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1.
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. 相似文献
2.
The Hawaii-2 Observatory 总被引：2，自引：0，他引：2
Petitt R.A. Jr. Harris D.W. Wooding B. Bailey J. Jolly J. Hobart E. Chave A.D. Duennebier F. Butler R. Bowen A. Yoerger D. 《Oceanic Engineering, IEEE Journal of》2002,27(2):245-253
A permanent deep ocean scientific research facility-the Hawaii-2 Observatory (H2O)-was installed on the retired HAW-2 commercial submarine telephone cable in September 1998. H2O consists of a seafloor submarine cable termination and junction box in 5000 m of water located halfway between Hawaii and California. The H2O infrastructure was installed from a large research vessel using the Jason ROV and standard over-the-side gear. The junction box provides two-way digital communication at variable data rates of up to 80 kbit/s using the RS-422 protocol and a total of 400 W of power for both junction box systems and user equipment. Instruments may be connected by an ROV to the junction box at 8 wet-mateable connectors. The H2O junction box is a "smart" design, which incorporates redundancy to protect against failure and allows full control of instrument functionality from shore. Initial instrumentation at the H2O site includes broad-band seismometer and hydrophone packages 相似文献
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海水中Ca2, Mg2的含量及Mg2/Ca2对日本鳗鲡受精卵孵化率的影响 总被引：3，自引：0，他引：3
日本鳗鲡 Ａｎｇｕｉｌｌａｊａｐｏｎｉｃａ)为降海洄游产卵鱼类 ,它生于江河等淡水水域,性成熟后要洄游到海洋中产卵 ,幼体在海洋中发育变态成柳叶鳗随海水漂游到河口近岸,并逐渐变态为白鳗苗进入江河生长［３］。虽然王义强等１９８０年就对鳗鲡的人工繁殖有过报道 ,但到目前,日本鳗鲡人工繁殖尚未成功［１ ,５］在日本鳗鲡人工繁殖过程中 ,常用近海区的海水作为实验用水。谢刚等１９９５年对日本鳗鲡幼体发育所需海水的温度、盐度作了报道。但近海区由于受河流淡水的影响,不仅盐度会有变化 ,而且海水中一些主要离子含量也很不恒定,从而… 相似文献
4.
研究了条纹小环藻（Cyclotella striata）对Cu2＋和Zn2＋的耐受力、吸附率和吸附量的作用规律.结果表明：Cu2＋和Zn2＋对条纹小环藻的生长影响显著（p〈0.05）,随着Cu2＋、Zn2＋含量的升高,其对条纹小环藻生长的抑制作用增大;当Cu2＋和Zn2＋的含量分别高于4.00×10-3、0.01 mg/dm3时,其对条纹小环藻的生长几乎没有影响;Cu2＋和Zn2＋对条纹小环藻生长的半抑制含量分别为0.26、11.17 mg/dm3.Cu2＋含量为1.00 mg/dm3和Zn2＋含量为50.00 mg/dm3的组合,对条纹小环藻生长的抑制率达72.28%,Cu2＋对条纹小环藻的毒性大于Zn2＋.条纹小环藻对Cu2＋、Zn2＋吸附效果良好,当藻细胞含量为2.45×107cells/dm3时,对Cu2＋的吸附率为63.00%;当藻细胞含量为1.75×107cells/dm3时,对Zn2＋的吸附率为60.52%;条纹小环藻对Cu2＋和Zn2＋的吸附量分别为9.26 mg/g（21.30×10-9mg/cell）和20.06 mg/g（46.15×10-9mg/cell）时,Cu2＋和Zn2＋对条纹小环藻不会产生明显毒性. 相似文献
5.
Vertical gas profiles of N2, N2O and O2were obtained in intact sediment cores from a Tagus estuary salt marsh using membrane inlet mass spectrometry. This technique allows direct measurements of dissolved gas concentrations with minimal disturbance. O2concentrations decreased sharply with depth, becoming undetectable below 14mm. Denitrification products (N2and N2O) occurred in the surface layer of the sediment where O2was present. Diffusion of N2and N2O from the anaerobic zone, denitrification in anaerobic microsites and aerobic denitrification are possible explanations for this observation. N2was the sole product of denitrification in control sediment cores probably because of the great demand for electron acceptors in this sediment. The addition of NO3 − and CH3CO2 − increased the concentrations of N2and N2O in the sediment. Significantly higher concentrations in treated cores occurred between 1·5 and 2·0cm for N2and between 0·5 and 1·5cm for N2O. The peak in N2concentration occurred in the anaerobic zone of the sediment, close to the aerobic–anaerobic interface while the peak in N2O concentration occurred above this interface where concentrations of O2were approximately 10μM. This is indicative that, in this sediment, production of N2O is less sensitive to the presence of O2than reduction of N2O to N2. 相似文献
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AbstractHY-2A, which was launched on 16 August 2011, is the Chinese first microwave ocean dynamics environment satellite. Analyses of HY-2A daily sea-level anomaly data and HY-2A–Jason-2 (H-J) dual crossover sea-level anomaly differences show that HY-2A has measurement differences that mainly refer to an orbit error. H-J crossover differences and HY-2A–HY-2A (H-H) crossover differences give an estimate of the HY-2A orbit error. Smoothing cubic-spline functions are then used to obtain a continuous estimation of the HY-2A orbit error over time. On the basis of the simultaneous global minimization of H-J dual crossover differences and H-H crossover differences, the HY-2A observation error is efficiently reduced and height measurement data that are more precise are obtained. Specifically, the range bias/trend of the HY-2A altimeter is removed effectively and the root mean square of H-J crossover sea-level anomaly differences decrease from above 60?cm to 5.64?cm, and the standard deviation of H-J crossover differences decreases from 6.68 to 5.64?cm. Furthermore, the rms and standard deviations of H-H crossover differences both decrease from 7.46 to 6.55?cm. The results show that HY-2A after correction has a measurement accuracy and precision that are comparable to those of Jason-2. 相似文献
8.
