Influences of oxygen partial pressure on structure and related properties of ZrO2 thin films prepared by electron beam evaporation deposition

ZrO2 thin films were prepared by electron beam evaporation at different oxygen partial pressures. The influences of oxygen partial pressure on structure and related properties of ZrO2 thin films were studied. Transmittance, thermal absorption, structure and residual stress of ZrO2 thin films were measured by spectrophotometer, surface thermal lensing technique (STL), X-ray diffraction and optical interferometer, respectively. The results showed that the structure and related properties varied progressively with the increase of oxygen partial pressure. The refractive indices and the packing densities of the thin films decreased when the oxygen partial pressure increased. The tetragonal phase fraction in the thin films decreased gradually as oxygen partial pressure increased. The residual stress of film deposited at base pressure was high compressive stress, the value decreased with the increase of oxygen partial pressure, and the residual stress became tensile with the further increase of oxygen pressure, which was corresponding to the evolution of packing densities and variation of interplanar distances. (c) 2007 Elsevier B.V. All rights reserved.

Influences of CO2 laser annealing on mechanical and laser-induced damage properties of ZrO2 thin films

Zirconium dioxide (ZrO2) thin films were deposited on BK7 glass substrates by the electron beam evaporation method. A continuous wave CO2 laser was used to anneal the ZrO2 thin films to investigate whether beneficial changes could be produced. After annealing at different laser scanning speeds by CO2 laser, weak absorption of the coatings was measured by the surface thermal lensing (STL) technique, and then laser-induced damage threshold (LIDT) was also determined. It was found that the weak absorption decreased first, while the laser scanning speed is below some value, then increased. The LIDT of the ZrO2 coatings decreased greatly when the laser scanning speeds were below some value. A Nomarski microscope was employed to map the damage morphology, and it was found that the damage behavior was defect-initiated both for annealed and as-deposited samples. The influences of post-deposition CO2 laser annealing on the structural and mechanical properties of the films have also been investigated by X-ray diffraction and ZYGO interferometer. It was found that the microstructure of the ZrO2 films did not change. The residual stress in ZrO2 films showed a tendency from tensile to compressive after CO, laser annealing, and the variation quantity of the residual stress increased with decreasing laser scanning speed. The residual stress may be mitigated to some extent at proper treatment parameters. (c) 2007 Elsevier GmbH. All rights reserved.

Influence of SiO2 additional layers on the laser induced damage threshold of Ta2O5 films

A series or Ta2O5 films with different SiO2 additional layers including overcoat, undercoat and interlayer was prepared by electron beam evaporation under the same deposition process. Absorption of samples was measured using the surface thermal lensing (STL) technique. The electric field distributions of the samples were theoretical predicted using thin film design software (TFCalc). The laser induced damage threshold (LIDT) was assessed using an Nd:YAG laser operating at 1064 nm with a pulse length of 12 ns. It was found that SiO2 additional layers resulted in a slight increase of the absorption, whereas they exerted little influence on the microdefects. The electric field distribution among the samples was unchanged by adding an SiO2 overcoat and undercoat, yet was changed by adding an interlayer. SiO2 undercoat. The interlayer improved the LIDT greatly, whereas the SiO2 overcoat had little effect on the LIDT. (C) 2007 Elsevier Ltd. All rights reserved.

Influence of oxygen post-treatment on laser-induced damage of antireflection coatings prepared by electron-beam evaporation and ion beam assisted deposition

Antireflection coatings at the center wavelength of 1053 nm were prepared on BK7 glasses by electron-beam evaporation deposition (EBD) and ion beam assisted deposition (IBAD). Parts of the two kinds of samples were post-treated with oxygen plasma at the environment temperature after deposition. Absorption at 1064 nm was characterized based on surface thermal lensing (STL) technique. The laser-induced damage threshold (LIDT) was measured by a 1064-nm Nd:YAG laser with a pulse width of 38 ps. Leica-DMRXE Microscope was applied to gain damage morphologies of samples. The results revealed that oxygen post-treatment could lower the absorption and increase the damage thresholds for both kinds of as-grown samples. However, the improving effects are not the same. (c) 2008 Elsevier B.V. All rights reserved.

