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During the postgenomics era the information about genomic sequence and gene functions provides a new foundation for evolutionary biology and ecology As the first whole-genome sequenced plant Arabidopsis thaliana and its wild relatives have played a critical role in understanding the evolution of genomics and speciation Both A halleri and A lyrata are closely related to the model species A thaliana A halleri ssp gemmifera occurs in northeastern China Japan and Taiwan; while its sister A halleri ssp halleri is mainly distributed in Europe Geographical barriers such as Tienshan Mountain Range isolate these intraspecific sisters Likewise A lyrata ssp kamchatica and ssp lyrata occur in East Asia and North America respectively Such distribution patterns seem to be consistent with allopartic speciation The comparison between ancestral and extant polymorphism by multilocus can be informative about the population genetics of speciation In this study we collected and analyzed DNA sequences of 98 genes from four wild relatives of A thaliana A halleri ssp gemmifera A halleri ssp halleri A lyrata ssp kamchatica and A lyrata ssp lyrata The ancestral states of these four species were compared to each other in terms of level of genetic variation However the ancestral species at the time of speciation were substantially more polymorphic than the extant geographical populations The observations are not fully compatible with speciation by strict allopatry At some species pairs parapatric speciation seems more reasonable in speciation of Arabidopsis The 98 gene sequences are also used for the congruence test between gene genealogy and species phylogeny Only 28 genes support the species phylogeny but there are 23 genes supports another major genealogy { lyrata} thaliana Based on the phylogenetic position change of A lyrata ssp kamchatica and Ks value for each species pair suggested the recent directional gene flow between A halleri ssp gemmifera and A lyrata ssp kamchatica

阿拉伯芥是第一个完成基因体定序的开花植物，其基因体资讯提供植物学研究的重要依据；在解析阿拉伯芥属物种的亲缘关系以及种化机制等重要的演化议题时，阿拉伯芥近缘的野生物种自然成了不可或缺的关键；跟阿拉伯芥近缘的物种包括A halleri及A lyrata，其中A halleri ssp gemmifera主要分布於中国东北、日本以及台湾，与近缘的A halleri ssp halleri其分布於欧洲隔著天山及大陆的障蔽，而A lyrata ssp kamchatica主要分布於东北亚及台湾，与分布於北美五大湖的A lyrata ssp lyrata被北极圈所分隔，这样的分布模式暗示异域种化的可能。藉由多基因分析比较祖先物种与现生物种遗传歧异度的相关可提供讯息探讨种化时期的族群遗传结构，本研究针对A halleri ssp gemmifera、A halleri ssp halleri及A lyrata ssp kamchatica、A lyrata ssp lyrata四个物种，两对互为亚种的姊妹群，以阿拉伯芥为外群进行研究，在四个物种完成98个同源基因的分子序列，利用套装软体MCMCcoal来估算祖先物种的遗传变异，亦估算现生物种的核苷酸歧异度，观察到？多物种配对中祖先物种遗传多型性大於现生物种DNA歧异度，显示异域种化模型并无法完全解释阿拉伯芥属物种的种化模式，在某些物种配对间邻域种化模式应比异域种化更为可能；在基因树与物种树的比较，98个基因片段的亲缘模式只有28个是与已知物种树一致的，有23个基因其树状图支持{ lyrata} thaliana的型式，藉由kamchatica位置的变化以及估算各物种配对间的平均同义置换率，推测在A halleri ssp gemmifera与A lyrata ssp kamchatica间具有近代的单方向基因交流。

Based on the petrological and geochronological study of metamorphic complexes from the Grove Mountains, the following conclusions are reached.(1)Exsolution texture is widely found in clinopyroxene in mafic granulites. A peak metamorphic temperature of 850 C was obtained from the reintegrated compositions of exsolved clinopyroxene. The preservation of augite megacrysts suggests a single episode of high-grade metamorphism for the Grove Mountains.(2)The compositional comparison of garnet from pegmatites with that from country rocks demonstrates that garnet in pegmatites is of xenocryst origin, and late amphibolite facies metamorphism does not occur in this area.(3)The Pan-African charnockite and post-tectonic sheet-like granite were first recognized in East Antarctica. Their occurrences suggest a collisional orogeny during the Pan-African time.(4)The SHRIMP U-Pb zircon dating on various rock types indicates that the major metamorphism in the Grove Mountains occurs at c. 550 Ma, and the tectonothermal evolution terminated at c. 500 Ma. The Grenvillian granulite facies metamorphism did not develop in the studied area.(5)The Prydz belt, the second Pan-African suture within the Gondwana suppercontinent, was further comfirmed based on this study. The Gondwana suppercontinent was not formed by the simply juxtaposition of East and West Gondwana, but by the collision of several blocks during the Pan-African time.

