大别山太湖地区榴辉岩变质P-T条件及构造意义

As far as the architecture of the south Dabie metamorphic terrain is concerned, there have been lots of different opinions for a long time. Wang et al. (1990, 1992) thought of it was a continuous terrain. Okay (1993) held that it consistes of two different tectonic terrains: the 'hot' and 'cold' eclogite belt. Liu and Wang (1998) held that it is composed of different metamorphic blocks through 'melange' in depth. For this reason, we have choiced Hualiangting reservoir of Taihu county as the study area treat eclogite as the investigated objection in this thesis, and employ the detailed 1 :10000 geological mapping, methods of Petrography and electonic probe anaylsis to probe into the architecture of the south Dabie metamorphic terrains. In the light of the eclogite occurrenc in the field, the analysis of Petrography, the research on metamoiphic P-T path and condition of the peak metamorphic P-T condition, the eclogite in the Taihu area of Dabieshan have been classified into three types eclogite from the south to the north: The zhujiachong type eclogite; The Daba type eclogite; (3) The Jinheqiao type eclogite, their mineral composition, structure, and mineral component vary continuously. These eclogites have the same rnetamoiphic stages, P-T evolution pattern, and their peak P-T condition varies continuously. The zhujiachong type eclogite is formed in the high pressure metamoiphic environment. The Jinheqiao type eclogite is formed in the typical ultra-high pressure environment. The Daba type eclogite is formed in the transformed metamorphic environment between high pressure and ultra-high pressure metamorphism. All these evidences show that the south Dabie metamorphic terrain is a continuous metamorphic block and no large fault ever existed.

基于结构分析地震资料去噪方法研究

With the development of oil and gas exploration, the exploration of the continental oil and gas turns into the exploration of the subtle oil and gas reservoirs from the structural oil and gas reservoirs in China. The reserves of the found subtle oil and gas reservoirs account for more than 60 percent of the in the discovered oil and gas reserves. Exploration of the subtle oil and gas reservoirs is becoming more and more important and can be taken as the main orientation for the increase of the oil and gas reserves. The characteristics of the continental sedimentary facies determine the complexities of the lithological exploration. Most of the continental rift basins in East China have entered exploration stages of medium and high maturity. Although the quality of the seismic data is relatively good, this areas have the characteristics of the thin sand thickness, small faults, small range of the stratum. It requests that the seismic data have high resolution. It is a important task how to improve the signal/noise ratio of the high frequency of seismic data. In West China, there are the complex landforms, the deep embedding the targets of the prospecting, the complex geological constructs, many ruptures, small range of the traps, the low rock properties, many high pressure stratums and difficulties of boring well. Those represent low signal/noise ratio and complex kinds of noise in the seismic records. This needs to develop the method and technique of the noise attenuation in the data acquisition and processing. So that, oil and gas explorations need the high resolution technique of the geophysics in order to solve the implementation of the oil resources strategy for keep oil production and reserves stable in Ease China and developing the crude production and reserves in West China. High signal/noise ratio of seismic data is the basis. It is impossible to realize for the high resolution and high fidelity without the high signal/noise ratio. We play emphasis on many researches based on the structure analysis for improving signal/noise ratio of the complex areas. Several methods are put forward for noise attenuation to truly reflect the geological features. Those can reflect the geological structures, keep the edges of geological construction and improve the identifications of the oil and gas traps. The ideas of emphasize the foundation, give prominence to innovate, and pay attention to application runs through the paper. The dip-scanning method as the center of the scanned point inevitably blurs the edges of geological features, such as fault and fractures. We develop the new dip scanning method in the shap of end with two sides scanning to solve this problem. We bring forward the methods of signal estimation with the coherence, seismic wave characteristc with coherence, the most homogeneous dip-sanning for the noise attenuation using the new dip-scanning method. They can keep the geological characters, suppress the random noise and improve the s/n ratio and resolution. The rutine dip-scanning is in the time-space domain. Anew method of dip-scanning in the frequency-wavenumber domain for the noise attenuation is put forward. It use the quality of distinguishing between different dip events of the reflection in f-k domain. It can reduce the noise and gain the dip information. We describe a methodology for studying and developing filtering methods based on differential equations. It transforms the filtering equations in the frequency domain or the f-k domain into time or time-space domains, and uses a finite-difference algorithm to solve these equations. This method does not require that seismic data be stationary, so their parameters can vary at every temporal and spatial point. That enhances the adaptability of the filter. It is computationally efficient. We put forward a method of matching pursuits for the noise suppression. This method decomposes any signal into a linear expansion of waveforms that are selected from a redundant dictionary of functions. These waveforms are chosen in order to best match the signal structures. It can extract the effective signal from the noisy signal and reduce the noise. We introduce the beamforming filtering method for the noise elimination. Real seismic data processing shows that it is effective in attenuating multiples and internal multiples. The s/n ratio and resolution are improved. The effective signals have the high fidelity. Through calculating in the theoretic model and applying it to the real seismic data processing, it is proved that the methods in this paper can effectively suppress the random noise, eliminate the cohence noise, and improve the resolution of the seismic data. Their practicability is very better. And the effect is very obvious.

