NATURAL RADIATIVE LIFETIMES OF THE EXCITED-LEVELS OF THULIUM

The radiative lifetimes of eight excited levels of thulium have been measured with the method of stepwise excitation from the 4f13(F-degrees-7/2)6s2(1S0)\7/2\ ground state to the states studied using two pulsed dye lasers. Optical transients were recorded through observing fluorescences and evaluated with regard to the decay time. The accuracy of the measured lifetime values is about 10%.

The characteristics of BSRs and their derived heat flow on the profile 973 in the northeastern South China Sea

Processing of a recently acquired seismic line in the northeastern South China Sea by Project 973 has been conducted to study the character and the distribution of gas hydrate Bottom-Simulating Reflectors (BSRs) in the Hengchun ridge. Analysis of different-type seismic profiles shows that the distribution of BSRs can be revealed to some extents by single-channel profile in this area, but seismic data processing plays an important role to resolve the full distribution of BSRs in this area. BSR' s in the northeastern South China Sea have the typical characteristics of BSRs on worldwide continental margins: they cross sediment bed reflections, they are generally parallel to the seafloor and the associated reflections have strong amplitude and a negative polarity. The characteristics of BSRs in this area are obvious and the BSRs indicate the occurrence of gas hydrate-bearing sediments in the northeastern South China Sea. The depth of the base of the gas-hydrate stability zone was calculated using the phase stability boundary curve of methane hydrate and gas hydrate with mixture gas composition and compared with the observed BSR depth. If a single gradient geothermal curve is used for the calculation, the base of the stability zone for methane hydrate or gas hydrate with a gas mixture composition does not correspond to the depth of the BSRs observed along the whole seismic profile. The geothermal gradient therefore changes significantly along the profile. The geothermal gradient and heat flow were estimated from the BSR data and the calculations show that the geothermal gradient and heat flow decrease from west to east, with the increase of the distance from the trench and the decrease of the distance to the island arc. The calculated 2 heat flow changes from 28 to 64 mW/m(2), which is basically consistent with the measured heat flow in southwestern offshore Taiwan.

致密碎屑岩储层预测技术研究—以大牛地气田为例

大牛地气田是中石化在“十五”期间探明的一个大型岩性气田，成藏主要受储层发育程度的控制。储层为低孔低渗的致密碎屑岩储层，具有非均质性强，变化快的特点。由于地震资料分辨率比较低、砂泥阻抗差微弱、煤层屏蔽现象严重，造成砂体的地震响应特征不明显，加大了储层识别的难度，制约了气藏的勘探进程，因此，采用合适的储层预测技术对储层进行描述便显得尤为重要。 论文研究的总体思路是在地质沉积相研究的基础上，利用地震储层预测技术从定性—半定量—定量对储层进行雕刻。 论文总的研究内容分为地质沉积相研究和地震储层预测技术研究两大部分。 地质沉积相研究是地震预测的基础。利用地质资料和钻井资料对沉积相进行研究，证实在大牛地气田的西南部，发育二叠系山西组、下石盒子组的2条主河道，砂体纵向相互叠置，平面的分布受河道的控制。 在沉积相研究的基础上，利用地震预测技术对大牛地气田下石盒子组和山西组的储层进行预测，概括起来，有3大核心技术：核心技术之一：相控地震属性分析技术，对储层的宏观分布从地震上进行识别；核心技术之二：基于地质统计学理论的储层反演描述技术，对储层进行半定量的预测；核心技术之三：多信息融合的储层建模技术，对储层的岩性、物性、含气性进行定量的预测。 论文的创新点有3点：1、利用地震属性定性预测储层分布，通过岩石地球物理分析及地震属性优化，筛选出不同层系反映河道砂体的敏感地震属性；2、利用地震反演对储层半定量预测， Gr和中子的重构曲线反演和中子和密度曲线重构反演加大了岩性和气层识别的力度，克服了砂泥阻抗差微弱的困难，探索出一条煤系地层储层半定量预测的新方法；3、储层建模研究将沉积相研究和地震预测技术进行了有机的融合，把沉积相，属性预测和地震反演成果作为输入，定量的对储层的岩性、物性、含气性进行预测，达到了量化储层的目的。 通过上述研究，从宏观—微观，从定性—定量实现了对致密碎屑岩储层的预测。

Two new diterpenoids from Isodon rubescens

Two new diterpenoids taibairubescensin A (1) and B (2) have been isolated from Isodon rubescens. The structures of compound 1 and 2 were elucidated as 2 beta,3 beta-diacetoxy-11 beta,13 alpha-dihydroxy-ent-kaur- 16-en-15-one (1) and 3 beta,11 beta-diacetoxy-2 beta,6 alpha-dihydroxy-ent-kaur-16-en-15-one (2) on the basis of spectroscopic analysis.