Atmospheric CO_2 is one of key parameters to estimate air-sea CO_2 flux. The Orbiting Carbon Observatory-2(OCO-2) satellite has observed the column-averaged dry-air mole fractions of global atmospheric carbon dioxide(XCO_2)since 2014. In this study, the OCO-2 XCO_2 products were compared between in-situ data from the Total Carbon Column Network(TCCON) and Global Monitoring Division(GMD), and modeling data from CarbonTracker2019 over global ocean and land. Results showed that the OCO-2 XCO_2 data are consistent with the TCCON and GMD in situ XCO_2 data, with mean absolute biases of 0.25×10-6 and 0.67×10-6, respectively. Moreover, the OCO-2 XCO_2 data are also consistent with the CarbonTracker2019 modeling XCO_2 data, with mean absolute biases of 0.78×10-6 over ocean and 1.02×10-6 over land. The results indicated the high accuracy of the OCO-2 XCO_2 product over global ocean which could be applied to estimate the air-sea CO_2 flux. 相似文献
9.
在实验生态条件下研究了重金属离子(Cu2 、Pb2 、Hg2 、Cd2 )对日本鳃丝和肝胰脏显微结构(15d)的影响。观察结果表明:在2 mg/L Cu2 处理组,日本鳃叶不规则增厚,鳃腔相对扩大,其中血细胞明显增多;上皮层出现破坏:角质膜(CU)呈波状拱起,部分上皮细胞脱离角质膜形成大的空泡(VA);上皮细胞排列不规则,并与数目众多的血细胞充挤于血腔;肝胰脏中构成肝管的细胞发生严重崩解,只残留包被在外周的一层结缔组织的被膜。10mg/L Pb2 处理组鳃丝角质膜明显呈波状突起;肝管结构紊乱,开始出现大量空泡(VA)。0.1 mg/L Hg2 暴露下,鳃丝上皮层偶有溶解现象;肝胰脏肝细胞空泡化(VA)现象更为严重,细胞间界限不明显,肝细胞溶解,有些细胞核固缩;被膜中的结缔组织充血,出现血细胞浸润现象。1 mg/L Cd2 暴露下,鳃丝上皮层严重解体,只剩一层角质层,鳃腔相对扩大,部分区域有充血现象;肝胰脏出现细胞质溶解,细胞间界限不明显,血细胞浸润等现象。 相似文献
10.
采用溶胶凝胶法在不锈钢基体(304ss)上制备叠层式纳米SnO2/TiO2复合薄膜。使用X射线衍射(XRD)、扫描电子显微镜(SEM)表征纳米复合薄膜材料的晶体结构和微观形貌,通过交流阻抗技术(EIS)和极化曲线(Polarization Curves)电化学方法研究不锈钢表面纳米复合薄膜在模拟海水体系中的腐蚀行为。结果表明:制备叠层式纳米复合薄膜TiO2为锐钛矿型,SnO2为金红石型;不锈钢表面构筑叠层式纳米SnO2/TiO2复合薄膜颗粒粒径小,分布均匀且表面致密。电化学测试表明,叠层式纳米SnO2/TiO2复合薄膜阻抗值高于TiO2薄膜,且对不锈钢基体阳极反应有明显钝化过程,具有良好防腐蚀性能;同时叠层式纳米SnO2/TiO2复合薄膜存在最优叠加SnO2层数,叠加3层SnO2的纳米SnO2/TiO2复合薄膜电极防腐蚀性能最佳。 相似文献
11.
