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211.
东海表层沉积物碎屑矿物组合分布特征及其物源环境指示 总被引:1,自引:1,他引:0
为进一步明确东海陆架区的沉积物物源及水动力环境,对研究区表层沉积物的碎屑矿物进行了鉴定分析。研究区共鉴定出49种重矿物、8种轻矿物。根据碎屑矿物的组合分布结合矿物形态特征,将东海陆架区划分为三个矿物区,内陆架矿物区、外陆架矿物区及虎皮礁矿物区。内陆架矿物区,动力分选是影响碎屑矿物分布的主要因素,物质来源相对单一,碎屑矿物主要来源于现代长江物质,闽浙沿岸近岸河流的输入,人类活动也对该区的矿物组成产生一定的影响;外陆架矿物区,重矿物分布的主控因素是长期的分选作用,主要是长江物质经后期改造形成,现代长江物质可从内陆架中北部扩散至124.5°E左右,此外外陆架东南部地形的变化也对碎屑矿物的分布起到一定控制作用;虎皮礁矿物区,有来自黄河、长江、火山物质的多重影响,且水动力环境相对复杂。 相似文献
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213.
Chuanbo Zhou Shiwei Lu Nan Jiang Dingbang Zhang Zhihua Zhang Gaojian Miao 《Geotechnical and Geological Engineering》2016,34(3):847-866
In Daye Iron Mine, the open-pit mining has ended and the underground mining started in 2003. The present pit slopes are as high as 430 m and the slope angle is up to 43°. During the process of open-pit to underground mining, the high-steep pit slopes would be affected by both open-pit mining and underground mining, and its deformation characteristics would become more complex. So in this paper, the trinity method of numerical simulation, model experiment and field test was adopted to analyze the displacement and stress fields systematically. The results show that: (1) Prominent rebound deformation occurs near the slope foot, which is induced by the unloading in open-pit mining. When it is backfilled to 0 m level, the rebound deformation decreases, which indicate that backfilling mass can restrict the deformation and improve the slope stability; (2) Subsidence dominates the slope deformation in open-pit to underground mining and it increases with an increasing elevation of monitoring point; the maximum horizontal displacement occurs in the lower part of the slopes, because the backfilled part is squeezed by both the north slope and the south slope, and it has a lower elastic modulus than the previous orebody; (3) The stress and its variability near the slope foot are much larger than other places, indicating that the slope foot is most affected by stress redistribution and stress concentration may occur here; the stress at other stress monitoring points changes little, indicating that the influence of open-pit to underground mining is local; (4) The effect of underground mining on the deformation of the faults is not prominent; (5) Mining operations in near-ground part affect more on the variation of deformation and stress of pit slopes than that in deeper part. 相似文献
214.
The conventional saponification method could result in lower recoveries and artificial changes of long-chain fatty acids. The main reason is the error judgment of the intermediate layer suspended between the aqueous and organic layer during the liquid–liquid extraction process. This study shows that the intermediate layer consists of lots of medium- to long-chain carboxylic salts for their special physical and chemical properties. An improved saponification extraction method is also developed and the results show that the carboxylic salts distributed in the intermediate layer could be obtained completely, which greatly enhances the authenticity and accuracy of fatty acid analysis. Additionally, the possible reasons of formation of the intermediate layer are also discussed. 相似文献
215.
Ju Weimin Fang Hongliang Tian Xiangjun Jiang Fei Zhan Wenfeng Liu Yang Wang Zhengxing He Jianfeng Wang Shaoqiang Peng Shushi Zhang Yongguang Zhou Yanlian Jia Binghao Yang Dongxu Fu Yu Li Rong Liu Jingxian Wang Haikun Li Guicai Chen Zhuoqi 《地球科学进展》2016,31(11):1105-1110
The Paris agreement signed in April, 2016 aims to balance global anthropogenic carbon emissions and terrestrial carbon sinks by the middle of the 21st century. To fulfill this goal, it is necessary to calculate carbon fluxes of different regions reliably. The global carbon assimilation system is an effective technique for achieving this goal. The Ministry of Science and Technology of China supports the project entitled as study on the global carbon assimilation system based on multisource remote sensing data through the national key research and development programs for global change and adaptation during the thirteen-five period. This project will develop synergic inversion techniques for retrieving key parameters of biological and atmospheric cycles and for assimilating multisource remote sensing and ground based data. Then, the high resolution global carbon assimilation system coupled with an ecological model will be constructed. This system is able to assimilate jointly multisource observation data and to optimize key model parameters, photosynthesis and respiration carbon fluxes of global terrestrial ecosystems, and anthropogenic carbon emission fluxes of key regions. This system will be used to study quantitatively the spatial and temporal patterns of carbon fluxes of global terrestrial ecosystems and anthropogenic carbon emission fluxes of key regions and to identify the mechanisms driving the global terrestrial carbon sinks and sources. The outputs of this study will be helpful for the fulfillment of the key research and development programs for global change and adaptation and provide valuable data and technical support for the decision-making in China. 相似文献
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217.
