The influence of the gas environment on morphology and chemical composition of surfaces micro-machined with a femtosecond laser

We investigated the influence of different gas environments on the fabrication of surfaces, homogeneously covered with equally sized and spaced micro-structures. Two types of structures have been successfully micro-machined with a femtosecond laser on titanium surfaces in various atmospheres. The surface chemistry of samples machined in oxygen and helium shows TiO2, while machining in nitrogen leads to an additional share of TiN. The actual surface structure was found to vary significantly as a function of the gas environment. We found that the ablated particles and their surface triggered two consecutive events: The optical properties of the gas environment became non-isotropic which then led to the pulse intensity being redistributed throughout the cross section of the laser beam. Additionally, the effective intensity was further reduced for TiN surfaces due to TiN's high reflectivity. Thus, the settings for the applied raster-scanning machining method had to be adjusted for each gas environment to produce comparable structures. In contrast to previous studies, where only noble gases were found suitable to produce homogeneous patches, we obtained them in an oxygen environment.

Growth and characterization of $SrBi_{2}Nb_{2}O_{9}$ thin films by pulsed-laser ablation

Polycrystalline films of SrBi2Nb2O9 were grown using pulsed-laser ablation. The ferroelectric properties were achieved by low-temperature deposition followed by a subsequent annealing process. The lower switching voltage was obtained by lowering the thickness, which did not affect the insulating nature of the films. The hysteresis results showed an excellent square-shaped loop with results (P-r=6 mu C/cm(2), E-c=100 kV/cm) in good agreement with earlier reports. The films also exhibited a dielectric constant of 250 and a dissipation factor of 0.02. The transport studies indicated an ohmic behavior, while higher voltages induced a bulk space charge.

Growth and study of antiferroelectric lead zirconate thin films by pulsed laser ablation

Antiferroelectric lead zirconate (PZ) thin films were deposited by pulsed laser ablation on platinum-coated silicon substrates. Films showed a polycrystalline pervoskite structure upon annealing at 650 degrees C for 5-10 min. Dielectric properties were investigated as a function of temperature and frequency. The dielectric constant of PZ films was 220 at 100 kHz with a dissipation factor of 0.03. The electric field induced transformation from the antiferroelectric phase to the ferroelectric phase was observed through the polarization change, using a Sawyer-Tower circuit. The maximum polarization value obtained was 40 mu C/cm(2). The average fields to excite the ferroelectric state, and to reverse to the antiferroelectric state were 71 and 140 kV/cm, respectively. The field induced switching was also observed through double maxima in capacitance-voltage characteristics. Leakage current was studied in terms of current versus time and current versus voltage measurements. A leakage current density of 5x10(-7) A/cm(2) at 3 V, for a film of 0.7 mu m thickness, was noted at room temperature. The trap mechanism was investigated in detail in lead zirconate thin films based upon a space charge limited conduction mechanism. The films showed a backward switching time of less than 90 ns at room temperature.

Resolidification behaviour of laser surface-melted metals and alloys

The solidification behaviour is described of two pure metals (Bi and Ni) and two eutectic alloys (A1-Ge and AI-Cu) under nonequilibrium conditions, in particular the microsecond pulsed laser surface melting. The resolidification behaviour of bismuth shows that epitaxial regrowth is the dominant mechanism. For mixed grain size, regrowth of larger grains dominates the microstructure and can result in the development of texture. In the case of nickel, epitaxial growth has been noted. For lower energy pulse-melted pool, grain refinement takes place, indicating nucleation of fresh nickel grains. The A1-Ge eutectic alloy indicates the nucleation and columnar growth of a metastable monoclinic phase from the melt-substrate interface at a high power density laser irradiation. An equiaxed microstructure containing the same monoclinic phase is obtained at a lower power density laser irradiation. It is shown that the requirement of solution partition acts as a barrier to eutectic regrowth from the substrate. The laser-melted pool of A1-Cu eutectic alloy includes columnar growth of c~-A1 and 0-A12Cu phase followed by the dendritic growth of A12Cu phase with ct-Al forming at the interdendritic space. In addition, a banded microstructure was observed in the resolidified laser-melted pool.