亚洲地形和海陆分布变化对东亚环境格局形成演化的作用：数值模拟与地质记录对比

Earlier studies on the distribution of geological environmental indicators in China revealed drastic changes from a zonal climate pattern (planetary-wave-dominant pattern) in the Paleogene to a monsoon-dominant one in the Neogene, which suggested an inception of the initial East-Asian summer monsoon. However, there are different views about the time and causes of the changes.Here, we attempt to compile a series of paleoenvironmental maps based on newly collected climate indicators from the literatures and chronologically constrained evidence of geological maps in order to re-examine the temporal and spatial evolution of climate belts in China during the Cenozoic with special emphasis on the changes of the arid belt. These indicators include mammalian fauna, coal, carbonate concretions, jarosite, salt, gypsum deposits and pollen assemblages etc, with chronological controls that we believe reliable. Pollen assemblages and mammalian fauna have been classified into three categories (arid, semi-arid/sub-humid, humid) to reflect the intensity of aridity/humidity. Salt, jarosite and gypsum deposits are classified as the arid indicators. Carbonate concretions and coal are classified into the semi-arid/sub-humid and humid one respectively. Paleoenvironmental maps at 8 time slices have been reconstructed. They are the Paleocene, Eocene, Oligocene, Miocene, Early Miocene, Middle Miocene, Late Miocene and Pliocene.And furthermore, we attempt to use IAP^AGCM to simulate the evolution of climate belts in emphasizing on the changes of the rain band, and compare the results with the paleoenvironmental maps in order to examine the causes of the drastic paleoenvironmental changes near the Oligocene/Miocene boundary. 36 sensitive numerical experiments are carried out using the IAP__AGCM to analyze the impacts of the uplift of the Himalayan-Tibetan complex, shrinkage of the Paratethys Sea, expansion of the South China Sea and the development of the polar ice sheets on rain band in China.The main conclusions are as follows:The obtained results essentially confirm the earlier conclusions about a zonal climate pattern in the Paleogene and a different pattern in the Neogene, and illustrate that a monsoon-dominant environmental pattern with inland aridity formed by the Early Miocene, which is temporally consist with the onset of eolian deposits in China.Cenozoic cooling and the formation of polar ice sheets are unlikely the main causes to the changes of environmental patterns mentioned above in China. But northern hemispheric cooling and the ice-sheets can intensify the Siberian High Pressure, and strengthen the winter monsoon circulations and enhance the aridity in the west part of China. These results support the earlier studies.Shrinkage of the Paratethys Sea and uplift of the Himalayan-Tibetan complex played important roles in strengthening the East Asian monsoon and induceing the above changes of environmental pattern, which is consistent with the earlier studies. Furthermore, "the monsoon-dominant pattern" appears when the Himalayan-Tibetan complex reaches to about 1000-2000 meters high and the Paratethys Sea retreats to the Turan Plate.4) Expansion of the South China Sea is another significant factor that drives the evolution of environmental patterns. We believe that the above three factors co-act and drive the change of the environmental patterns from a planetary-wave-dominant one to a monsoon-dominant one. However, the impacts of each factor vary by regions. The uplift mainly increases the humidity in Southwestern China and the aridity in northwestern country. The shrinkage mainly increases the humidity in Northern China and also enhances the aridity in the northwestern country. The expansion greatly increases the humidity in the south part of China.

