北部湾典型海岛生态系统服务价值空间异质性对比研究

基于北部湾海域典型海岛高分1号数据,借助于CART决策树方法,获取了广西北部湾两个典型海岛的景观格局数据,并采用生态系统服务价值计量模型、空间自相关模型及地统计学中的变异函数模型对其生态系统服务价值进行了空间异质性分析。结果表明:团和岛单位面积生态系统服务价值是七星岛的1.08倍,但其变异系数低于七星岛;七星岛由于其地质背景为泥沙岛,景观格局受到人类活动以及自然环境的强烈干扰,趋向于复杂化和破碎化;而团和岛由于所处的外部环境以及自身的地质特征,景观格局呈现出整体斑块化分布状态;团和岛的景观格局主要受到结构性因素的控制,而七星岛则以随机性因素控制为主,选用变程和Moran’s指数来表征其复杂化和破碎化,来决定其优先开发时序,可对前者进行适当开发,而对后者适当进行生态保护;对受到结构性因素影响的岛屿在进行开发时,时序的识别选用变程和Moran’s指数来表征,若变程和Moran’s指数越小,说明海岛整体的景观分布格局趋向于复杂化和破碎化,反之生态系统较好,可进行优先开发。同时本文构建了北部湾海岛生态系统异质性评估与自然资源管理框架,并提出了海岛管理的建议与对策。     

内蒙古扎鲁特地区鲁D2井林西组烃源岩 有机地球化学特征

烃源岩生烃潜力的定量评价是研究盆地油气勘探潜力的重要手段.采用有机质丰度、类型、成熟度和沉积环境指标定量或定性评价了鲁D2井暗色泥岩的生烃潜力.有机碳定量评价表明,林西组泥岩为中等有机质丰度烃源岩.依据Pr/nC17、Ph/nC18散点图揭示林西组有机质类型以Ⅱ1型为主;伽玛蜡烷指数指示有机质形成于半咸水、还原环境,有利于有机质的保存.伊利石结晶度分析表明,烃源岩演化进入过成熟阶段.结果表明,扎鲁特盆地林西组泥岩为中等丰度、Ⅱ型干酪根、过成熟烃源岩,具有良好的页岩气勘探前景.     

Three-dimensional analysis of ozone and PM<Subscript>2.5</Subscript> distributions obtained by observations of tethered balloon and unmanned aerial vehicle in Shanghai,China

A lightweight unmanned aerial vehicle (UAV) and a tethered balloon platform were jointly used to investigate three-dimensional distributions of ozone and PM_2.5 concentrations within the lower troposphere (1000 m) at a localized coastal area in Shanghai, China. Eight tethered balloon soundings and three UAV flights were conducted on May 25, 2016. Generalized additive models (GAMs) were used to quantitatively describe the relationships between air pollutants and other obtained parameters. Field observations showed that large variations were captured both in the vertical and horizontal distributions of ozone and PM_2.5 concentrations. Significant stratified layers of ozone and PM_2.5 concentrations as well as wind directions were observed throughout the day. Estimated bulk Richardson numbers indicate that the vertical mixing of air masses within the lower troposphere were heavily suppressed throughout the day, leading to much higher concentrations of ozone and PM_2.5 in the planetary boundary layer (PBL). The NO and NO₂ concentrations in the experimental field were much lower than that in the urban area of Shanghai and demonstrated totally different vertical distribution patterns from that of ozone and PM_2.5. This indicates that aged air masses of different sources were transported to the experimental field at different heights. Results derived from the GAMs showed that the aggregate impact of the selected variables for the vertical variations can explain 94.3% of the variance in ozone and 94.5% in PM_2.5. Air temperature, relative humidity and atmospheric pressure had the strongest effects on the variations of ozone and PM_2.5. As for the horizontal variations, the GAMs can explain 56.3% of the variance in ozone and 57.6% in PM_2.5. The strongest effect on ozone was related to air temperature, while PM_2.5 was related to relative humidity. The output of GAMs also implied that fine aerosol particles were in the stage of growth in the experimental field, which is different from ozone (aged air parcels of ozone). Geographical parameters influenced the horizontal variations of ozone and PM_2.5 concentrations by changing underlying surface types. The differences of thermodynamic properties between land and sea resulted in quick changes of PBL height, air temperature and dew point over the coastal area, which was linked to the extent of vertical mixing at different locations. The results of GAMs can be used to analyze the sources and formation mechanisms of ozone and PM_2.5 pollutions at a localized area.     

