The influence of solar ultraviolet radiation on the photochemical production of H2O2 in the equatorial Atlantic Ocean

Hydrogen peroxide (H₂O₂) was measured in marine surface waters of the eastern Atlantic Ocean between 25°N and 25°S. H₂O₂ concentrations decreased from 80 nM in the north to 20 nM in the south, in agreement with earlier observations. A diel cycle of H₂O₂ production as a function of sunlight in surface waters was followed twice whilst the ship steamed southward. Around 23°N a distinct diel cycle could be measured which correlated well with irradiance conditions.The wavelength dependency of H₂O₂ formation was studied near the equator. For 16 hours, water samples were incubated with wavelength bands of the solar spectrum, i.e. visible (VIS: 400–700 nm), VIS and ultraviolet A radiation (UVAR: 320–400 nm) and VIS, UVAR and ultraviolet B radiation (UVBR: 280–320 nm). A significant relationship was found between wavelength band and the production of H₂O₂. In addition, a clear positive relationship between intensity and production was found. UVAR was 6.5 times more efficient than VIS in producing 1 nM of H₂O₂, whereas UVBR was 228 times more efficient than VIS. When these data were weighted with respect to the energy of the solar spectrum at zenith hour, 28% of the H₂O₂ was formed by VIS, 23% was formed by UVAR and 48% was formed by UVBR. Considering the strong attenuation of UVBR in marine waters as compared with UVAR and VIS radiation, the role of UVAR deeper in the water column is recognised. Furthermore results of this research emphasise the importance of VIS radiation in the formation of H₂O₂.     

Focused fluid flow and the sub-seabed storage of CO2: Evaluating the leakage potential of seismic chimney structures for the Sleipner CO2 storage operation

The integrity of the caprock of a storage formation is the most crucial parameter for the long-term performance of a geological CO₂ storage site. The Sleipner area in the Southern Viking Graben hosts the first and longest operating industrial scale CO₂ storage project, where CO₂ is injected in a saline aquifer of the Utsira Formation. Time-lapse seismic monitoring shows neither that CO₂ has left the Utsira Formation nor indications for fracturing of the caprock by the CO₂ injection activity, which is in agreement with previous numerical simulations. However, large chimney structures as close as 7 km from the injection point indicate that the caprock has been breached in the geological past, which may raise questions about the integrity of the caprock above the Sleipner CO₂ storage site. Here, we present seismically constrained numerical fluid flow simulations that evaluate the influence of chimney structures on the long-term performance of the CO₂ storage operation at Sleipner. The simulation could reproduce the spreading of the Sleipner CO₂ plume, which is controlled by the anisotropic permeability field of the Utsira Formation and the regional dip of the formation top. We have performed long-term plume evolution simulations, which show that the injected CO₂ will not reach the existing chimney structures assuming a realistic injection duration of 30 years. Our simulations indicate that an unrealistically long injection period between 92 and 140 years would be required for the CO₂ to reach the existing chimney structures. In this case, a comparably low chimney permeability of 10 mD may be sufficient to facilitate CO₂ migration from the storage formation to the seafloor, once the CO₂ has reached a chimney structure. However, the simulations indicate that it is very unlikely that the CO₂ may migrate along existing chimney structures at Sleipner. Our results highlight that the reconstruction of palaeo fluid flow systems and the identification of focused fluid conduits should be considered in the assessment of CO₂ storage sites.     

The IKFS-2 Infrared Fourier-Transform Spectrometer Operating Onboard the Meteor-M No.2 Satellite

Izvestiya, Atmospheric and Oceanic Physics - The results of the commissioning of the IKFS-2 instrument and its subsequent operation onboard the Meteor-M no. 2 polar orbiting meteorological...     

基于反转法的O2 -CO2 输运性质预测

采用反转法计算得到了O₂-CO₂混合气体新的势能参数.在此基础上,根据分子动力学理论,计算了混合气体在零密度下的输运性质,包括黏度系数、热扩散系数和热扩散因子,计算的温度范围为273.15—3273.15 K.与实验值比较表明,计算结果可以满足实际工程应用.     