克拉2异常高压气藏地质特征及开发技术研究

Kela-2 gas field in Tarim Basin is the main supply source for West-to-East Pipeline project, also the largest abnormally-pressured gas field discovered in China currently. The geological characterization, fine geological modeling and field development plan are all the world-class difficult problems. This work includes an integrated geological and gas reservoir engineering study using advanced technology and approaches, the scientific development plan of Kela-2 gas field as well as the optimizations of the drilling, production and surface schemes. Then, it's expected that the Kela-2 gas field can be developed high-efficiently.Kuche depression is one part of the thrust belt of the South Tianshan Mountains, Kela-2 field is located at the Kelasu structural zone in the north of Kuche depression. The field territory is heavily rugged with deeply cut gullies, complex geological underground structure, variable rock types, thrust structure development. Therefore, considerable efforts have been made to develop an integrated technique to acquire, process and interpret the seismic data in complicated mountain region. Consequently a set of seismic-related techniques in the complicated mountain region has been developed and successfully utilized to interpret the structure of Kela-2 gas field.The main reservoir depositional system of Kela 2 gas field is a platform - fan delta - braided river system. The reservoir rocks are medium-fine and extremely fine grained sandstones with high structure maturity and low composition maturity. The pore system structure is featured by medium-small pore, medium-fine throat and medium-low assortment. The reservoir of Kela-2 gas field is characteristic of medium porosity and medium permeability. The pay zone is very thick and its lateral distribution is stable with a good connection of sand body. The overpressure is caused mainly by the strongly tectonic squash activities, and other factors including the later rapid raise and compartment of the high-pressure fluid, the injection of high-pressure fluid into the reservoir.Based on the deliverability tests available, the average binomial deliverability equation is provided applicable for the overall field. The experimental results of rock stress-sensitive tests are employed to analyze the change trend of petrophysical properties against net confining stress, and establish the stress-based average deliverability equation. The results demonstrate the effect of rock deformation on the deliverability is limited to less than 5% in the early period of Kela-2 gas field, indicating the insignificant effect on deliverability of rock deformation.In terms of the well pattern comparisons and development planning optimizations, it is recommended that the producers should be located almost linearly along the structural axis. A total of 9 producers have a stable gas supply volume of 10.76 BCMPY for 17 years. For Kela-2 gas field the total construction investment is estimated at ￥7,697,690,000 RMB with the internal earning rate of 25.02% after taxation, the net present value of ￥7,420,160,000 RMB and the payback period of 5.66 years. The high profits of this field development project are much satisfactory.

高温高压条件下泥质岩变质脱水作用的实验研究

泥质岩是地球上广泛分布的一种表壳沉积岩石，与上地壳平均化学组成接近，是俯冲带沉积物的典型代表。本文以赣北双桥山群泥质板岩为主要研究对象，对泥质岩（KFMASH体系）进行了热力学计算、高压差热（HP－DTA）和榴辉岩相温压条件下变质脱水作用的实验研究。研究结果表明，俯冲沉积物在冷、热俯冲带其变质脱水作用的深度范围分别是95～155 km 和48～84 km。泥质岩经历了一个区域进变质作用过程。该过程可以被分为三个阶段：① 绿泥石变质脱水阶段；② 角闪石、白云母变质脱水阶段；③ 黑云母变质脱水阶段。在各阶段中，随含水矿物的变质脱水作用不断进行，流体被逐渐从体系中释放出来。最后以黑云母的消失为标志，指示了泥质岩体系变质脱水作用的结束。在俯冲带深部温度压力条件下，泥质岩所释放出的流体以富集Cu、Pb、Nd、Ba等流体活动性元素为主要特征。俯冲带沉积物（岩）在进入到俯冲带深部前，受海水浸染而富集Cl，这导致其在俯冲带深部变质脱水过程中，所释放出的流体中富集Cu、Pb、Rb、Sr、Cs、La、Ba、Ce、Pr、Nd、Sm、Eu等微量元素。而未受到海水浸染或浸染程度较弱俯冲带沉积物，在俯冲带变质脱水过程中所释放出的变质流体中，上述微量元素的富集程度则相对较弱。