X-ray diffraction of permalloy nanoparticles fabricated by laser ablation in water

Permalloy (NiFeMo) nanoparticles were fabricated by laser ablation of bulk material in water with a UV pulsed laser. Transmission electron microscope images showed that approximately spherical particles about 50 nm in diameter were formed in the ablation process. All diffraction peaks corresponding to the bulk material were present in the nanoparticles. In addition to these peaks several new peaks were observed in the nanoparticles, which were attributed to nickel oxide.

Ion beam processing of oriented CuO films deposited on (100) YSZ by laser ablation

A systematic study of Ar ion implantation in cupric oxide films has been reported. Oriented CuO films were deposited by pulsed excimer laser ablation technique on (1 0 0) YSZ substrates. X-ray diffraction (XRD) spectra showed the highly oriented nature of the deposited CuO films. The films were subjected to ion bombardment for studies of damage formation, Implantations were carried out using 100 keV Arf over a dose range between 5 x 10(12) and 5 x 10(15) ions/cm(2). The as-deposited and ion beam processed samples were characterized by XRD technique and resistance versus temperature (R-T) measurements. The activation energies for electrical conduction were found from In [R] versus 1/T curves. Defects play an important role in the conduction mechanism in the implanted samples. The conductivity of the film increases, and the corresponding activation energy decreases with respect to the dose value.

Determination of beta-turn conformation by laser Raman spectroscopy

To correlate the Raman frequencies of the amide I and III bands to beta-turn structures, three peptides shown to contain beta-turn structure by x-ray diffraction and NMR were examined. The compounds examined were tertiary (formula: see text). The amide I band of these compounds is seen at 1,668, 1,665, and 1,677 cm-1, and the amide III band appears at 1,267, 1,265, and 1,286 cm-1, respectively. Thus, it is concluded that the amide I band for type III beta-turn structure appears in the range between 1,665 and 1,677 cm-1 and the amide III band between 1,265 and 1,286 cm-1.

He II spectra of La, Ce and Yb: Novel features in the valence band region

He II photoelectron spectra of La, Ce and Yb show features which cannot be explained in terms of single electron excitations. It is proposed that these are due to formation of electron-hole paris.

Community Pharmacies and the Needs of Mobile EU Citizens - A study on Finns living in Spain

Migration within the European Union (EU) has increased since the Union was established. Community pharmacies provide open access to health care services and can be the first, most frequently used or even the only contact with a nation s health care system among mobile community residents. In some of the mass-migration areas in Southern Europe, most of the customers may represent mobile citizens of foreign background. This has not always been taken into consideration in the development of community pharmacy services. Mobile patients have been on the EU's health policy agenda, but they have seldom been mentioned in the context of community pharmacies. In most of the EU member states, governments control the specific legislation concerning community pharmacies and there is no harmonised pharmaceutical policy or consistent minimal standards for community pharmacy services in the EU. The aim of this study was to understand medication use, the role of community pharmacies and the symptom mitigation process of mobile community residents. Finns living in Spain were used as an example to examine how community pharmacies in a EU member state meet the needs of mobile community residents. The data were collected by a survey in 2002 (response rate 53%, n= 533) and by five focus group discussions in 2006 (n=30). A large number (70%) of the respondents had moved to Spain for health reasons and suffered from chronic morbidity. Community pharmacies had an important role in the healthcare of mobile community residents and the respondents were mostly satisfied with these services. However, several medication safety risks related to community pharmacy practices were identified: 1) Availability of prescription medicines without prescription (e.g., antibiotics, sleeping pills, Viagra®, asthma medications, cardiovascular medicines, psoriasis medicines and analgesics); 2) Irrational use of medicines (e.g., 41% of antibiotic users had bought their antibiotics without a prescription, and the most common reasons for antibiotic self-medication were symptomatic common colds and sore throats); 3) Language barriers between patients and pharmacy professionals; 4) Lack of medication counselling; 5) Unqualified pharmacy personnel providing pharmacotherapy. A fifth of the respondents reported experiencing problems during pharmacy visits in Spain, and the lack of a common language was the source of most of these problems. The findings of this study indicate that regulations and their enforcement can play a crucial role in actually assuring the rational and safe use of medicines. These results can be used in the development of pharmaceutical and healthcare policies in the EU. It is important to define consistent minimum standards for community pharmacy services in the EU. Then, the increasing number of mobile community residents could access safe and high quality health care services, including community pharmacy services, in every member state within the EU.

