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971.
采用光学显微镜、X射线荧光光谱(XFS)和电感耦合等离子体质谱(ICP-MS)等方法测定了大同煤田塔山井田太原组5号煤的宏观煤岩类型、显微煤岩类型和地球化学参数,探讨了煤的煤岩学、煤地球化学及煤相特征,系统地分析了煤层的原始成煤泥炭沼泽环境及演化规律。研究结果表明,5号煤层有4种煤相类型,即湖沼相、泥炭沼泽相、潮湿森林沼泽相和较干燥森林沼泽相,相应表现为湖泊、障壁岛后潟湖、上三角洲平原和洪泛盆地含煤沉积体系特征。煤层自下而上存在5次比较明显的沉积旋回韵律,与之相随的水介质环境也发生了相应的海陆、咸水、淡水交替变化,从而形成了一套以陆相为主、海陆交互的成煤泥炭沼泽环境,沉积环境逐渐从海相、海陆过渡相向陆相演化。 相似文献
972.
Jan Petrich 《Ocean Engineering》2011,38(1):197-204
Attitude control systems for autonomous underwater vehicles are often implemented with separate controllers for pitch motion in the vertical plane and yaw motion in the horizontal plane. We propose a novel time-varying model for a streamlined autonomous underwater vehicle that explicitly displays the coupling between yaw and pitch motion due to nonzero roll angle and/or roll rate. The model facilitates the use of a multi-input multi-output H∞ control design that is robust to yaw-pitch coupling. The efficacy of our approach is demonstrated with field trials. 相似文献
973.
用乙酰微小杆菌(Exiguobacterium acetylicum)完整细胞作为酶源,催化鸟苷和胸腺嘧啶合成抗艾滋病药物关键中间体5-甲基尿苷,并对影响菌体生长和5-甲基尿苷转化率的因素进行了考察。采用紫外诱变方法获得高表达核苷磷酸化酶菌种,使5-甲基尿苷的转化率提高到了75.8%;对培养基进行了碳源和氮源的优化,结果表明,3 g/L葡萄糖、20 g/L玉米浆、4 g/L NH4Cl有利于菌体生长;通过响应曲面(Response Surface Methodology,RSM)法获得了较为合适的转化条件:0.03 g/L MnSO4加入到pH值为8.0的磷酸缓冲液,两种底物浓度均为67 mmol/L,反应温度为56℃。 相似文献
974.
975.
基于高分辨率遥感卫星数据提取DEM技术已广泛应用于地学研究中,但基于IRS-P5立体像对提取DEM的研究应用目前还比较少。主要介绍了IRS-P5卫星获取立体像对的工作原理,立体像对提取DEM原理、方法及精度评定,列举了该技术在地学研究中的应用实例及其应用前景以及存在的问题。结果表明,在良好的地面控制点的支持下,IRS-P5立体像对提取的DEM平面和高程精度均可满足国家山地1∶1万地形图测图规范要求,在地学研究中具有广阔的应用前景。 相似文献
976.
羌资5井位于藏北羌塘盆地,该井钻遇二叠系龙格组及展金组。储层主要是龙格组及展金组中的碳酸盐岩,其主要岩性是微晶灰岩、粒屑灰岩、生物屑灰岩、角砾灰岩以及粉/细晶白云岩。储集空间主要为孔隙,另发育裂缝。孔隙可分为粒间孔、粒间溶孔、粒内溶孔、晶间孔及晶间溶孔、沿缝合线发育的溶孔;裂缝可分为构造缝、压溶缝和溶蚀缝。物性数据显示,孔隙度变化范围在0.3%~2.3%,平均值为1.31%;渗透率变化范围在(0.0034~0.0062)×10-3μm2,平均值为0.0044×10-3μm2,储层评价为差。影响碳酸盐岩储集物性的因素主要是成岩作用和构造作用。有利成岩作用主要是压溶作用、溶蚀作用、白云石化作用;不利的影响因素是压实作用、胶结作用、重结晶作用、硅化作用等。 相似文献
977.