高温高压下水热体系中黄铁矿-金原电池的腐蚀电化学原位测量研究

水流体-导电性矿物相互作用是自然界中水流体-固体相互作用的重要组成部分，是许多矿床形成和演化的核心过程。迄今为止，绝大多数地质和地球化学家们对导电性矿物在水流体中的溶解机制普遍存在模糊的认识，认为水流体中导电性矿物的溶解和定位是一种简单的化学溶解和沉淀或简单的氧化溶解和还原定位过程，而实质上导电性矿物（组合）在水流体中的溶解是一种由电极电位差驱使下的类似于金属腐蚀的复杂电化学过程。当具有不同电极电位的矿物在溶液中相互接触，就会形成短路原电池发生电化学腐蚀。其中，电极电位低的矿物作为原电池的阳极，其溶解会加剧，而电极电位高的矿物作为原电池的阴极，其溶解会受到抑制。鉴于前人对水流体-导电性矿物相互作用的腐蚀原电池反应机理的模糊认识，本论文工作基于腐蚀原电池观点对高温高压条件下NaCl水流体体系中黄铁矿与金之间的原电池反应进行了研究。 在本工作中，作者与所在的研究小组一道，首先自行研制了一套可用于高温高压水热体系中导电性矿物腐蚀电化学原位测量的高压釜反应装置。该装置主体部件选用在高温高压下具有高强度、抗腐蚀等优良性能的工业纯钛制成。在该装置中，通过将热电偶直接插入高压釜釜腔内，成功地实现了釜内流体温度的准确测量和精确控制。对高压釜不同部位的测温结果表明，沿高压釜的径向与轴向均存在显著的温度梯度，其中釜塞保护锥体处的温度比釜内流体的温度低约8℃，釜外壁中心处与釜内的温度差约10℃；对400℃保温条件下釜内流体温度的直接测量表明，釜内温度波动小于0.5℃。在该装置中，通过将脆性导电性矿物制作成锥形电极，采用耐高温无机绝缘材料制作密封部件，利用锥体自紧式密封技术，成功地解决了脆性电极和电极引线的高压密封与高温绝缘问题；通过引入另一根辅助性的矿物电极引线，成功地解决了原位监测实验过程中矿物电极与引线接触处是否进水的难题，确保了实验的可信度。可行性试验结果表明，该方法不仅可用于高温高压下水流体-导电性矿物，而且可广泛用于水流体-金属间相互作用的腐蚀电化学原位测量研究。 利用上述自行研制的腐蚀电化学实验装置，本工作对高温高压（250-400℃；10-35 MPa）NaCl水流体体系中黄铁矿-自然金原电池的热力学和动力学进行了实验研究。原位测量结果表明： （1）黄铁矿-金原电池的腐蚀电流变化与其开路电压的变化一致； （2）汽-液平衡条件下，黄铁矿-金原电池的开路电压和腐蚀电流在液相中比在汽相中要大； （3）在温度为400 C、压力远离临界点的过热蒸气和超临界区域，压力在实验研究的范围内（10-35 MPa）对黄铁矿-金原电池的开路电压和腐蚀电流均无显著的影响，随压力的增加两者仅略有增大，但当温度压力跨越临界点时，包括温压从汽-液平衡曲线同时进入超临界区以及温度恒定在400 C、压力跨越临界点时，黄铁矿-金原电池的开路电压和腐蚀电流在临界点附近均发生突变。 （4）在本工作中实验的温度、压力和水流体体系条件下，由黄铁矿与金构成的原电池在大多数情况下黄铁矿为阳极，因此在原电池短路时黄铁矿在水流体中发生氧化溶解，而金则为阴极，在原电池短路时金的溶解受到保护，仅在个别狭窄的温度压力范围内情况才相反。 上述原位测量结果与电极表面水流体的性质以及黄铁矿和金的能带结构密切相关，运用混合电位理论、Butler-Volmer方程以及半导体电化学的波动能级模型对实验结果能进行很好的解释。