Analytical studies of gain optimization in CO2-N2 gasdynamic lasers employing two-dimensional wedge nozzles

An analytical method has been proposed to optimise the small-signaloptical gain of CO2-N2 gasdynamic lasers (gdl) employing two-dimensional (2D) wedge nozzles. Following our earlier work the equations governing the steady, inviscid, quasi-one-dimensional flow in the wedge nozzle of thegdl are reduced to a universal form so that their solutions depend on a single unifying parameter. These equations are solved numerically to obtain similar solutions for the various flow quantities, which variables are subsequently used to optimize the small-signal-gain. The corresponding optimum values like reservoir pressure and temperature and 2D nozzle area ratio also have been predicted and graphed for a wide range of laser gas compositions, with either H2O or He as the catalyst. A large number of graphs are presented which may be used to obtain the optimum values of small signal gain for a wide range of laser compositions without further computations.

Use of narrow-pore filters in He II transfer devices - new results

With the aim of finding simple methods for the fabrication of He II refilling devices, He II flow has been studied through filters made from various fine powders (oxides and metals, grain sizes in the range 0.05–2 μm) by compacting them under pressure. The results obtained for the different states of He II flow, especially in the “breakthrough” and “easy flow” range, are explained by the fountain effect, He II hydrodynamics and the choking effect. According to the results, pressedpowder filters can be classified into three groups with different flow characteristics, of which the “good transfer filters” with a behaviour neatly described by simple theory are suitable for use in He II refilling devices.

A laser flash photolysis study of pivalothiophenone triplets: steric and electronic effects in thione photoreaction kinetics

Upon laser pulse excitation (Aex = 532 nm) into the lowest-lying '(n,a*) band system, pivalothiophenones in benzene solutions give rise to short-lived triplets (Ama: = 325-335 nm, em: = (1 1-15) X lo3 M-' cm-I) with quantitative intersystem crossing efficiencies. The triplet yields decrease slightly (by 10-30%) upon changing A, to 308 nm (Le., upon excitation into S2). Kinetic data are presented for intrinsic triplet lifetimes, self-quenching, and quenching by oxygen, di-tert-butylnitroxy radical, and various reagents capable of interacting with the triplets via energy, electron, or hydrogen-atom transfer and by biradical formation (possibly leading to cycloaddition). The mechanisms of the quenching processes are discussed. Relative to rigid aromatic thiones, namely, xanthione and thiocoumarin, the interaction of pivalothiophenone triplets with most of the quenchers are kinetically inefficient. This is interpreted primarily as a manifestation of the steric crowding at positions a to the thiocarbonyl group.

Recipient v russkom razgovore : o raspredelenii funkcij mezhdu otvetami da, nu i tak

The study investigates actions by recipients in spontaneous Russian conversations by focusing on DA, NU and TAK, when they are used as responses to the main speaker's larger on-going turn. The database for the study consists of some 7 hours of spontaneous conversations. The participants of the conversations come from different parts of Russia. The use of DA, NU and TAK was analyzed by applying the method of ethnomethodological conversation analysis from the point of view of the type of the context, the sequential placement of the response and its manner of production. The particles were analyzed both in contexts in which they responded to an informing and in affective contexts. The particles NU and TAK were used by the speakers almost exclusively in informing contexts, whereas DA was the central response type in affective contexts. DA was also the most common response to information with affective implications. The information, to which the particle NU provided as response, was often unspesific and projected a spesification or explanation by its speaker as the next action. DA and TAK, by contrast, treated the information as one that could be followed and was sufficient in its local context. As a response to parenthetical information NU responded to information that was only loosely connected with the mainline of talk. The particle DA, by contrast, was used as a response to such parenthetical information, which was more crucial for the larger on-going activity. Only NU was used as a response that invited the main speaker to continue a turn that she or he had offered as possibly complete. NU was also used by the recipient after her or his own contribution as a continuer. In affective contexts, DA expressed, depending on its more spesific context, not only agreement but also other functions, such as giving up arguing or prior knowledge on the topic being discussed. In addition DA responses were used to display empathy and identification with the state of affairs expressed by the co-participant. NU, by contrast, was seldom used as a response to a turn that expressed affect. When it was used in affective contexts, it displayed agreement with the co-participant or just registered an assessment by her or him.