动基座机器人的末端受限鲁棒跟踪控制

结合具有扰动基座末端受限机器人的动力学特性，提出了虚构线性不确定系统的匹配模型概念．通过引入线性不确定系统的鲁棒跟踪控制器设计方法，发展了一种新的受约束机器人的力鲁棒跟踪控制方法．文中给出了动基座ＰＵＭＡ５６２机器人的实验结果。

内蒙古克什克腾旗小东沟斑岩型钼矿床的成矿作用

In this paper, the Xiaodonggou porphyry molybdenum deposit located in the Xarmoron molybdenum metallogenic belt is chose as the research area. We have analyzed the petrology of the Xiaodonggou pluton in detail and made chemical analysis of the major and trace elements, Rb-Sr and Sm-Nd isotope, common lead isotope and SHRIMP zircon U-Pb dating et al; in the other hand, we use the molybdenite to make common lead analysis and Re-Os isotopic dating. The Xiaodonggou pluton is rich in silicon, potass, zirconium, and low in REE. In addition, it has no minus Eu abnormity and show a isotopic composition high in εNd(t) and low in Sri, indicating its magma origining from the melting of juvenile thicken lower crust. In the meanwhile, it contained the features of high temperature, quick melting, quick segregation and quick emplacement. The common lead analysis of the pluton orthoclase and molybdenite show that the former transfer from orogen to mantle and the latter come from mantle, which is consistent to the molybdenite sulfur isotopic and quartz oxygen isotopic composition, demonstrating that the rock and ore-forming materials of deposit having different sources, magma from the lower crust mixing with mantle fluid. In plus, we use the physical experiments results of the water-magma reaction to explain the interaction of magma and mantle fluid. In the deep crust, these two systems uplifted in a immiscible state; when they reached low depth, the stream film between fluid-magma collapsed, and the magma was broken into small agglomerates by the fluid, then they mixed thoroughly. The SHRIMP zircon U-Pb dating gave a result of 142±2Ma and the molybdenite Re-Os dating result is 138.1±2.8Ma, corresponding to the big tectonic transition period of 140Ma, when the major stress field changing from south and north to west and east. At this time, the Da Hinggan ling ranges area was under an extensive background, underplating proceeded and mantle materials could add into the magmas forming in the lower crust. So, from the above analysis, we propose the following model for the Xiaodonggou porphyry molybdenum deposit: in the early Cretaceous period, the Da Hinggan ling ranges area was under a extensive background, the adding of mantle fluid containing ore materials into heated lower crust made it melting to produce magmas. Following more mantle fluid got into the magma room and urged the magma to segregate from the source quickly. The fluid and magma uplifted together, when they arrived at shallow depth, the fluid-magma became unstable and the latter was broken into many small agglomerates with fluid connecting them in the interspaces. Because of the H+, K+ and various elements existing in the fluid, it would reacted with the magma and the rock through alteration and ore minerals crystallized out, forming the Xiaodonggou porphyry deposit with disseminated mineralization phenomenon.

吉林西部向海湿地环境退化及驱动机制研究

向海湿地位于半干旱的吉林西部平原区，特殊的地理位置和水文条件决定了湿地处于动态变化之中。在自然和人为驱动影响下，系统结构和功能发生明显的退化趋势，湿地面积缩小、调节功能削弱，区域荒漠化发展迅速。通过对湿地发育的环境背景条件分析，剖析了湿地退化的现状及驱动机制，水陆界面的脆弱性是湿地退化的环境背景条件，而气候干旱化、上游水的大量截流、水利工程设施及土地资源的不合理开发利用等自然、人为因素的耦合作用．加速了湿地的退化过程。基于湿地退化的现状和驱动机制，河流湿地退化的恢复必须从湿地的水文功能出发，考虑水资源的循环和转化．制定水资源综合利用方案及生态技术和生态工程措施。

Franck-Condon simulation of the photoelectron spectrum of SO2- including Duschinsky effects

A theoretical method to calculate multidimensional Franck-Condon factors including Duschinsky effects is described and used to simulate the photoelectron spectrum of the anion SO. Geometry optimizations and harmonic vibrational frequency calculations have been performed on the XA(1) state of SO2 and (XB1)-B-2 state of SO2. Franck-Condon analyses and spectral simulation were carried out on the first photoelectron band of SO2. The theoretical spectra obtained by employing CCSD(T)/6-31 I+G(2d,p) values are in excellent agreement with the experiment. In addition, the equilibrium geometric parameters, r(c)(OS) = 0.1508 +/- 0.0005 nm and theta(e)(O-S-0) = 113.5 +/- 0.5 degrees, of the (XB1)-B-2 state of SO2, are derived by employing an iterative Franck-Condon analysis procedure in the spectral simulation. (c) 2005 Elsevier B.V. All rights reserved.