高温高压下部分熔融岩石和岩石玻璃弹性波速研究

人类对地球深部结构的认识主要依赖于天然地震的观测资料，高温高压下矿物、岩石和岩浆玻璃的弹性波速测量，是对野外地震波探测资料进行物质反演的重要依据，也为建立地球内部结构模型和地球动力学研究提供重要的实验数据。大量研究证实，高温高压下岩石的部分熔融将形成地震波低速层。然而，前人的研究中，多以岩石的纵波波速（Vp）测量结果来讨论区域地壳结构和低速层的成因，而且很少对实验过程中的中间产物进行观察分析。另一方面，由于玻璃在高温高压下具有特殊的弹性性质，一些科学家推测地球内部岩石的非晶质化也将导致地震波低速层形成。但目前这一推测尚缺乏充分的实验数据支持。为此，作者依托YJ-3000吨大腔体高压实验技术平台，利用脉冲反射法和透射－反射法，完成了： （Ⅰ）三江地区花岗岩和角闪斜长片麻岩在最高压力2.0GPa、最高温度1200℃下的纵波波速（Vp）和最高温度600℃下的横波波速（Vs）研究，并通过岩石物态变化过程中的取样实验，综合探讨岩石中矿物脱水、固－固相变、部分熔融对其弹性波速的影响。获得以下主要结论： ① 花岗岩和角闪斜长片麻岩的Vp和Vs随压力及温度的变化趋势基本一致。室温下岩石的Vp和Vs随压力升高而升高，岩石波速具明显的各向异性，而且其各向异性随压力增大到约0.5GPa后逐渐趋于一恒定值； ② 恒定压力下，岩石的Vp和Vs首先随温度升高近线性缓慢降低，当750℃ 950℃后，石英相变完成，岩石的波速由于熔体含量增加又快速降低； ③ 高温高压下岩石的Vp和Vs研究显示了对三江地区地壳结构一致的约束结果，即该区花岗岩主要分布在上地壳，而角闪斜长片麻岩从上地壳底部到中地壳底部均有分布，这一结果与前人利用Vp研究建立的该区地壳模型基本一致； ④ 在三江地区中上地壳高石英含量的岩石中，石英的α－β相变是地壳地震波低速层形成的主要因素，而随岩石中石英含量的变化，高温高压下岩石的部分熔融及岩石的波速各向异性也可能形成低速层。 （Ⅱ）化学成分从基性到酸性的7种岩石的熔体玻璃在1.0GPa和2.0GPa，最高温度1000℃下的Vp研究和最高温度730℃下的Vs研究。获得以下主要结论： ① 与岩石波速随压力增大而增大不同，室温、0.4－2.0GPa压力下，除两种基性岩石（正长辉石岩和粗面玄武岩）的熔体玻璃外，其它5种中酸性岩石的熔体玻璃的Vp均随压力增大而减小，而这7种玻璃的Vs全部随压力增大而减小。而且，玻璃波速随压力增加而异常降低的幅度随样品中SiO2含量的增高逐渐增大； ② 恒定压力下，随实验温度升高，各种玻璃的弹性波速缓慢降低。当温度高于玻璃转变温度Tg后，玻璃弹性波速的温度系数（∂V/∂T）增大约3倍以上； ③ 研究证实了一种新的地震波低速层成因模式，即上地幔岩石中如果含有超过10vol％的玄武岩玻璃，将会形成地震波低速层；假如下地壳基性岩石中中酸性非晶质体含量超过20vol％，也可能导致地壳低速层的形成。

