensional assembly of gold nanoparticles

Assembling and ordering nanomaterials into desirable patterns are considerably significant,since the properties of nanomaterials depend not only on the size and shape,but also on the spatial arrangement among the collective building blocks.In this work,the DNA self-assembly technology of hybridization chain reaction(HCR) provided a convenient method to yield long double-strand DNA(dsDNA) to install gold nanoparticles(AuNPs) into one dimensional assembly along the skeleton of dsDNA.Interestingly,the tunable length of AuNPs assemblies along dsDNA chain could be achieved by adjusting the reaction time of HCR,which is based on the formation of covalent bond between Au and the-SH group of DNA.Compared with weak light scattering of single AuNP,these AuNPs assemblies could be clearly imaged under the dark field microscopy,indicating that the light scattering was greatly improved after assembling.