秋季南黄海浮游动物分布及其影响因素 总被引:3,自引:1,他引:2
基于2007年秋季在南黄海(32°20'~37°00'N;124°E以西)进行的浮游动物及环境因子大面调查;分析了秋季南黄海浮游动物种类组成、分布特征及其影响因素;主要结果如下:共鉴定浮游动物113种(不包括25种浮游幼体);中华哲水蚤(Calanus sinicus)、强壮滨箭虫(Aidanosagitta crassa)、磷虾幼体(Euphausia larvae)和小齿海樽(Doliolum denticulatum)是秋季优势种;浮游动物丰度为(156.37±12.04)ind/m3;生物量为(172.57±10.41)mg/m3;与历史调查数据相比;本航次浮游动物丰度和生物量相对处于较高水平;磷虾幼体分布趋势与中华假磷虾(Psudeuphausia sinica)一致;说明秋季是中华假磷虾种群的一个重要的补充时期;小齿海樽在南黄海的大量出现系自身种群补充的结果;精致真刺水蚤(Euchaeta concinna)和肥胖软箭虫(Flaccisagitta enflata)主要分布在深水区;在近岸海区很少出现。中华哲水蚤、强壮滨箭虫丰度高值区倾向分布于海洋锋附近;进一步佐证了海洋锋对浮游动物的积聚作用。 相似文献
218.
CMIP5模式对中国近海海表温度的模拟及预估 总被引:2,自引:0,他引:2
基于观测和再分析资料;利用多种指标和方法评估了国际耦合模式比较计划(CMIP5)中21个模式对中国近海海温的月、季节和年际变化模拟能力。多模式集合能够再现气候平均意义下近海海温的空间分布特征;但量值上存在一定的低估。在渤海和黄海;集合平均与观测差别比较明显。在年际尺度上;与观测数据对比;模式模拟海温与Niño3指数相关性较小。中国近海海表面温度在1960-2002年有明显的升高趋势;从2003年开始增温趋缓。评估结果表明;ACCESS1.0、BCC-CSM1.1、HadGEM2-ES、IPSL-CM5A-MR、CMCC-CM、FGOALS-g2、CNRM-CM5-2、INMCM4八个模式对中国近海海温的变化有较好的模拟能力。利用ACCESS1.0、INMCM4、BCC-CSM1.1、IPSL-CM5A-MR、CMCC-CM这5个模式结果对中国近海海温未来的变化进行了预估。在RCP4.5、RCP8.5情景下;未来近100年中国近海海温有明显升高趋势;最优模式多模式集合平均增温分别可达到1.5℃、3.3℃;净热通量变化和平流变化共同促进了东海升温。 相似文献
219.
对一株分泌热稳定κ-卡拉胶酶印尼热泉菌进行了种属鉴定, 并采用响应面法对该菌发酵产酶条件进行了优化。鉴定结果表明, 该菌株属于芽孢杆菌属(Bacillus), 命名为Bacillus sp. Car19(GeneBank: KT865196)。发酵条件优化结果显示, 9个环境因子影响Bacillus sp. Car19产酶量。其中影响Bacillus sp. Car19产酶量的三个主要因素分别为培养温度、培养基中Cu2+浓度和培养基中NaCl浓度。综合次要因素对Bacillus sp. Car19产酶影响, Bacillus sp. Car19最佳产酶发酵条件为: 培养温度52.31℃、Cu2+浓度6.93 mmol/L、NaCl浓度37.03 g/L, 培养基pH为6, 接种量1%, 培养时间36h, 半乳糖浓度0.3 g/L,硝酸铵浓度7g/L, 卡拉胶浓度0.5g/L。优化后发酵上清液酶活力达到15.21 U/mL, 与优化前相比提高了1.5 倍。 相似文献
220.
Zhenjiao Jiang Gregoire Mariethoz Christoph Schrank Malcolm Cox Wendy Timms 《Hydrogeology Journal》2016,24(8):2143-2155
Coal-seam gas production requires groundwater extraction from coal-bearing formations to reduce the hydraulic pressure and improve gas recovery. In layered sedimentary basins, the coalbeds are often separated from freshwater aquifers by low-permeability aquitards. However, hydraulic connection between the coalbed and aquifers is possible due to the heterogeneity in the aquitard such as the existence of conductive faults or sandy channel deposits. For coal-seam gas extraction operations, it is desirable to identify areas in a basin where the probability of hydraulic connection between the coalbed and aquifers is low in order to avoid unnecessary loss of groundwater from aquifers and gas production problems. A connection indicator, the groundwater age indictor (GAI), is proposed, to quantify the degree of hydraulic connection. The spatial distribution of GAI can indicate the optimum positions for gas/water extraction in the coalbed. Depressurizing the coalbed at locations with a low GAI would result in little or no interaction with the aquifer when compared to the other positions. The concept of GAI is validated on synthetic cases and is then applied to the north Galilee Basin, Australia, to assess the degree of hydraulic connection between the Aramac Coal Measure and the water-bearing formations in the Great Artesian Basin, which are separated by an aquitard, the Betts Creek Beds. It is found that the GAI is higher in the western part of the basin, indicating a higher risk to depressurization of the coalbed in this region due to the strong hydraulic connection between the coalbed and the overlying aquifer. 相似文献