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抽蓄进水球阀工作及检修密封的活动环密封设计选型

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水电站机电技术 2024年第5期47卷 75-77页

作者：施肖永杭州凯门机电设备有限公司浙江杭州310016

随着我国“十四五”规划和“碳达峰、碳中和”等战略目标的推进,风电、光伏等可再生能源得到了飞跃式发展,风能与太阳能为间歇性能源,发电量不稳定,需要储能设备来平稳电网,故大型储能设备—抽水蓄能电站,得以爆发式增长。承担抽水蓄能... 详细信息

随着我国“十四五”规划和“碳达峰、碳中和”等战略目标的推进,风电、光伏等可再生能源得到了飞跃式发展,风能与太阳能为间歇性能源,发电量不稳定,需要储能设备来平稳电网,故大型储能设备—抽水蓄能电站,得以爆发式增长。承担抽水蓄能电站安全保护措施的进水球阀,也备受市场的关注,进水球阀中的工作密封和检修密封上的活动环密封,是最易出现问题的部件,本文着重介绍了活动环密封在运行中出现的问题,以及相应的预防措施及改进方案,为进水球阀设计及制造等相关技术人员提供参考和借鉴。

关键词：活动环密封计算选型试验

西延高铁交叉并线区段GSM-R网络覆盖方案

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铁路技术创新 2024年第1期 73-81页

作者：马义安石小勇西成铁路客运专线陕西有限责任公司陕西西安710000 中铁第一勘察设计院集团有限公司通信信号设计院陕西西安710043

西延高铁与既有普速包西铁路、郑西高铁存在交叉并线区段,在2个区段均需进行GSM-R网络覆盖规划。首先根据西延高铁设计标准,确定西延高铁GSM-R无线子系统网络采用单网交织覆盖方式,主要从覆盖方式及电平要求、基站容量计算等方面开展论... 详细信息

西延高铁与既有普速包西铁路、郑西高铁存在交叉并线区段,在2个区段均需进行GSM-R网络覆盖规划。首先根据西延高铁设计标准,确定西延高铁GSM-R无线子系统网络采用单网交织覆盖方式,主要从覆盖方式及电平要求、基站容量计算等方面开展论证分析;从不同铁路列控等级出发,针对延安站交叉并线区段、郑西高铁交叉并线区段,制定相应的网络覆盖方案;对共小区基站开展实际测试,在设计速度350 km/h条件下,接收机天线输入端射频信号最小可用接收电平满足95%时间地点概率下,最小可用接收电平不小于-92 dBm的要求,可为类似复杂区段的GSM-R网络设计方案提供参考。

关键词：西延高铁 GSM-R 网络覆盖枢纽交叉并线高普共站

船模水动力噪声及孔腔激励载荷试验与计算对比分析

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振动与冲击 2024年第15期43卷 288-293,310页

作者：漆琼芳邓海华苗天丞谷雨施小勇汉江国家实验室武汉430064 武汉第二船舶设计研究所武汉430064 中国船舶科学研究中心江苏无锡214082

开展某远洋客船光体船模水下噪声测试及带孔腔船模的水动力激励载荷测试,并进行孔腔处稳态和瞬态流场计算,孔腔处脉动压力频谱计算曲线与试验曲线吻合较好。孔腔脉动压力线谱频率测试值与经验公式频率计算值对比良好,说明该公式在一定... 详细信息

开展某远洋客船光体船模水下噪声测试及带孔腔船模的水动力激励载荷测试,并进行孔腔处稳态和瞬态流场计算,孔腔处脉动压力频谱计算曲线与试验曲线吻合较好。孔腔脉动压力线谱频率测试值与经验公式频率计算值对比良好,说明该公式在一定情况下适用于船体条形格栅孔腔线谱频率的预估。采用统计能量法分析法计算光体船模中高频流激噪声,将流体激励以频率-波数功率谱的形式施加,可大大减少流场计算工作量,适合于工程快速预估。在工程一般范围内,阻尼损耗因子取值可导致噪声结果相差5.5 dB,说明阻尼损耗因子的取值会较大影响计算结果,有必要形成材料损耗因子随频率变化的数据库,为船舶噪声快速计算提供支撑。

