南海ODP1144也微玻璃陨石物理地球化学特征及成因和气候效应综合研究

澳大利亚-东南亚散落区覆盖着地球表面的1／10，是迄今散落面积最大，最年轻，成分最复杂的散落区。澳一亚群微玻璃陨石已经在印度洋、太平洋西部、Sulu海、Celebes海和菲律宾海的40个深海岩心中被发现。澳-亚（微）玻璃陨石及撞击残骸的分布区域以Indochina为中心呈放射状或者稍微同心状分布模式，因而许多研究者认为Indochin。是澳亚群的撞击坑所在地。南海是西太平洋最大的边缘海之一，地处太平洋板块、印度洋板块及欧亚板块的接合部位，具有典型的边缘海特点—对古海洋学变化具有放大作用，南海的北部陆缘保存有完好的晚更新世地层，记录着丰富的海洋地质和古环境演化的信息。同时南海在澳大利亚-东南亚散落区范围内，距离假定Indochina的撞击位置〔12°N，106°E）较近，对于澳亚群微玻璃陨石的研究具有重要的地理优越性。南海海域澳亚群（微）玻璃陨石事件现今研究较少，对于南海含微玻璃陨石孔位的综合研究是近年来的热点和重点。南海ODPI144孔位于20°3.18'N，117'25.14'E，取得了1.1Ma以来连续的沉积地层样品，沉积物中含有丰富的微玻璃陨石，对含有微玻璃陨石层位加密取样，取样间距为1一Zcm。微玻璃陨石主要赋存在386.17-386.27mcd（合成深度米数：meter of composed depth，以下简称m），样品中共挑出完整的微玻璃陨石969颗，不规则碎片1543颗，在柱样状386.23m处微玻璃陨石的含量最为丰富，共发现完整颗粒194颗，不规则碎片239颗。同时在微玻璃陨石的挑选的基础上，对孔位中有孔虫进行了初步研究，挑选出其中的优势种属袋拟抱球虫或者红拟抱球虫。本文通过对南海ODPll44孔微玻璃陨石赋存层位、物理性质、地球化学特征等综合研究，结合有孔虫碳氧同位素研究结果进行分析，本文研究主要取得了以下几点认识：前人对于澳亚群微玻璃陨石的分类问题，根据物理性质和地球化学特征，划分了两种类型的微玻璃陨石，即普通型和瓶绿色微玻璃陨石，对于南海ODPI144孔微玻璃陨石物理性质和化学特征的综合研究，表明了南海沉积物中的微玻璃陨石为澳亚群普通型微玻璃陨石。根据微玻璃陨石表面特征，可能微玻璃陨石在沉积过程中受到了一定的溶蚀作用，但是其空气动力学过程目前仍不清楚。通过微玻璃陨石的物理性质、主量元素特征以及微量元素特征研究，表明微玻璃陨石的主要成因是部分熔融作用的产物，与闪电熔岩和撞击玻璃具有非常明显的类似特征，对于南海ODP1144孔微玻璃陨石的主量元素、微量元素及稀土元素等地球化学特征的综合研究，表明微玻璃陨石母岩为地球岩石，尤其是与上地壳沉积岩石类型密切相关。微玻璃陨石是由两种或者两种以上的母源物质混合而成的。地球化学特征表明：ODPll44孔及整个澳亚群普通型微玻璃陨石的原始母源物质可能是一些很年轻的（未遭受淋滤作用）碎屑沉积岩，另一种母源成份可能是粘土或者杂砂岩。这两种结果仅仅是靶区母源物质的两种成份，可能还存在其它成份，例如白云石成份的出现，这些结果从一个侧面同样反映了澳亚散落区微玻璃陨石母源物质的成份复杂性。通过ODP1144孔微玻璃陨石的研究，结合南海和澳亚群其它孔位的资料对比，发现在南海及一些等高分辨率岩心中的微玻璃陨石的赋存层位主要在B/M之下，而其它地区的低分辨率孔位则位于界线层或者之上。其原因可能是沉积过程中生物扰动和沉积地磁的获得深度（PDRM）影响了微玻璃陨石和B/M界线的位置。生物扰动对微玻璃陨石的影响最高可达8cm，沉积速率强烈的影响PDRM获得深度。沉积速率较低的孔位，其PDRM的值异常的高，而沉积速率较高的孔位，PDRM深度平均约为16cm。生物扰动以及 PDRM的获得深度影响了微玻璃陨石和地磁事件地层位置，上述原因直接导致了微玻璃陨石沉积年龄探讨的复杂性。根据本文的研究结果和综合资料对比，澳亚群微玻璃陨石的撞击地点可能存在着很大的不确定性，对南海ODP1144孔微玻璃陨石研究表明，其源坑位置距离现今预测Indochina的位置向东北方向偏移，偏移的程度还需要南海更多的孔位的研究结果，坑的半径大小可能在50-140km之间，靠近我国南方的东南亚地区应该是撞击地点的最可能区域。南海ODP1144孔有孔虫碳氧同位素研究结果表明，澳亚群微玻璃陨石事件对于南海地区存在着一定的气候效应，在该时期，由于撞击事件的发生，导致了该区有一次短暂的气候变冷事件，气温约下降了4℃，持续的事件约2ka。这一证据表明了澳亚微玻璃陨石事件对于南海的气候具有显著的影响。根据上述所取得的认识，结合当前微玻璃陨石的研究现状，本文提出我国南方包括南海应该是今后澳亚群微玻璃陨石的重点地区，应该加强对该区域的综合研究程度，在该区进一步寻找增加南海中含微玻璃陨石赋存层的孔位资料。通过本文的对南海ODPI144孔微玻璃陨石的类型、成因以及撞击事件的气候效应探讨，这些成果对于今后在该区域的研究甚至整个澳亚群的研究都起到了一定推动作用，为今后的研究工作提供了一个全新的思路。