During N2-O2 simulated saturation at a depih of 36.5 m the frequency, amplitude and index of a waves decreased and the activities of β and θ wave increased on the EEGs at rest. After the pressure was decompressed to normal, they could recover to the predive level. During the air excursion diving at depths of 60 and 70 m , the paramenters of EEG approximated to those of N2-O2 exposure. But at that time of the air excursion diving at a depth of 75 m they appeared the maximum. This showed that the changes related to the nitrogen partial pressure. There was an increase in slow waves during the simulated N2-O2 saturation. The activities of slow wave decreased on the EEGs in case of hyperventilation. The photic scimulation to the eyes caused the slow wave to disappear, and a rhythm could recover temporarily. When the photic stimulation was over the slow rhythm reappeared on the EEG. All the changes in EEG indicated that the encephalon function of the human body showed a gradual adaptation process during the 相似文献
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R.F. Platford 《Marine Chemistry》1975,3(4):261-270
Osmotic coefficients and Gibbs energies of mixing for the system H2ONaClMgCl2MgSO4 have been calculated from isopiestic vapor pressure measurements. These results have been combined with earlier results from the system H2ONaClNa2SO4MgSO4 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. 相似文献
14.
Association constants of orthophosphate ion with Na+, Ca2+, and Mg2+ were measured at μ = 0.68 and 20°C. The results were used to calculate phosphate speciation in seawater. Free HPO42? ion and MgHPO4o are found to be the predominant species. 相似文献
15.
德国GSS-2型海洋重力仪更新性改造 总被引：3，自引：0，他引：3
本文简述了我国引进的德国海洋重力仪器现状，介绍了一种新研制成功的与GSS－2型海洋重力仪探头适配的数字检测控制装置和具当代先进水平的计算机虚拟仪表终端系统，并给出了GSS－2型海洋重力仪更新性改造后的测量应用结果。 相似文献
16.
泛素结合酶(UbcE2)是蛋白泛素化过程中所必需的酶,在泛素转移和底物的特异性识别方面发挥着重要的作用。本实验利用RACE技术克隆获得了全长为993bp的松江鲈泛素结合酶E2-D2基因cDNA序列(命名为TfUbcE2-D2),其开放阅读框为444bp,编码147个氨基酸。通过SMART预测得知,TfUbcE2-D2含有一个UBCc结构域。同源比对结果表明该基因与其他物种的同源性为92.31%。实时荧光定量PCR显示,TfUbcE2-D2广泛表达于松江鲈各组织,在肾脏中的相对表达量最高,其次为鳃。鳗弧菌(Vibrio anguillarum)刺激后,TfUbcE2-D2在血液、脾脏、肝脏和鳃中表达均上调,其中,脾脏和鳃中的表达量上调约40倍。由以上实验结果推测,TfUbcE2-D2可能参与松江鲈的先天免疫防御。 相似文献
17.
Polyakov A. V. Timofeyev Yu. M. Uspensky A. B. Kukharsky A. V. 《Izvestiya Atmospheric and Oceanic Physics》2018,54(9):1391-1398
Izvestiya, Atmospheric and Oceanic Physics - The validation of measurements of vertical temperature profiles by the IKFS-2 instrument (the Meteor-M no. 2 satellite) in cloudless conditions was... 相似文献
18.
《Journal of Sea Research》2004,51(1):3-10
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. 相似文献
19.
SARAL/AltiKa GDR-T are analyzed to assess the quality of the significant wave height (SWH) measurements. SARAL along-track SWH plots reveal cases of erroneous data, more or less isolated, not detected by the quality flags. The anomalies are often correlated with strong attenuation of the Ka-band backscatter coefficient, sensitive to clouds and rain. A quality test based on the 1 Hz standard deviation is proposed to detect such anomalies. From buoy comparison, it is shown that SARAL SWH is more accurate than Jason-2, particularly at low SWH, and globally does not require any correction. Results are better with open ocean than with coastal buoys. The scatter and the number of outliers are much larger for coastal buoys. SARAL is then compared with Jason-2 and Cryosat-2. The altimeter data are extracted from the global altimeter SWH Ifremer data base, including specific corrections to calibrate the various altimeters. The comparison confirms the high quality of SARAL SWH. The 1 Hz standard deviation is much less than for Jason-2 and Cryosat-2, particularly at low SWH. Furthermore, results show that the corrections applied to Jason-2 and to Cryosat-2, in the data base, are efficient, improving the global agreement between the three altimeters. 相似文献
20.
用小麦岛和团岛观测站提供的青岛近海气象和水温资料,以适于SO2气体和硫酸盐(SO42-)气溶胶的干沉降模型研究了模型中的输送阻尼对两种污染物质干沉降速率的贡献,并计算了2003年青岛近海地区两种污染物质干沉降速率的季节变化。结果表明:对SO2而言,粘性副层传输系数对沉降速率的贡献大于空气动力学传输系数;对于SO42-,空气动力学传输系数对沉降速率的贡献要大于表面传输系数。SO2和SO42-的干沉降速率变化范围分别为0.187~0.868cm/s和0.188~0.532cm/s。两种污染物质干沉降速率的四季变化有相似的规律,即冬季>秋季>春季>夏季。 相似文献