Thermodynamics of the system H2ONaClMgCl2Na2SO4MgSO4 at 25°C

Osmotic coefficients and Gibbs energies of mixing for the system H₂ONaClMgCl₂MgSO₄ have been calculated from isopiestic vapor pressure measurements. These results have been combined with earlier results from the system H₂ONaClNa₂SO₄MgSO₄ to construct Jänecke diagrams giving osmotic coefficients at constant ionic strength. Osmotic coefficients calculated from the theory of Reilly and Wood are in good agreement with measured values for the four-salt system, for compositions and ionic strengths comparable to those of natural brines.     

TiO2/Cu2O复合光催化剂的制备及表征

通过浸渍-还原法;在不同Cu2+/Ti4+摩尔比下制备TiO2/Cu2O复合光催化剂,通过X射线衍射(XRD)、扫描电镜(SEM)、紫外可见漫反射(UV-DRS)等手段对TiO2/Cu2O复合光催化剂进行了表征.在可见光照射下,研究TiO2/Cu2O复合光催化剂对水中难降解有机污染物甲基橙的光催化降解效果.结果表明,氙灯照射下,TiO2/Cu2O复合光催化剂与单纯的纳米TiO2 (P25)相比,光催化降解效果得到明显的提高.Cu2+/Ti4+摩尔比1∶2时制备的TiO/Cu2O复合光催化剂具有最好的光催化降解效果.     

On the CO2O2 system in the Northeastern Pacific

The TCO₂, O₂, TA and δ¹³C data of the 1969 Geosecs Intercalibration Cruise was analyzed and found to be consistent with a vertical mixing model which assumes that each point along a vertical profile is a mixture of the upper and lower boundaries. Calculated regression coefficients are in agreement with the model of Redfield et al. (1963) and with the assumption that TA variation is due to carbonate reaction. Oxygen consumption and TCO₂ production decrease exponentially with depth and approximately 80% of ΔCO₂ can be accounted for, on average, by O₂ consumption. The remaining 20% are probably due to carbonate solution which seems to take place at depths below 2,500 m. The present study suggests that the isotopic composition (δ¹³C) of the carbon source, required to account for most of the oxygen consumed, may be heavier than the value of −23%. assigned to dissolved organic carbon and particulate organic carbon.     

卤代噻唑胺基类化合物TSC-2c的抗肿瘤活性机制研究

三阴性乳腺癌是一种具有高度转移性,侵袭性的乳腺癌亚型,是女性易患且预后较差的肿瘤之一。本课题组修饰合成的噻唑胺基类杂化物TSC-2c具有对MDA-MB-231细胞独特的敏感性,细胞半数抑制率达到了4.45mM,且对正常细胞无毒副作用。本文中采取细胞划痕、Transwell小室、克隆形成、流式细胞术等方法,研究了该化合物对MDA-MB-231细胞迁移、侵袭、克隆斑形成及细胞凋亡的影响。结果表明,TSC-2c通过增加细胞凋亡比例,显著影响了MDA-MB-231细胞的增殖、迁移和侵袭能力,对三阴性乳腺癌的药物研发及治疗具有重要理论意义。     

The validation of the significant wave height product of HY-2 altimeter-primary results

The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height （SWH） is validated by the data from the South China Sea （SCS） field experiment, National Data Buoy Center （NDBC/ buoys and Jason-1/2 altimeters, and is corrected using a linear regression with in-situ measurements. Com- pared with NDBC SWH, the HY-2 SWH show a RMS of 0.36 m, which is similar to Jason- 1 and Jason-2 SWH with the RMS of 0.35 m and 0.37 m respectively; the RMS of corrected HY-2 SWH is 0.27 m, similar to 0.27 m and 0.23 m of corrected Jason-1 and Jason-2 SWH. Therefore the accuracy of HY-2 SWH products is close to that of Jason-1/2 SWH, and the linear regression function derived can improve the accuracy of HY-2 SWH products.     