Characterization of iron atoms in the framework of MFI-type zeolites by UV resonance Raman spectroscopy

Silicalite-I, ZSM-5, and Fe-ZSM-5 zeolites prepared from two different silicon sources are characterized by UV resonance Raman (UVRR) spectroscopy, X-ray diffraction (XRD), electron spin resonance (ESR), and UV/visible diffuse reflectance spectroscopy (UV/Vis DRS). A new technique for investigating zeolitic structure, UV resonance Raman spectroscopy selectively enhances the Raman bands associated with framework iron atoms incorporated into MFI-type zeolites, and it is very sensitive in identifying the iron atoms in the framework of zeolites, while other techniques such as XRD, ESR, and UV/Vis DRS have failed in uncovering trace amounts of iron atoms in the framework of zeolites. (C) 2000 Academic Press.

北京市中学生考试焦虑状况及其相关因素分析

In order to analyze the test anxiety of Beijing's high school students, relevant factors affecting test anxiety and how those factors have effect on the test anxiety of those high school students, a cross-sectional study had been conducted among 2,089 students randomly selected from 15 high schools in Beijing, using the Test Anxiety Scale（TAS）, Parenting Style Scale (PSS) and Academic Aggregate Graphic (AAG). Five months later, 194 students from one of those high schools were retested with TAS with students remaining anonymous. In the retest, the classes and birth dates of those students were strictly matched. This paper is composed of three parts to examine the issue. The first part examines the test anxiety among high school students in Beijing and establishes the model; the second part conducts a comparative study of issues related to test anxiety and academic performance; the third part examines the factors affecting test anxiety and establishes the model. Results showed that: 1. The reliability and validity of TAS are satisfied and can meet survey requirement. The 25-item version of TAS turned out to have equal or even better performance compared with the original 37-item version. 2. Incidence of test anxiety in high schools of Beijing: 57.9 percent of samples have an overall score at or higher 15. 55 percent of male student samples have a score at or higher than 15 while that for female student samples is 61 percent. A score of 20 refers to fairly serious test anxiety and 31.9 percent of samples have a score over 20. 28.1 percent of the male student samples have a score of over 20 while that for female student samples is 35.9 percent. 3. The effect of grade and sex and the interaction between the two factors are statistically significant. Female students have higher test anxiety than male students and the level of test anxiety varies from grade to grade. 4. Samples are divided into two groups, one with test anxiety and the other without. The academic performance gap between the two groups is very significant. There is a significant negative correlation between academic score and test anxiety. 5. There is a negative correlation between test anxiety and mastery goal orientation and a positive correlation between test anxiety and performance goal orientation. Students with higher academic self-efficiency have lower test anxiety. The more one thinks study is valuable, the lower his/her test anxiety is. Those whose parents communicate smoothly with them have lower test anxiety. Those whose parents have an inconsistent communication style have higher test anxiety. 6. Achievement goal is mediate variable for the effect of lack of values on test anxiety. 7. The indirect effect of introduction of achievement goal and parenting style, including communication, monitoring and communication consistence, on test anxiety is significant. Key words: Test anxiety，reliability, validity, self-efficiency，parenting style，achievement goal orientation, academic values, academic score