Agyrius watanabeorum Ishikawa, a New Record Genus and Species from China and Vietnam(Hemiptera: Reduviidae)

瓦氏阿猎蝽Agyrius watanabeorum 为日本半翅目学者石川忠2002 年根据采自泰国北部的标本所命 名，其描记较为详细，配有正模的整体黑白照片和部分特征图，但对该种的阳茎结构没有提及。在研 究中国和越南的猎蝽时，我们发现了该种。本文中我们重新描述了瓦氏阿猎蝽，绘制了较详细的整体 图和局部特征图。阿猎蝽属Agyrius Stål, 1863 为中国和越南的新记录属，瓦氏阿猎蝽Agyrius watanabeorum Ishikawa, 2002 为中国和越南的新记录种；其在中国和越南的分布也是该属种最北的分布 记录。

昆虫假死性及建巢行为系列研究

本研究是围绕昆虫的假死行为及建巢相关行为两个方面进行的。首先通过对昆虫假死行为的研究历史和现状的综述，作者提出了假死行为是一种特殊拟态的观点。对长壮蝎蝽Laccotrephes robustus Stål成虫在不同的活动空间下(水体内外)的假死行为以及控制假死行为的关键部位的研究结果表明：(1)水体外假死时长明显高于水体中；(2)蝎蝽在水体内外假死行为的差别是对不同捕食压力的适应，能够提高自身的适合度；(3) 头部不是蝎蝽假死发生所必需的，控制胸部各对足完成假死动作的神经节可能是不同的。胡蜂类昆虫的建巢行为直接关系到其蜂群的发展和存活。平唇原胡蜂Prevespa barthelemy (Buysson)隶属于胡蜂科，是一种社会性昆虫。为研究已建造蜂巢的相关生物学特征，对其越冬后蜂巢进行了解剖观察。结果表明：(1)蜂巢中部较大的巢脾为主要的繁殖区；(2)幼虫和工蜂所占比率最高，占全巢各虫态总数的70%左右；(3)巢中成熟个体,除蜂后外其余全部为雌性工蜂；(4)由于当地气候适宜，越冬期的低温虽使其活动能力下降，但不会引起大量死亡，该胡蜂可以在原巢址内越冬。胡蜂类昆虫雌蜂单母建群的过程可以视为是昆虫社群生活起源的短暂重现，对单母建群行为的研究有助于理解昆虫群居生活的发生和发展。通过对焰马蜂Polistis adustus Birgham单母建群过程的观察，结果表明：(1)第一批工蜂羽化前，雌蜂同时担任蜂王和工蜂的职责；(2)各虫态发育历期卵为5-7 d；幼虫13-15 d；蛹为24-28 d；(3) 单母建群时期是决定未来蜂群发展的重要阶段，也是对马蜂类天敌昆虫进行保护和利用的关键时期。

基于OpenGL的真空机器人三维图形仿真

真空机器人是先进半导体制造行业中不可缺少的重要设备之一。本文介绍了一种并联型真空机器人的运动学模型,以及利用OpenGL和STL格式文件在Visual C++6.0程序界面中实现3D图形仿真的方法,取得了良好的实验效果,为进一步实现上位机实时在线监控奠定了基础。

CAD/RP系统间数据模型的转换方法与发展

分析了当前 CAD和 RP系统间数据模型的各种转换方法，并指明了进一步的发展方向。 STL交换标准的局限和不足已日趋明显，由 CAD模型直接分层得到的 CLI格式将成为与 STL文件并存的一种接口格式。

面向快速成形的复杂曲面重建技术研究

针对快速成形工艺特点，提出了一种基于实物的复杂曲面几何重 建的方法。由此直接生成的快速成形机优化STL接口文件，实现了反求容差与模型网格数的 最佳匹配，避免了由通用软件转换存在的错误和繁复，提高了成形设备的前处理效率，并为 反求工程与快速成形技术的有机集成提供了可靠途径。

快速成型技术中分层算法的研究与进展

根据对零件制造精度和效率的关注程度的不同,开发出了多种分层算法。在同等加工时间的情况下,根据加工精度的不同,将这些分层算法分为等层厚分层算法和适应性分层算法两类。通过对STL模型、原始CAD模型和点云数据的分析,讨论了两类分层算法的研究和发展,然后介绍了斜边分层算法和曲面分层算法等先进分层算法的原理和成果,最后讨论了快速成型分层算法的研究方向和趋势。