Effects of vehicle,diet and gender on the expression of PMP70- and CYP2K1/2M1-like proteins in the mummichog

The mummichog (Fundulus heteroclitus) has been shown to be responsive to peroxisome proliferating agents (PPAs). Peroxisomes function as important sites for fatty acid beta-oxidation. Peroxisome proliferation by PPAs or starvation can lead to changes in the size and number of peroxisomes and the expression of omega-hydroxylases (CYP2K1/2M1 in rainbow trout). Mummichogs were subjected to 96 h fasting or 96 h recovery from fasting. Expression of PMP70- and CYP2K1/2M1-like proteins in vehicle-treated or non-treated controls was compared in both males and females. Fasting and vehicle produced decreases in PMP70- and CYP2K1/2M1-like proteins in both males and females. In reproductive females, decreases due to fasting and vehicle treatment were greater than in female fish that were not gravid. Recovery from fasting resulted in levels of CYP2K1/2M1 near control levels in males while in recovered females, about 2-fold higher levels compared to controls were noted. These results indicate that gender, reproductive status and diet can produce changes in the expressed levels of peroxisomal PMP70 and microsomal CYP2K1/2M1-like proteins in the mummichog.     

New estimates of Southern Ocean biological production rates from O2/Ar ratios and the triple isotope composition of O2

We report O₂/Ar ratios (a constraint on net community production) and the triple isotopic composition of dissolved O₂ (a constraint on gross primary production) in samples collected from the surface mixed layer on 23 Southern Ocean transits. Samples were collected at 1–2° meridional resolution during the austral summer. Methodological limitations notwithstanding, the results constrain the net/gross production ratio, net O₂ production, and gross O₂ production at unprecedented resolution throughout the Southern Ocean mixed layer. Gross O₂ production rates inferred from the oxygen triple isotopes are greater than production rates calculated from a model based on remotely sensed chlorophyll. This result agrees with previous ¹⁸O and ¹⁴C incubations along 170°W. O₂/Ar ratios exceeding saturation are consistently observed within the Subantarctic and Polar Frontal Zones south of New Zealand and Australia, showing that a net autotrophic community predominates during austral summer. Lower O₂/Ar values are observed within the Drake Passage and Antarctic Zone, suggesting unresolved influences of low net community production, net heterotrophy, and upwelling of O₂-undersaturated waters. In autotrophic waters of the austral summer mixed layer, ratios of net community production/gross O₂ production scatter about 0.13, corresponding to f ratios of ∼0.25. Net community/gross O₂ production ratios show no meridional gradient across the Antarctic Circumpolar Current, suggesting that an approximately constant fraction of gross primary productivity is regenerated or exported. Our calculated net O₂ production rates are in satisfactory agreement with comparable published estimates. Net and gross O₂ production rates are highest in the Subantarctic and decline to the south, paralleling the well-known trend of chlorophyll a concentrations. In an analysis of variance of net O₂ production and gross O₂ production with other environmental variables, the strongest correlations are between net O₂ production and sea surface temperature (SST) (direct correlation), climatological [NO₃⁻] (inverse correlation), and estimates of primary productivity derived from a remote sensing (direct correlation). These trends are as expected if aerosol iron input is the most important influence on production. They are unexpected if upwelling-derived SiO₂ and iron are the leading influence or if lower SSTs promote greater export in this region.     

Feasibility of dumping fossil-fuel CO2 into the deep ocean

An idea has been proposed to recover and dispose of the fossil-fuel CO₂ generated by stationary power plants into the deep sea, thereby reducing the CO₂ emission to the atmosphere. The assessment of its environmental effects and risks is essential for developing new technology for the recovery/disposal system, which has recently received growing attention in Japan.The simple calculation made here did not yield any decisively significant environmental risks so far. However, a further detailed study is needed for the consequences of lowering local pH and the abrupt dissolution of CaCO₃ in the deep-sea sediments. It is also shown that, on longer term, the atmospheric concentration of CO₂ may be influenced by the degree at which the reaction between the disposed fossil-fuel CO₂ and the sedimentary CaCO₃ takes place under such conditions. At any rate, the problem should be brought to serious scientific attention much like the case of ocean dumping of radioactive wastes.     