用GMS-5气象卫星遥测地面太阳总辐射 总被引:3,自引:0,他引:3
由GMS-5静止气象卫星测量的可见先通道的行星反照率。根据地球-大气系统的物理模式反演得到了地面的太阳辐射,该模式以平均气候模式和晴天的气溶胶光学厚度计算晴天的大气吸收、分子和气溶胶散射,其它情况下的散射由行星反照率和晴天的地表反照率推算而得。模式中考虑了水汽和气溶胶的变化对地表太阳辐射的影响。卫星反演的地表太阳辐射与地面观测结果的相关系数高达95%以上。日平均方差约为10%。从比较的结果来看。卫星反演的每时次地面太阳辐射的精度较已有的结果有所提高。 相似文献
978.
Alexie Heimburger Mickael Tharaud Fabrice Monna Rémi Losno Karine Desboeufs Elisabeth B. Nguyen 《Geostandards and Geoanalytical Research》2013,37(1):77-85
The fifth version of natural river water certified reference material, SLRS‐5 (National Research Council – Conseil National de Recherches Canada), is commonly used to control the quality of major and trace element measurements. Concentrations of silicon and thirty‐one uncertified trace elements have been reported for the certified reference material SLRS‐4, but they are not yet available for SLRS‐5. Here, SLRS‐5/SLRS‐4 ratios were deduced from SLRS‐5 and SLRS‐4 measurements by inductively coupled plasma‐atomic emission spectrometry and high‐resolution inductively coupled plasma‐mass spectrometry for certified elements and thirty‐five uncertified elements (rare earth elements, B, Bi, Br, Cs, Ga, Ge, Hf, Li, Nb, P, Pd, Rb, Rh, S, Sc, Si, Sn, Th, Ti, Tl, Y). Both reference materials were measured directly one after the other, so that calculated elemental ratios would not be notably influenced either by calibration uncertainties or by eventual long‐term instrumental drift. The computed ratios are in good agreement with those deduced from the certified values. We also report concentrations for thirty‐three uncertified elements in SLRS‐5 by combining the measured SLRS‐5/SLRS‐4 ratios and the published SLRS‐4 values. The resulting new data set provides target SLRS‐5 values, which will be useful in quality control procedures. 相似文献
979.
During the period of 3—5 August 1996(for short “96.8”),an extraordinary rainstorm eventoccurred in Henan,Hebei and Shanxi Provinces in China,resulting in severe flood catastrophe.Synoptic analyses indicated that the stable gross col field and the interaction between a northwardmoving typhoon(down into low pressure)and its east lateral Pacific subtropical high were thelarge-and meso-scale circulation conditions of the “96.8” extraordinary rainstorm.The mesoscaletyphoon-low and its specific dynamical and thermodynamical structures were directly related to thisrainstorm event.The nonhydrostatic version of mesoscale numerical model MM5 was used toconduct investigation of numerical simulation for this case.The simulation with the full physicalprocesses of nonhydrostatic version MM5 was basically possessed of a capability to reproduce thegenesis,development and evolution of the large-scale and meso-α scale synoptic systems.Thesimulative results using a two-way interactive nesting procedure revealed that the typhoon-low waspossessed of an intensive coupled mechanism between the dynamical and thermodynamical fields,namely,the developing typhoon-low was possessed of a structure of the.cyclonic vorticity columnwith warm center and high humidity,the vorticity column on the lower levels was the moistconvective instability and negative moist potential vorticity structure:the intensive ascendingvertical motion and the intense divergence on upper levels and intensive convergence on the lowerlevels as well as the development of the convective cloud cluster were intercoupling:the intensesouthern wind jet companied by the typhoon-low was not only the interaccompanying andintercoupling condition of the development and maintenance of the typhoon-low and convectivecloud cluster,but also was the transportable belt of the moisture source and heat energy of the“96.8”extraordinary rainstorm.The analysis of simulative results of precipitation indicated thatthe distribution of the rainfall belt and rainfall rate was basically consistent with that of theobservation in spite of some rainfall centers less or larger than those of the observation for coarseor fine mesh domain,respectively. 相似文献
980.
1 IntroductionThepolarregionisanimportantareaforenergeticcouplingbetweensolarwindandearth’smagnetosphere .Thecuspisthedirectpathforsolarwindpenetratingintothemagnetosphereorevenintotheionosphereanditalsoisaconvergentregionforalotofmagnetosphericbounda… 相似文献