Specialization of Perceptual Processes

In this report, I discuss the use of vision to support concrete, everyday activity. I will argue that a variety of interesting tasks can be solved using simple and inexpensive vision systems. I will provide a number of working examples in the form of a state-of-the-art mobile robot, Polly, which uses vision to give primitive tours of the seventh floor of the MIT AI Laboratory. By current standards, the robot has a broad behavioral repertoire and is both simple and inexpensive (the complete robot was built for less than $20,000 using commercial board-level components). The approach I will use will be to treat the structure of the agent's activity---its task and environment---as positive resources for the vision system designer. By performing a careful analysis of task and environment, the designer can determine a broad space of mechanisms which can perform the desired activity. My principal thesis is that for a broad range of activities, the space of applicable mechanisms will be broad enough to include a number mechanisms which are simple and economical. The simplest mechanisms that solve a given problem will typically be quite specialized to that problem. One thus worries that building simple vision systems will be require a great deal of {it ad-hoc} engineering that cannot be transferred to other problems. My second thesis is that specialized systems can be analyzed and understood in a principled manner, one that allows general lessons to be extracted from specialized systems. I will present a general approach to analyzing specialization through the use of transformations that provably improve performance. By demonstrating a sequence of transformations that derive a specialized system from a more general one, we can summarize the specialization of the former in a compact form that makes explicit the additional assumptions that it makes about its environment. The summary can be used to predict the performance of the system in novel environments. Individual transformations can be recycled in the design of future systems.

Informações meteorológicas de Passo Fundo, RS: junho de 2006.

2006

Research into error recovery for sensory robots

Lee, M., Barnes, D. P., Hardy, N. (1985). Research into error recovery for sensory robots. Sensor Review, 5 (4), 194-197.

Evaluating the contribution of the clinical librarian to a multidisciplinary team

Urquhart, C., Turner, J., Durbin, J. & Ryan, J. (2006). Evaluating the contribution of the clinical librarian to a multidisciplinary team. Library and Information Research, 30(94), 30-43. Sponsorship: NHS Trusts in North Wales

Finding Rough Set Reducts with SAT.

R. Jensen, Q. Shen and A. Tuson, 'Finding Rough Set Reducts with SAT,' Proceedings of the 10th International Conference on Rough Sets, Fuzzy Sets, Data Mining and Granular Computing, LNAI 3641, pp. 194-203, 2005.

A cognitive approach to identifying measurable milestones for programming skill acquisition

Mead, J., Gray, S., Hamer, J., James, R., Sorva, J., Clair, C. S., and Thomas, L. 2006. A cognitive approach to identifying measurable milestones for programming skill acquisition. SIGCSE Bull. 38, 4 (Dec. 2006), 182-194.

Dialogic Signals In Argumentative Discussions of Advanced Polish Learners Of English

The first part of the paper deals with characteristics of classroom interaction as a type of institutional talk in a conversational analytic perspective. Next, the thesis is discussed concerning developing learners' interactional competence to foster learner discursive independence in argumentative discussions in English as a foreign language. Finally, after a short review of dialogic signals, the article presents a preliminary analysis of selected dialogic signals: evaluating reformulations and piggybacking as the ways of achieving reciprocity in argumentative discussions.

Practical assessment of hardware limitations on power aware wireless sensor networks - An anti-windup approach

This work considers the effect of hardware constraints that typically arise in practical power-aware wireless sensor network systems. A rigorous methodology is presented that quantifies the effect of output power limit and quantization constraints on bit error rate performance. The approach uses a novel, intuitively appealing means of addressing the output power constraint, wherein the attendant saturation block is mapped from the output of the plant to its input and compensation is then achieved using a robust anti-windup scheme. A priori levels of system performance are attained using a quantitative feedback theory approach on the initial, linear stage of the design paradigm. This hybrid design is assessed experimentally using a fully compliant 802.15.4 testbed where mobility is introduced through the use of autonomous robots. A benchmark comparison between the new approach and a number of existing strategies is also presented.