高温高压下花岗闪长质熔体结晶作用的实验研究

岩浆的分离结晶作用是岩浆演化的重要过程，与许多火成岩石的形成密切相关。自二十世纪50年代以来，采用实验手段研究岩浆的形成、演化一直受到地质学家的高度重视。 本文在0.5-2.0GPa、650-750℃和一定水含量条件下，以东准噶尔花岗闪长岩为初始物，进行了花岗闪长质岩浆结晶作用的实验研究。其结果可为东准噶尔地区A型花岗岩的成因提供一定的实验依据。通过对实验产物详细的岩相学观察和电子探针分析，获得以下主要认识： （1）熔体的含水量对矿物开始结晶的温度和晶出矿物的形状、颗粒大小有重要影响。相同时间内熔体含水量高时结晶出的矿物自形程度更好、粒度增大；随着熔体含水量的增加，斜长石的液相线温度降低；保持熔体含水量不变的情况下，随着压力的增加斜长石从熔体中结晶的温度降低。 （2）在压力为0.5GPa、熔体水饱和的条件下，花岗闪长质熔体中斜长石在675℃时开始结晶。结晶的斜长石与原岩的斜长石相比，其成分相对富钠长石而贫钙长石。在温度和熔体水含量一定的条件下，从花岗闪长质熔体中晶出的斜长石随着压力的增加，其钙长石组分增加。 （3）实验产物中的角闪石属于钙角闪石类，具体以普通角闪石为主。与初始花岗闪长岩的角闪石相比，实验产物的角闪石SiO2含量低，Fe3+很少。结晶形成的黑云母为铁叶云母，在2.0GPa压力时没有黑云母晶出而出现多硅白云母。 （4）花岗闪长质熔体发生矿物结晶后的残余熔体的成分受温度、压力和含水量的变化而变化。残余熔体中SiO2含量随着矿物从熔体中结晶程度的增加而升高。与无斜长石结晶的情况相比，有斜长石结晶时残余熔体的SiO2含量要高。在Na2O+K2O-CaO、FeO/(FeO+MgO)分别与SiO2的协变图中，残余熔体成分均落入A型花岗岩区，反映了它们与A型花岗岩在主量元素组成上的近似。因此，本文的实验证明，东准噶尔地区的A型花岗岩浆可以通过花岗闪长质岩浆发生角闪石、黑云母、斜长石的分离结晶作用形成。

库车坳陷异常高压成因与异常高压大气田成藏模式研究

该文从异常压力的成因和分布、异常压力的形成和演化、异常压力对天然气藏形成的作用以及超压带大然气藏形成的主控因素等方面进行研究.在流体力学和热力学研究构造抬升对异常高压的作用、库车坳陷古压力恢复、库车坳陷大气田形成与异常压力演化的关系及库车坳陷高压大气田形成的关键因素等方面取得了创新性成果.

高温高压下地球深部物质弹性波速测量技术研究和应用

岩石、矿物的弹性波速对地球的地震波速度进行物质成分和晶体结构的解释是十分关键的.该次论文工作的目的是在YJ-3000六面顶压机原有弹性波速测量技术的基础上建立一套P波和S波的弹性波速测量的新方法,可以在模拟地球上地幔的高温高压条件下获取物质的弹性参数.通过对超声学的基本概念的引入和超声测量基本技术的分析,特别是超声探头的采用,结合超声测量中透射法和反射法各自的优点,创造性提出了透射-反射联用的新方法.该方法的使用可以达到较高的走时测量精度,避免了温度和压力梯度对高温高压下弹性波波速测量的影响,同时还结束了多年来该压机上不能进行S波波速测量的历史.采用该方法在高压或同时高温高压下对不同的样品进行了弹性波速的测定,测量结果与前人相同样品的数据吻合得较好,表明了这种新方法的可行性和可靠性.

Heterogeneous asymmetric hydrogenation of ethyl pyruvate on chirally modified Pt/Al2O3 catalyst with fixed-bed reactor