本项目通过格罗夫山地区高级变质杂岩的变质岩石学和同位素年代学研究，获得如下重要认识：（1）发现辉石出溶结构，由此获得峰期变质温度为850 C，并根据火成普通辉石的识别确定该区只存在单相麻粒岩相变质；（2）通过伟晶岩中石榴石斑晶与围岩中石榴石的对比研究提出了石榴石的捕虏晶成因，进而确定该区不存在晚期角闪岩相变质作用；（3）在东南极首次识别出泛非期紫苏花岗岩和后构造层状花岗岩，为泛非构造热事件的碰撞造山成因提供了重要佐证；（4）对不同岩石类型的锆石SHRIMP定年精确地限定了格罗夫山地区主期变质作用发生于泛非期，～550 Ma，热事件结束于～500 Ma，年代学数据没有揭示在该区存在格林威尔期麻粒岩相变质作用的迹象；（5）进一步确认了东南极内部普里兹带的存在，它属于冈瓦纳超大陆内部的第二条泛非期缝合带，据此认为冈瓦纳超大陆并不是由东、西冈瓦纳陆块的简单拼合而成，而是多个不同块体拼合的结果。

The gaseous impurities in the alloys were well controlled with the sum of C, N and O less than 500wppm. For the first time it was found the strong interaction between Cr-Ti-CON, which reduces the mobility of Ti and CON, enhancing high-temperature strength and the aging-hardening property, and keeping the cold-work induced hardening at higher temperature. Aging-hardening could increase the tensile strength of V-4Cr-4Ti by 30% and could be utilized at 00 C for better economical performane of a vanadium structure. Hydrogen release will occur for the alloys tensile loaded at room temperature, which will affect the safety of a vanadium structure due to the resulting dimensional instability. For hydrogen embrittlement, impact toughness and fracture toughness of the alloy showed higher sensitivity than the tensile test elongation,so the toughness should be used as a new standard for the assessment of the embrittlement. Vanadium alloys were easily oxidized in air.

合金的气体杂质含量得到有效控制，C、N、O总量低于500wppm；首次发现Cr-Ti-CON之间的强相互作用，它使Ti、CON的高温可移动性降低，提高合金的高温强度、增强时效强化特性、使冷加工强化保持到更高温度；时效强化可使V-4Cr-4Ti的强度提高30%，可在低温（00C）下应用，提高构件的经济性；室温下，钒合金在拉应力的作用下，存在着氢释放，带来部件使用中的尺寸不稳定性，影响构件安全；氢脆是钒合金聚变应用的一个关键问题，合金的冲击韧性和断裂韧性表现出比拉伸延伸率更强的氢脆敏感性，应作为评价合金氢脆行为的新标准。

Take DMSO swollen treatment and DEA-SO2-DMSO decrystallization treatment for example, the X-ray diffraction and the Tobolsky's intermittent stress relaxation of treated woods were determined during soaking in water, analyzed the effects of water on crystal degree and inter-cohesion of treated woods. According to these continuous relaxation curves measured in water with different temperatures, various thermodynamic quantities were obtained by using Eyring absolute rate theory, and reviewed the chemical reactions in wood which occur in different relaxation process. For the first time quantify these crosslinkings formed in the process of tensional relaxation by using the SMCIR intermittent stress relaxation way, and defined the cross-linking reaction types. In order to find out the contribute of drying to the fixation of deformation of chemically treated wood, stress relaxation of oven-dry untreated and treated wood was measured during the process of temperature elevation and descend, then analyzed the effect of temperature change on relaxation mechanism of treated oven-dry wood. According to continuous relaxation curves of oven-dry treated wood under various constant temperature, calculated the thermodynamics of relaxation process and discussed the mechanism of molecule change in wood, at the same time, also quantified these cross-linkings produced in wood by intermittent method and on the basis of which the model of molecular change during relaxation process of chemically treated was constructed.

以DMSO膨胀处理及DEA- SO2-DMSO非晶化塑化处理为例，测定了两种处理木材在水浸渍过程中的X射线衍射及Tobolsky间歇应力松弛，分析了水对处理木材结晶度及内部凝聚力的影响；通过未处理和两种处理木材在不同温度水中的连续应力松弛测定，应用Eyring的绝对速度反应理论计算并获得了松弛过程中的各热力学量，分析了在水中松弛过程中不同阶段木材内部发生的化学反应；并首次采用SMCIR连续·不连续双曲线应力松弛法定量了轴向拉伸应力松弛过程中木材内部产生的架桥量，明确了交联反应的类型；为了了解干燥对处理木材塑性变形固定的影响，测定了未处理和两种处理绝干木材在温度下降过程和上升过程中的应力松弛，分析了温度变化对处理绝干木材应力松弛的影响；根据多个温度水平下的连续应力松弛测定曲线，计算松弛过程的热力学量，考察了绝干木材在松弛过程中内部发生的分子变化机理，同时也用间歇法定量了木材内部新形成的架桥量，并在此基础上构筑处理木材在松弛过程中内部分子构造的变化模型。

I succeeded in establishing a mycorrhizal symbiosis between S. sinuosa and transformed Ri T-DNA carrot roots for the first time. The S. sinuosa sporocarps were found not to occur as single spores, but were observed to survive in groups of sporocarps in the environment.

利用双重培养方法首次成功培养了S.sinuosa的菌根共生联合体。S.sinuosa不是单个孢子，而是以孢子果的形式存在于自然界中。S.sinuosa孢子果的萌发是从孢子果的四周伸出芽管，在侵染根段的过程中，形成大量的营养孢子。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。