Multielement analysis of deep-sea sediments by inductively coupled plasma mass spectrometry

Marine sediments were dissolved by HNO3-HF-HCIO4 in a sealed container at low pressure; I-IF was evaporated in an open container and salts were dissolved in HCl by heating, then transferred to 2% HNO3 solution. A total of 45 elements, including Li, Be, So, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, TI, Pb, Bi, Th and U, were measured by inductively coupled plasma mass spectrometry (ICP-MS). Condi-tions and sample experiments showed that this procedure defines a good experimental method which has the advantages of clear interference, easy operation and reliable results. The concentrations of the 45 elements could be used for resource exploration, envi-ronmental assessment and academic research.     

顾及系统误差的地球静止轨道卫星PDOP值加权几何法定轨

对顾及系统误差的地球静止轨道（GEO）卫星几何法定轨做了初步探讨,给出顾及系统误差的GEO卫星几何法定轨数学模型,推导了参数解算公式,提出PDOP值加权的几何法定轨方法,并讨论了权函数的选取。最后以卫星钟差为例进行模拟计算。结果表明：顾及系统误差的GEO卫星几何法定轨,可大大减弱系统误差对定轨结果的影响;基于PDOP值加权的几何法定轨,可进一步提高系统参数解算精度和定轨精度。     

海上移动站精密测轨方法

将人造卫星精密定轨理论应用于海上移动站精密定轨，根据移动站的特点，建立了相应的定轨条件方程，并在此基础上利用海上移动站某次飞船发射任务跟踪数据进行了实算，给出了定轨结果和讨论。     

Yarkovsky detection opportunities. I. Solitary asteroids

We show that, over the next two decades, the current radar and optical astrometric technology is adequate to allow detection of the Yarkovsky effect acting on at least two dozen NEAs from a variety of orbital regimes and with effective diameters ranging from about ten meters up to several kilometers. The Yarkovsky effect will likely be detected for objects of rarer spectral types X, C, and E, as well as the more common S and Q. The next predicted detection of the Yarkovsky effect is for 4179 Toutatis in October 2004, which would be also the first multi-kilometer case. The Asteroid 25143 Itokawa, with a likely detection at the end of 2005, could offer an important test due to the independent “ground-truth” measurements of the asteroid mass and surface thermal inertia expected from the Hayabusa spacecraft. Earth co-orbital asteroids (e.g., 2000 PH5 or 2003 YN107) are the best placed for rapid determination of the Yarkovsky effect, and the timespan between discovery of the object and detection of the Yarkovsky effect may be as short as 3 years. By 2012, the motion of potential Earth impactor (29075) 1950 DA will likely reveal the magnitude of the Yarkovsky effect, which in turn will identify which of two possible pole orientations is correct. Vis-a-vis the 2880 impact, this new information will allow a substantial improvement in the quality of long term predictions.     

羌塘盆地胜利河海相油页岩地球化学特征及Re-Os定年

地球化学资料表明,羌塘盆地胜利河海相油页岩有机碳含量为15.05%～20.34%,平均为17.695%,灰分含量为55.23%,焦油含量为11.0%;干酪根类型为Ⅱ1或Ⅱ2型。利用Re-Os同位素对该油页岩层进行定年,得到的等时线年龄为101±24Ma。该等时线年龄比生物地层所获得的地层年龄年轻。     

微波消解-等离子体发射光谱法测定锰矿石中硅铝铁磷

锰矿经微波消解溶样处理，等离子体发射光谱法测定硅铝铁磷含量，方法基体效应小，各待测元素之间没有明显干扰。使用该法分析有证标准物质和实际样品中的SiO2、Al2O3、Fe和P，分析结果与标准值或其他常规方法测定值一致，误差均在允许范围内。方法的回收率为89％～112％，精密度（RSD，n=12）为0．55％～3．25％。与现行的单元素分析方法相比，分析周期短，适用于锰矿的日常检验。     

X射线荧光光谱法测定土壤样品中碳氮硫氯等31种组分

利用新型的ZSX Primus Ⅱ型X射线荧光光谱仪采用粉末压片法直接测定土壤样品中的C、N、S、Cl等31种元素。各元素分析晶体为N采用RX45，C采用RX61，Na、Mg采用RX25，C1、S、P采用Ge，Si、Al采用PET，其余元素均采用LiF200。结果表明，方法的检出限、精密度和准确度对绝大多数元素而言，均可满足多目标地球化学调查样品分析的质量要求：     

GEO导航卫星定轨观测模型

根据GEO导航卫星的轨道特性,给出了严密的伪距观测和载波相位观测数学模型;讨论了其轨道和星钟差的解算条件,以及多星组差定轨的可行性。结果表明:在利用伪距时,如果测站钟差已知,需要4个以上站的数据才能进行定轨和星钟解算;如果站钟、星钟钟差已知,需要3个以上站的数据才能确定轨道。在利用站间组差伪距时,须有4个以上测站的钟差信息才能进行轨道和星钟解算;利用GEO卫星与MEO(IGSO)卫星组差定轨时,需要GEO卫星钟差已知且有3组星间组差数据。利用GEO卫星载波相位观测资料,不能单独解算轨道。