The enantioselective hydrogenation of ethyl pyruvate on the cinchonidine modified Pt/Al2O3 catalyst was investigated using a high-pressure reaction system with a fixed-bed reactor for the purpose to produce the,chiral product without separating the catalyst from the reaction system. The reaction was also investigated in a batch reactor for comparison. About 60% e. e. and 90% e. e. were obtained with the fixed-bed reactor and the batch reactor respectively, demonstrating the possibility for the heterogeneous asymmetric hydrogenation in the fixed-bed reactor. Some adsorbed chiral modifier, cinchonidine, can be slowly removed from the surface of Pt/Al2O3 under the continuous flow reaction, as a result, the e, e, values drops with the reaction time in the fixed-bed reactor. The enantio-selectivity is higher in the fixed-bed reactor, but lower in the batch reactor when ethanol was used as solvent than that when acetic acid as solvent. CO was used as molecular probe to characterize the adsorption of cinchonidine an the catalyst surface by IR spectroscopy, A red shift observed in IR spectra of coadsorbed CO with cinchonidine suggests that the cinchonidine adsorption is mainly through the pi -interaction with platinum surface and donating electron to the platinum surface.

Coadsorption of nitric oxide and oxygen on the Ag(110) surface

The coadsorption of NO and O-2 on Ag(110) surface has been studied by X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS) and in situ Raman spectroscopy. The existence of oxygen enhances the adsorption of NO by forming the NOx species, that is, NO2 and NO3, and the NO in turn as a promotor facilitates the cleavage of the dioxygen bond, forming the surface atomic oxygen species having the same spectral characteristics as those produced using oxygen at high pressure. The oxygen species generated by the interaction is composed of two parts. One is produced directly by the decomposition of surface NO-O-2 complex at ca 625 K, which raised an O 1s feature at 530.5 eV and is absent at ca 800 K, while the another with an O 1s binding energy of 529.2 eV emerges at higher temperatures and shows similar properties as the reported gamma-state oxygen which bound tightly on restructured silver surface. The exposure to NO and O-2 causes noticeable changes in the morphology of the Ag(110) surface and the flat terraces superseded by small (ca 0.1 mu m) pits, and particles with typical diameters of a few micrometres were formed at elevated temperatures. (C) 1999 Elsevier Science B.V. All rights reserved.

Novos sistemas terapêuticos nanotecnológicos

Monografia apresentada à Universidade Fernando Pessoa para obtenção do grau Licenciada em Ciências Farmacêuticas

Large Decrease of Fluctuations for Supercooled Water in Hydrophobic Nanoconfinement

Using Monte Carlo simulations we study a coarse­grained model of a water layer confined in a fixed disordered matrix of hydrophobic nanoparticles at different particle concentrations c. For c = 0 we find a 1st order liquid­liquid phase transition (LLPT) ending in one critical point at low pressure P. For c > 0 our simulations are consistent with a LLPT line ending in two critical points at low and high pressure. For c = 25% at high P and low temperature T we find a dramatic decrease of compressibility, thermal expansion coefficient, and specific heat. Surprisingly, the effect is present also for c as low as 2.4%. We conclude that even a small presence of nanoscopic hydrophobes can drastically suppress thermodynamic fluctuations, making the detection of the LLPT more difficult.

Small angle scattering characterisation of micellar systems and templated architectures

The work described in this thesis reports the structural changes induced on micelles under a variety of conditions. The micelles of a liquid crystal film and dilute solutions of micelles were subjected to high pressure CO2 and selected hydrocarbon environments. Using small angle neutron scattering (SANS) techniques the spacing between liquid crystal micelles was measured in-situ. The liquid crystals studied were templated from different surfactants with varying structural characteristics. Micelles of a dilute surfactant solution were also subjected to elevated pressures of varying gas atmospheres. Detailed modelling of the in-situ SANS experiments revealed information of the size and shape of the micelles at a number of different pressures. Also reported in this thesis is the characterisation of mesoporous materials in the confined channels of larger porous materials. Periodic mesoporous organosilicas (PMOs) were synthesised within the channels of anodic alumina membranes (AAM) under different conditions, including drying rates and precursor concentrations. In-situ small angle x-ray scattering (SAXS) and transmission electron microscopy (TEM) was used to determine the pore morphology of the PMO within the AAM channels. PMO materials were also used as templates in the deposition of gold nanoparticles and subsequently used in the synthesis of germanium nanostructures. Polymer thin films were also employed as templates for the directed deposition of gold nanoparticles which were again used as seeds for the production of germanium nanostructures. A supercritical CO2 (sc-CO2) technique was successfully used during the production of the germanium nanostructures.