Structural analysis of glycans and development of microarrays from Helcobacter pylori cell surface glycome

Helicobacter pylori is a bacterial pathogen that affects more than half of the world’s population with gastro-intestinal diseases and is associated with gastric cancer. The cell surface of H. pylori is decorated with lipopolysaccharides (LPSs) composed of three distinct regions: a variable polysaccharide moiety (O-chain), a structurally conserved core oligosaccharide, and a lipid A region that anchors the LPS to the cell membrane. The O-chain of H. pylori LPS, exhibits unique oligosaccharide structures, such as Lewis (Le) antigens, similar to those present in the gastric mucosa and are involved in interactions with the host. Glucan, heptoglycan, and riban domains are present in the outer core region of some H. pylori LPSs. Amylose-like glycans and mannans are also constituents of some H. pylori strains, possibly co-expressed with LPSs. The complexity of H. pylori LPSs has hampered the establishment of accurate structure-function relationships in interactions with the host, and the design of carbohydrate-based therapeutics, such as vaccines. Carbohydrate microarrays are recent powerful and sensitive tools for studying carbohydrate antigens and, since their emergence, are providing insights into the function of carbohydrates and their involvement in pathogen-host interactions. The major goals of this thesis were the structural analysis of LPSs from H. pylori strains isolated from gastric biopsies of symptomatic Portuguese patients and the construction of a novel pathogen carbohydrate microarray of these LPSs (H. pylori LPS microarray) for interaction studies with proteins. LPSs were extracted from the cell surface of five H. pylori clinical isolates and one NCTC strain (26695) by phenol/water method, fractionated by size exclusion chromatography and analysed by gas chromatography coupled to mass spectrometry. The oligosaccharides released after mild acid treatment of the LPS were analysed by electrospray mass spectrometry. In addition to the conserved core oligosaccharide moieties, structural analyses revealed the presence of type-2 Lex and Ley antigens and N-acetyllactosamine (LacNAc) sequences, typically found in H. pylori strains. Also, the presence of O-6 linked glucose residues, particularly in LPSs from strains 2191 and NCTC 26695, pointed out to the expression of a 6-glucan. Other structural domains, namely ribans, composed of O-2 linked ribofuranose residues were observed in the LPS of most of H. pylori clinical isolates. For the LPS from strain 14382, large amounts of O-3 linked galactose units, pointing to the occurrence of a galactan, a domain recently identified in the LPS of another H. pylori strain. A particular feature to the LPSs from strains 2191 and CI-117 was the detection of large amounts of O-4 linked N-acetylglucosamine (GlcNAc) residues, suggesting the presence of chitin-like glycans, which to our knowledge have not been described for H. pylori strains. For the construction of the H. pylori LPS microarray, the structurally analysed LPSs, as well as LPS-derived oligosaccharide fractions, prepared as neoglycolipid (NGL) probes were noncovalently immobilized onto nitrocellulosecoated glass slides. These were printed together with NGLs of selected sequence defined oligosaccharides, bacterial LPSs and polysaccharides. The H. pylori LPS microarray was probed for recognition with carbohydratebinding proteins (CBPs) of known specificity. These included Le and blood group-related monoclonal antibodies (mAbs), plant lectins, a carbohydratebinding module (CBM) and the mammalian immune receptors DC-SIGN and Dectin-1. The analysis of these CBPs provided new information that complemented the structural analyses and was valuable in the quality control of the constructed microarray. Microarray analysis revealed the occurrence of type-2 Lex and Ley, but not type-1 Lea or Leb antigens, supporting the results obtained in the structural analysis. Furthermore, the H. pylori LPSs were recognised by DC-SIGN, a mammalian lectin known to interact with this bacterium through fucosylated Le epitopes expressed in its LPSs. The -fucose-specific lectin UEA-I, showed restricted binding to probes containing type-2 blood group H sequence and to the LPSs from strains CI-117 and 14382. The presence of H-type-2, as well Htype- 1 in the LPSs from these strains, was confirmed using specific mAbs. Although H-type-1 determinant has been reported for H. pylori LPSs, this is the first report of the presence of H-type-2 determinant. Microarray analysis also revealed that plant lectins known to bind 4-linked GlcNAc chitin oligosaccharide sequences bound H. pylori LPSs. STL, which exhibited restricted and strong binding to 4GlcNAc tri- and pentasaccharides, differentially recognised the LPS from the strain CI-117. The chitin sequences recognised in the LPS could be internal, as no binding was detected to this LPS with WGA, known to be specific for nonreducing terminal of 4GlcNAc sequence. Analyses of the H. pylori LPSs by SDS-PAGE and Western blot with STL provided further evidence for the presence of these novel domains in the O-chain region of this LPS. H. pylori LPS microarray was also applied to analysis of two human sera. The first was from a case infected with H. pylori (H. pylori+ CI-5) and the second was from a non-infected control.The analysis revealed a higher IgG-reactivity towards H. pylori LPSs in the H. pylori+ serum, than the control serum. A specific IgG response was observed to the LPS isolated from the CI-5 strain, which caused the infection. The present thesis has contributed to extension of current knowledge on chemical structures of LPS from H. pylori clinical isolates. Furthermore, the H. pylori LPS microarray constructed enabled the study of interactions with host proteins and showed promise as a tool in serological studies of H. pyloriinfected individuals. Thus, it is anticipated that the use of these complementary approaches may contribute to a better understanding of the molecular complexity of the LPSs and their role in pathogenesis.