Low CO2 concentrations in the Gulf of Guinea during the upwelling season in 2006

The fugacity of CO₂ (fCO₂) was measured underway from 27 May to 5 July 2006 in the Gulf of Guinea when the upwelling conditions were taking place. The equatorial and the coastal upwellings are responsible for the large CO₂ outgassing observed in the tropical Atlantic. The highest fCO₂ (655 μatm) was measured in the eastern coastal upwelling. However, area of low fCO₂ are also observed. Those occurred north of 2°N, in the Guinea Current, and near 6°S close to the coast due to the Congo River discharge. The decrease of salinity is a major factor explaining low fCO₂. In the South Equatorial Counter Current region, south of 6°S near 10°W, low fCO₂ are not related to a salinity effect as this region is subject to excess evaporation. A comparison with the meridional transects of the RMS St Helena made in 1995–1996 near 15°W suggests that these low fCO₂ or even slight undersaturations can be observed from about 4°S to 10°S. It seems that they occur mainly in boreal summer. They could be caused by transport of water that has been in contact with the atmosphere long enough to come close to equilibrium. The low fCO₂ area are not reproduced by the CO₂ climatology probably because of the coarse resolution and the lack of data in this region. Despite the low fCO₂ area observed in 2006, the ΔfCO₂ in 2006 is higher than the 1995 climatology for the region 10°S–2°N, 10°W–10°E suggesting that fCO₂ is increasing over time but from the few cruises available, it is difficult to definitely conclude.     

Accurate measurement of O2, N2, and Ar gases in water and the solubility of N2

The degree of atmospheric saturation for O₂, Ar, and N₂ gases in water can be determined to accuracies of ±0.1–0.3% using mass spectrometry to determine the gas ratios and Winkler titrations for oxygen analysis. We describe methods used to obtain this level of accuracy and precision. Oxygen accuracy of ±0.1% can be obtained by careful attention to standardization using KIO₃ standards that have been corrected for impurities. Accurate O₂/Ar and O₂/N₂ gas ratios (±0.1–0.2%) are obtainable by measuring the mass ratios against the atmosphere if the effect of different gas concentrations on the performance of the mass spectrometer are taken into account. Oxygen and argon saturation values have been determined previously to accuracies of less than or equal to ±0.1%, but published estimates of the saturation value for nitrogen differ by more than 1%. We have redetermined the N₂ saturation value at 19°C and zero salinity to be 0.92% greater than the results reported in the work of Weiss (1970).     

HY-2A卫星海面高度数据质量评估

对HY-2A卫星雷达高度计数据进行筛选获取有效的观测点,利用HY-2A卫星第18~23周期数据和同时在轨的Jason-2数据进行交叉点选取,对两颗卫星在交叉点海面高度异常值的差值进行统计与分析,提出了基于交叉点差值统计特征的筛除HY-2A轨道数据方法,评估了HY-2A卫星雷达高度数据质量。结果显示,HY-2A卫星18~23周期阈值筛选去除的点个数占总海洋观测点约12%,HY-2A海面高度异常与Jason-2海面高度异常的标准偏差在7.0 cm,数据精度满足设计精度要求。     

HY-2B卫星散射计海面风场产品质量分析 *

星载微波散射计是获取全球海面风场信息的主要手段, HY-2B卫星散射计的成功发射为全球海面风场数据获取的持续性提供了重要保障。本文利用欧洲中期天气预报中心(European Center for Medium-Range Weather Forecasts, ECMWF)再分析风场数据、热带大气海洋观测计划(Tropical Atmosphere Ocean Array, TAO)和美国国家数据浮标中心(National Data Buoy Center, NDBC)浮标获取的海面风矢量实测数据, 对HY-2B散射计海面风场数据产品的质量进行统计分析。分析表明, HY-2B风场与ECMWF再分析风场对比, 在4~24m·s^-1风速区间内, 风速和风向均方根误差(root mean square error, RMSE)分别为1.58m·s^-1和15.34°; 与位于开阔海域的TAO浮标数据对比, 风速、风向RMSE分别为1.03m·s^-1和14.98°, 可见HY-2B风场能较好地满足业务化应用的精度要求(风速优于2m·s^-1, 风向优于20°)。与主要位于近海海域的NDBC浮标对比, HY-2B风场的风速、风向RMSE分别为1.60m·s^-1和19.14°, 说明HY-2B散射计同时具备了对近海海域风场的良好观测能力。本文还发现HY-2B风场质量会随风速、地面交轨位置等变化, 为用户更好地使用HY-2B风场产品提供参考。     