Proektirovanie perevodčeskih slovarej special'noj leksiki

The methodology of designing normative terminological products has been described in several guides and international standards. However, this methodology is not always applicable to designing translation-oriented terminological products which differ greatly from normative ones in terms of volume, function, and primary target group. This dissertation has three main goals. The first is to revise and enrich the stock of concepts and terms required in the process of designing an LSP dictionary for translators. The second is to detect, classify, and describe the factors which determine the characteristics of an LSP dictionary for translators and affect the process of its compilation. The third goal is to provide recommendations on different aspects of dictionary design. The study is based on an analysis of dictionaries, dictionary reviews, literature on translation-oriented lexicography, material from several dictionary projects, and the results of questionnaires. Thorough analysis of the concept of a dictionary helped us to compile a list of designable characteristics of a dictionary. These characteristics include target group, function, links to other resources, data carrier, list of lemmata, information about the lemmata, composition of other parts of the dictionary, compression of the data, structure of the data, and access structure. The factors which determine the characteristics of a dictionary have been divided into those derived from the needs of the intended users and those reflecting the restrictions of the real world (e.g. characteristics of the data carrier and organizational factors) and attitudes (e.g. traditions and scientific paradigms). The designer of a dictionary is recommended to take the intended users' needs as the starting point and aim at finding the best compromise between the conflicting factors. When designing an LSP dictionary, much depends on the level of knowledge of the intended users about the domain in question as well as their general linguistic competence, LSP competence, and lexicographic competence. This dissertation discusses the needs of LSP translators and the role of the dictionary in the process of translation of an LSP text. It also emphasizes the importance of planning lexicographic products and activities, and addresses many practical aspects of dictionary design.

Literaturnaja skazka A.M. Remizova (1900-1920-e gody)

Literary tale of A.M. Remizov (1900’s – 1920’s) The thesis is devoted to a detailed historical-literary description of a tale as a genre tradition in the creative work of Alexei Mikhailovich Remizov (1877-1957), one of the major Russian prose writers of the 20’s century. This very approach allows to specify the place and functional meaning of this genre in literary practice of the writer and to appeal to one of the key problems of the 20-21 century literature history – a specific of modernistic literature composition principle and a role of montage techniques in its formation. Remizov was working on tales during his whole life, though the most productive years of folklore studies fell to 1900’s – 1910’s. During this period he intensively studied folklore materials, narrated several hundreds of folk tales and in 1900’s – 1920’s published eight tale collections which played a significant role in the formation of stylistic and compositional principles of his prose of the 1910’s – 1920’s, especially montage techniques, which in its turn influenced the development of the narrative forms in the Russian post-revolutionary literature. At the same time a tale has specified not only poetics but also problematics of Remizov’s creative work, as when choosing folklore sources the writer always alluded to modern themes and relevant intellectual trends. The current research work, based on various archive materials and a wide spectrum of modern historical-literary data, complies four chapters with a consistent description of creation history, publication and critics’ reviews of Remizov’s tale collections and single tales contributing to his creative evolution characteristic. Furthermore, the work refers to composition and subject of the particular collections. On the whole it enables to follow up genre dynamics. The first chapter of the work is devoted to Posolon’ (Sunwise), the earliest tale collection of Remizov. The main feature of the collection is that its composition is oriented on the agrarian calendar and the subject – on the system of mythological views reflected in the Russian folklore. This very collection to a large extent corresponds to the writer’s views on the myth represented in Pis’mo v redaktsiyu (Letter to the Editor). The history of this manifesto appearing is analyzed in the second chapter. The incident which caused its forthcoming contributed to ‘legitimization’ of Remizov’s narrations as a relevant genre of modern literature and to upgrading the writer in professional hierarchy. The third chapter analyzes Remizov’s collections of 1900’s – early 1920’s, a result of Remizov’s scrupulous work with a specific tale material. He is acting here as a tale repertory researcher and in some cases as a collector as well. The means of such collections’ topical organization is not the myth but the hero of the tale. According to this principle single pieces are grouped into cycles, which then form complicated montage constructs. Texts themselves can be viewed as a sort of hyper-quotations, as they in fact entirely coincide with their original sources. Besides, collections usually have their own ideal patterns. In the fourth chapter a connection of Remizov’s creative work with folk fun culture and a tradition of the folklore noel story is being demonstrated on Zavetnyie skazy (Secret Tales) material. A consistent collections’ history creation analysis convinces us that the tale was a sort of laboratory in which main writer’s prose methods were being worked out.