关键词：船体模型频率波数谱孔腔线谱流激噪声统计能量分析法

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公共研发投入经济影响评估的国际实践与启示

全球科技经济瞭望 2024年第6期39卷 43-56页

作者：杜丹杨耀高白云施筱勇科技部科技评估中心北京100081

对公共研发投入的科技活动开展经济影响评估是发达国家政府普遍做法。选取了欧盟框架计划(Framework Programmes,FP)、人类基因组计划(Human Genome Project,HGP)、加拿大自然科学与工程理事会(Natural Sciences and Engineering Resear... 详细信息

对公共研发投入的科技活动开展经济影响评估是发达国家政府普遍做法。选取了欧盟框架计划(Framework Programmes,FP)、人类基因组计划(Human Genome Project,HGP)、加拿大自然科学与工程理事会(Natural Sciences and Engineering Research Council of Canada,NSERC)合作研发计划和美国国家标准与技术研究院(National Institute of Standards and Technology,NIST)研发项目的经济影响评估实践。具体分析了4个评估实践的经济影响评估逻辑框架、反事实分析、经济计量方法和选用指标。研究发现,完整的评估逻辑框架,科学的评估设计,成熟的经济计量模型和完备的指标数据等是经济影响评估的重要因素。通过国际评估实践分析与总结为中国国家科技计划影响评估提供经验借鉴。

关键词：经济影响评估评估逻辑框架经济计量方法评估指标国际经验

Distribution, residence time, autotrophic production, and heterotrophic removal of DOP in the Mirs Bay, northern South China Sea

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Acta Oceanologica Sinica 2019年第8期38卷 17-26页

作者： Huaming shi Yu Ma Xulu Li xiaoyong shi Junxiao Zhang College of Environmental Science and Engineering Ocean University of China Qingdao 266100 China South China Sea Marine Survey and Technology Center Ministry of Natural Resources Guangzhou 510300 China National Marine Hazard Mitigation Service Ministry of Natural Resources Beijing 100194 China

The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(TDOP) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the TDOP was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic.

关键词： dissolved organic phosphorus temporal and spatial distributions residence time autotrophic production heterotrophic removal Mirs Bay northern South China Sea

Nutrient Structure of the Taiwan Warm Current and Estimation of Vertical Nutrient Fluxes in Upwelling Areas in the East China Sea in Summer

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Journal of Ocean University of China 2014年第4期13卷 613-620页

作者： shi xiaoyong LI Hongmei WANG Hao College of Chemistry and Chemical Engineering Ministry of Education Ocean University of China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China National Marine Hazard Mitigation Service Fujian Marine Environment and Fishery Resource Monitoring Center

Based on field data for nutrients collected on the continental shelf of the East China Sea(ECS) during summer 2006, the structure and variations of nutrients in every water mass related to the Taiwan Warm Current(TWC) were analyzed. The supplementary effect of nutrient of upwelling on harmful algal blooms(HABs) in the ECS was also estimated, based on upwelling data. Then the maintenance contribution of nutrient of upwelling to HABs was assessed. The results showed that N/P ratio is fairly low in both surface and deep layers of the TWC, which possibly controls nutrient structure of the HABs-frequently-occuring areas. In upwelling areas, the rate of phosphate(PO4-P) uptake exceeds that of nitrate(NO3-N) of the TWC. The TWC may relieve PO4-P limitation during the process of HABs. Furthermore, upwelling plays an important role in providing nutrients to HABs. After estimating nutrient fluxes(NO3-N, PO4-P, Si O3-Si) in the upwelling areas along a typical section(S07), the results showed that the nutrient uptake rate is the greatest at 10-20 m below euphotic zone, sustaining the ongoing presence of HABs. The uptake rate of PO4-P is the highest among dissolved inorganic nutrients. Therefore, upwelling is most likely the main source of PO4-P supply to HABs.

关键词： nutrient structure flux Taiwan Warm Current upwelling East China Sea

The Burial of Biogenic Silica, Organic Carbon and Organic Nitrogen in the Sediments of the East China Sea

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Journal of Ocean University of China 2015年第3期14卷 464-470页

作者： WANG Lisha ZHANG Chuansong shi xiaoyong College of Chemistry and Chemical Engineering Ocean University of China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China National Marine Hazard Mitigation Service

We sampled the sediments of the East China Sea during 2005 and 2006, and analysed the contents of the biogenic matters: biogenic silica, organic carbon, and organic nitrogen. From the surface distribution we found the contents of these substances to be in the ranges of 0.72%-1.64%, 0.043%-0.82%, and 0.006%-0.11%, respectively. Their distributions were similar to each other, being high inside the Hangzhou Bay and low outside the bay. The vertical variations of the contents were also similar. In order to discuss the relation between them we analysed the variations of content with depth. They increased in the first 7 cm and then decreased with depth. The peaks were found at depths between 20 to 25 cm. The distribution of carbonate showed an opposite trend to that of biogenic matters. The content of total carbon was relatively stable with respect to depth, and the ratio of high organic carbon to carbonate showed a low burial efficiency of carbonate, which means that the main burial of carbon is organic carbon. In order to discuss the source of organic matters, the ratio of organic carbon to organic nitrogen was calculated, which was 8.01 to 9.65, indicating that the organic matter in the sediments was derived mainly from phytoplankton in the seawater.