Developmental, morphological, and behavioural plasticity in the reproductive strategies of stink bugs and their egg parasitoids

L’environnement façonne la physiologie, la morphologie et le comportement des organismes par l’entremise de processus écologiques et évolutifs complexes et multidimensionnels. Le succès reproducteur des animaux est déterminé par la valeur adaptative d’un phénotype dans un environnement en modification constante selon une échelle temporelle d’une à plusieurs générations. De plus, les phénotypes sont façonnés par l’environnement, ce qui entraine des modifications adaptatives des stratégies de reproduction tout en imposant des contraintes. Dans cette thèse, considérant des punaises et leurs parasitoïdes comme organismes modèles, j’ai investigué comment plusieurs types de plasticité peuvent interagir pour influencer la valeur adaptative, et comment la plasticité des stratégies de reproduction répond à plusieurs composantes des changements environnementaux (qualité de l’hôte, radiation ultraviolette, température, invasion biologique). Premièrement, j’ai comparé la réponse comportementale et de traits d’histoire de vie à la variation de taille corporelle chez le parasitoïde Telenomus podisi Ashmead (Hymenoptera : Platygastridae), démontrant que les normes de réaction des comportements étaient plus souvent positives que celles des traits d’histoires de vie. Ensuite, j’ai démontré que la punaise prédatrice Podisus maculiventris Say (Hemiptera : Pentatomidae) peut contrôler la couleur de ses œufs, et que la pigmentation des œufs protège les embryons du rayonnement ultraviolet; une composante d’une stratégie complexe de ponte qui a évoluée en réponse à une multitude de facteurs environnementaux. Puis, j’ai testé comment le stress thermique affectait la dynamique de la mémoire du parasitoïde Trissolcus basalis (Wollaston) (Hymenoptera : Platygastridae) lors de l’apprentissage de la fiabilité des traces chimiques laissées par son hôte. Ces expériences ont révélé que des températures hautes et basses prévenaient l’oubli, affectant ainsi l’allocation du temps passé par les parasitoïdes dans des agrégats d’hôtes contenant des traces chimiques. J’ai aussi développé un cadre théorique général pour classifier les effets de la température sur l’ensemble des aspects comportementaux des ectothermes, distinguant les contraintes des adaptations. Finalement, j’ai testé l’habileté d’un parasitoïde indigène (T. podisi) à exploiter les œufs d’un nouveau ravageur invasif en agriculture, Halyomorpha halys Stål (Hemiptera : Pentatomidae). Les résultats ont montré que T. podisi attaque les œufs de H. halys, mais qu’il ne peut s’y développer, indiquant que le ravageur invasif s’avère un « piège évolutif » pour ce parasitoïde. Cela pourrait indirectement bénéficier aux espèces indigènes de punaises en agissant comme un puits écologique de ressources (œufs) et de temps pour le parasitoïde. Ces résultats ont des implications importantes sur la réponse des insectes, incluant ceux impliqués dans les programmes de lutte biologique, face aux changements environnementaux.