建筑结构监测与抗震韧性评估

建筑结构响应是有效反映结构动力特性的最直接参数,开展结构动力响应实时监测可为结构抗震韧性评估提供准确的地震动输入。本文基于非结构构件损失构建结构抗震韧性评估方法,研究确定位移敏感型和加速度敏感型非结构构件的易损性模型。选择某六层钢筋混凝土框架结构进行实时监测系统建设,基于监测数据开展结构抗震韧性评估。通过构建建筑信息模型（BIM）,并在有限元分析软件OpenSees中建立结构弹塑性分析模型,利用实时监测数据实现结构模型更新,直至监测数据与模型分析结果一致。由于实时监测数据峰值较低,结构不会发生塑性变形,因此选择10条双向非脉冲地震动模拟实时监测地震记录。根据层间位移角和楼面加速度分布,开展结构功能损失评估,得到该建筑结构的抗震韧性得分。分析表明,该结构抗震性能较好,在遭受地震破坏后,会发生非结构构件脱落,需要采取有效措施进一步提升建筑抗震韧性水平。     

Effects of a proline solution cover on the geochemical and mineralogical characteristics of high-sulfur coal gangue

Batch experiments were conducted to comparatively evaluate the inhibition effects and mechanisms of a low-concentration (1%) proline solution cover on the release of pollutants from high-sulfur coal gangue. High-sulfur coal gangue was continuously immersed in a proline solution and in deionized water (as a control treatment) for 540 days. The results showed that the coal gangue in the control treatment was oxidized and generated leachate with poor water qualities, i.e., the leachate exhibited lower pH values, higher redox potential values, higher pollutant concentrations (SO₄^2?, Fe, Mn, Cu, and Zn), and high levels of acidophilic sulfur-oxidizing bacteria. However, compared to the control treatment, the addition of the proline solution (1%) significantly improved the water quality of the leachate by significantly reducing the Eh values, the pollutant concentrations (SO₄^2?, Fe²⁺, Fe, Mn, Cu, and Zn), and the activity of acidophilic sulfur-oxidizing bacteria and by significantly increasing the pH value to neutral. The proline treatment significantly inhibited the oxidation of coal gangue and the release of pollutants, mainly by inhibiting the activity of acidophilic sulfur-oxidizing bacteria and by altering the heavy metal fractions and the mineralogical characteristics. Therefore, in engineering practice, workers should consider using an environmental friendly aqueous proline solution cover to achieve the in-situ control of pollutant releases from coal gangue dumps.     

2℃温升目标下中国排放配额分析

本文以国际社会当前所有主要分配方案为基础,研究了2℃温升目标下中国2011-2050年间排放配额,通过控制变量进一步分析了配额分配对于主要参数设置的敏感性。研究结果表明,在与2℃目标相兼容的RCP2.6路径下,到2050年中国CO₂累计排放配额范围为150～440 Gt CO₂,基于等人均排放的分配方式已经变得最不利于中国。为维护合理的排放权益,在气候谈判中中国必须坚持对历史排放的完整追溯。全球排放路径的设定对中国配额也有着非常显著的影响,当2050年全球配额比2010年排放减少40%～50%时,中国在2℃目标下CO₂累计配额范围为151～474 Gt CO₂,当减少50%～60%时为138～478 Gt CO₂,构成中国配额公平范围下限的方案受排放路径的影响更大。     

CP-MS测定饮用水中Fe的方法

通过实验确定了ICP-MS检测饮用水中Fe的质量质量浓度方法。检测方法的检出限(DL)和精密度(RSD)分别达到3.29ng/mL和4.49%(n=12)。     

Dynamic features of near-inertial oscillations in the Northwestern Pacific derived from mooring observations from 2015 to 2018

Near-inertial oscillation is an important physical process transferring surface wind energy into deep ocean.We investigated the near-inertial kinetic energy(NIKE) variability using acoustic Doppler current profiler measurements from a mooring array deployed in the tropical western Pacific Ocean along130°E at 8.5°N,11°N,12.6°N,15°N,and 17.5°N from September 2015 to January 2018.Spatial features,decay timescales,and significant seasonal variability of the observed NIKE were described.At the mooring sites of 17.5°N,15°N,and 12.6°N,the NIKE peaks occurred in boreal autumn and the NIKE troughs were observed in boreal spring.By contrast,the NIKE at 11°N and 8.5°N showed peaks in winter and troughs in summer.Tropical cyclones and strong wind events played an important role in the emergence of high-NIKE events and explained the seasonality and latitudinal characteristics of the observed NIKE.     

浅谈超声波透射法在灌注桩检测中的应用

目前国内外对于钻孔灌注桩水下混凝土质量检测的方法很多,如低应变反射波法、高应变动测法、单桩竖向静载抗压试验、钻芯法、超声波透射法等,每种检测方法都有它的适用范围和局限性。超声波透射法与其他检测法相比,该方法检测精度高,结果直观可靠,适合大直径桩、超长桩的基桩检测,故在钻孔灌注桩的完整性检测中,得到了广泛的运用,尤其在桥梁灌注桩中,超长、大直径桩几乎都采用了超声波透射法检测。本文对某工地大直径桩进行了超声波透射法检测,通过波形与照片对比,更好地验证了超声波透射法测试超长、大直径取得的效果。     

“75·8”持续性强降水事件及其大尺度水汽输送特征

首先研究了河南"75·8"强降水事件的极端异常特征,然后从水汽通量的角度定性分析这次事件的水汽输送特征,最后采用了Hysplit模型定量分析了不同源地的水汽来源对河南"75·8"强降水的贡献率。研究表明,1975年8月5-8日在河南省发生的是一次大范围持续性极端降水过程,事件发生期间区域平均降水程度超过其气候平均值3倍标准差。强降水事件是在中高纬度环流异常和台风共同作用下发生的,贝加尔湖以东阻塞高压和副热带高压合并阻挡了7503号台风北上。定量计算结果进一步表明,河南"75·8"强降水的水汽来源与7503号台风具有十分密切的联系。