关键词： burial sediment biogenic matters carbon and nitrogen ratio East China Sea

An estimation of nutrient fluxes to the East China Sea continental shelf from the Taiwan Strait and Kuroshio subsurface waters in summer

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Acta Oceanologica Sinica 2014年第11期33卷 1-10页

作者： LI Hongmei shi xiaoyong WANG Hao HAN Xiurong College of Chemistry and Chemical Engineering Ocean University of China National Marine Hazard Mitigation Service Fujian Marine Environment and Fishery Resource Monitoring Center

According to historical mean ocean current data through the field observations of the Taiwan Ocean Research Institute during 1991–2005 and survey data of nutrients on the continental shelf of the East China Sea（ECS） in the summer of 2006, nutrient fluxes from the Taiwan Strait and Kuroshio subsurface waters are estimated using a grid interpolation method, which both are the sources of the Taiwan Warm Current. The nutrient fluxes of the two water masses are also compared. The results show that phosphate（PO4-P）, silicate（SiO3-Si） and nitrate（NO3-N） fluxes to the ECS continental shelf from the Kuroshio upwelling water are slightly higher than those from the Taiwan Strait water in the summer of 2006. In contrast, owing to its lower velocity, the nutrient flux density（i.e., nutrient fluxes divided by the area of the specific section） of the Kuroshio subsurface water is lower than that of the Taiwan Strait water. In addition, the Taiwan Warm Current deep water, which is mainly constituted by the Kuroshio subsurface water, might directly reach the areas of high-frequency harmful alga blooms in the ECS.

关键词： nutrient flux Taiwan Warm Current summer East China Sea

Investigation of seasonal variability of CDOM fluorescence in the southern Changjiang River Estuary by EEM-PARAFAC

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Acta Oceanologica Sinica 2015年第10期34卷 1-12页

作者： BAI Ying SU Rongguo HAN Xiurong ZHANG Chuansong shi xiaoyong Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of China

The southern Changjiang River Estuary has attracted considerable attention from marine scientists because it is a highly biologically active area and is biogeochemically significant. Moreover, land-ocean interactions strongly impact the estuary, and harmful algal blooms （HABs） frequently occur in the area. In October 2010 and May 2011, water samples of chromophoric dissolved organic matter （CDOM） were collected from the southern Changjiang River Estuary. Parallel factor analysis （PARAFAC） was used to assess the samples＇ CDOM composition using excitation-emission matrix （EEM） spectroscopy. Four components were identified： three were humic-like （C1, C2 and C3） and one was protein-like （C4）. Analysis based on spatial and seasonal distributions, as well as relationships with salinity, Chl a and apparent oxygen utilization （AOU）, revealed that terrestrial inputs had the most significant effect on the three humic-like Components C1, C2 and C3 in autumn. In spring, microbial processes and phytoplankton blooms were also important factors that impacted the three components. The protein-like Component C4 had autochthonous and allochthonous origins and likely represented a biologically labile component. CDOM in the southern Changjiang River Estuary was mostly affected by terrestrial inputs. Microbial processes and phytoplankton blooms were also important sources of CDOM, especially in spring. The fluorescence intensities of the four components were significantly higher in spring than in autumn. On average, C1, C2, C3, C4 and the total fluorescence intensity （TFI） in the surface, middle and bottom layers increased by 123%-242%, 105%-195%, 167%-665%, 483%-567% and 184%-245% in spring than in autumn, respectively. This finding corresponded with a Chl a concentration that was 16-20 times higher in spring than in autumn and an AOU that was two to four times lower in spring than in autumn. The humification index （HIX） was lower in spring that in autumn, and the fluorescence index （F

关键词： southern Changjiang River Estuary chromophoric dissolved organic matter fluorescence excitationemission matrix spectroscopy parallel factor analysis humification index fluorescence index