Obst??culos y dificultades en la evoluci??n de las estructuras conceptuales y espitemol??gicas de los futuros maestros : un estudio de casos sobre el fen??meno de las estaciones

Investigar los obst??culos y dificultades que surgen en la evoluci??n de las estructuras conceptuales y epistemol??gicas de los futuros maestros de la Especialidad de Educaci??n Primaria, dentro de la asignatura de Did??ctica de las Ciencias de la Naturaleza, sobre los movimientos relativos de la Tierra y el Sol con el objeto de cuestionarse, indagar y buscar respuesta a los motivos que justifican que se produzcan las estaciones terrestres. Opta por un enfoque metodol??gico de corte cualitativo e interpretativo. Se realiza sobre un grupo del curso 2001-2002, compuesto por 54 alumnos futuros maestros, 45 chicas y 9 chicos, de edades mayoritariamente comprendidas entre los 20 y 23 a??os. La constituci??n de los grupos se hace de tal manera que el n??mero m??ximo de sujetos no es superior a cinco por grupo. Inicialmente se forman 12 grupos (6 de cuatro y 6 de cinco), posteriormente se segrega un nuevo grupo de 3 sujetos, finalmente se selecciona la mitad de ellos. El criterio seguido para la agrupaci??n es reunir en un mismo grupo a individuos con ideas diferentes para as?? favorecer el contraste. La recogida de informaci??n se lleva a cabo a trav??s de tres tipos de instrumentos, cuestionarios, portafolios e informes escritos de reconstrucci??n y an??lisis. El an??lisis de los resultados finales hace posible la detecci??n de tres modelos de explicaci??n inicial y los obst??culos que se encuentran obstruyen la evoluci??n de los m??todos. Ellos est??n relacionados con las creencias y con los principios ontol??gicos impl??citos de los sujetos estudiados. Algunas dificultades se detectan tambi??n con el uso de im??genes mentales en el espacio y la proyecci??n de la vista en un plano. Otro inconveniente est?? asociado a la tendencia tradicional y con los hechos reconoce que tiene que ser explicado. En t??rminos generales, el dise??o metodol??gico utilizado es un nuevo enfoque en el estudio del sistema de STL (Sol-Tierra-Luna) y del fen??meno de la estacionalidad en particular. Por lo tanto, abre nuevas posibilidades que permitan la realizaci??n de nuevos proyectos en las aulas, asumiendo las dimensiones sociales del aprendizaje y la contemplaci??n de ??ste desde la epistemolog??a escolar.

Analys av förvridning vid hålning av rör : Analysis of metal torsion in rotary piercing

Hålningsprocessen är det inledande bearbetningssteget vid varmvalsning av sömlösa rör. Det är en tvärvalsningsprocess i vilken ett cylindriskt ämne valsas mellan två dubbelkoniska val¬sar över en plugg. Valsarna är snedställda med en viss mat¬ningsvinkel, vilken ger upphov till en axiell drivkraft genom ver¬ket. Hela denna pro¬cess är roterande. Detta i kombination med bl.a. de koniska valsarna leder till en förvrid¬ning av röret, dvs. en tänkt rak linje på det ingå¬ende äm¬net övergår till en spiral efter genomförd valsning. Med föreliggande uppgift är målet att studera förvridningen genom teoretisk och experimen¬tell analys. Syftet med detta är dels att få fördjupad kunskap inom området och dels att ut¬veckla en modell för pre¬diktering av förvridningen.Det experimentella arbetet är utfört på ett stål av typ Ovako 280 (SS2142). Denna mjuka stål¬sort valdes i syfte att undvika värmebehandling innan provberedning. För att visuali¬sera för¬vridningen fräs¬tes ett rakt spår längs det ingående äm¬net och hål borrades mot symmetrilinjen. De praktiska undersökningarna utfördes direkt i den löpande produktionen. Genomförda beräkningar uppvisar en längsgående förvridningsvinkel som stämmer väl över¬ens med uppmätt värde. Detta är dock under antagandet att den tangentiella hastighetskoeffi¬cienten varierar linjärt utmed deformationszonen. För en mer utvecklad modell krävs en nog¬grannare analys av kontakten mellan vals/ämne eller en grundligt genomförd uppmätning av ämnets vinkelhastighet.