台湾海峡M_2分潮的三维数值模拟

本文利用普林斯顿海洋模式对台湾海峡 Ｍ ２ 分潮作了分辨率较高的三维数值模拟。在较准确地模拟了潮汐分布的基础上,研究了 Ｍ ２ 分潮流椭圆分析、最大流同时线分布、潮流场的水平及垂直结构,最后还给出了 Ｍ ２ 分潮余流、余水位的分布。结果表明, Ｍ ２ 分潮最大流同时线在海峡中部同时形成密集区和一个圆流点;构成海峡潮波系统的两股潮波中,南支潮波的影响似超出了以往所认为的范围;最大潮流仅在近海底处急剧减小,最大流方向随深度增加右转,到近底层又向左转;潮汐余流和余水位均较弱,仅在澎湖水道、台湾浅滩附近余流较大。     

南黄海夏季表层海水中pCO2分布的初步探讨

作者在 1 999年夏季的航次中 ,获得了南黄海表层海水 p CO2 的实测数据。本文结合水文、化学和生物等要素的同步观测资料 ,对影响 p CO2 分布和变化的某些重要现象进行了初步探讨。研究表明南黄海表层海水 p CO2 的分布存在较大的不均匀性 ,这是边缘海区海水中生物、物理和化学因素复合作用的结果。除长江口门外的 p CO2 高值区外 ,南黄海表层海水的 p CO2 值与叶绿素、水温大体呈负相关 ,而与海水的盐度基本上呈正相关。     

2008年夏季加拿大海盆净二氧化碳吸收量评估

The third Chinese National Arctic Research Expedition(CHINARE) was conducted in the summer of 2008.During the survey,the surface seawater partial pressure of CO_2(pCO_2) was measured,and sea water samples were collected for CO_2 measurement in the Canada Basin.The distribution of pCO_2 in the Canada Basin was determined,the influencing factors were addressed,and the air-sea CO_2 flux in the Canada Basin was evaluated.The Canada Basin was divided into three regions:the ice-free zone(south of 77°N),the partially ice-covered zone(77°–80°N),and the heavily ice-covered zone(north of 80°N).In the ice-free zone,pCO_2 was high(320 to 368μatm,1 μatm=0.101 325 Pa),primarily due to rapid equilibration with atmospheric CO_2 over a short time.In the partially ice-covered zone,the surface pCO_2 was relatively low(250 to 270 μatm) due to ice-edge blooms and icemelt water dilution.In the heavily ice-covered zone,the seawater pCO_2 varied between 270 and 300 μatm due to biological CO_2 removal,the transportation of low pCO_2 water northward,and heavy ice cover.The surface seawater pCO_2 during the survey was undersaturated with respect to the atmosphere in the Canada Basin,and it was a net sink for atmospheric CO_2.The summertime net CO_2 uptake of the ice-free zone,the partially ice-covered zone and the heavily ice-covered zone was(4.14±1.08),(1.79±0.19),and(0.57±0.03) Tg/a(calculated by carbon,1Tg=10~(12) g),respectively.Overall,the net CO_2 sink of the Canada Basin in the summer of 2008 was(6.5±1.3) Tg/a,which accounted for 4%–10% of the Arctic Ocean CO_2 sink.     

Fishery provisions of the ICNT: Part 2

In the second of two articles analysing the fishery provisions of the ICNT/Rev 2, the author concentrates on unresolved legal problems of the world's marine fisheries. Difficulties associated with MSY and OSY, TAC, surplus, coastal state control over the EEZ, high-seas fishing, anadromous species, land-locked and geographically disadvantaged states, and sedentary species are discussed, and an assessment is made of the ICNT's attempt to ensure a more equitable distribution of world fishery resources.