Mechanism of gel-to-crystallite conversion process in the synthesis of nanocrystalline multinary oxides

Description of gel-to-crystallite conversion process is made towards the synthesis of nanocrystalline titanates and aluminates. Thermodynamic and kinetic factors governing the conversion of a gel to meta-stable and stable nanocrystalline products(s) are discussed. Correlations between these factors and the preparative conditions employed for the syntheses of titanates and aluminates are arrived at.

Visualisation of a 2′-5′ parallel stranded double helix at atomic resolution: crystal structure of cytidylyl-2′,5′-adenosine

X-ray crystallographlc studies on 3′–5′ ollgomers have provided a great deal of information on the stereochemistry and conformational flexibility of nucleic acids and polynucleotides. In contrast, there is very little Information available on 2′–5′ polynucleotides. We have now obtained the crystal structure of Cytidylyl-2′,5′-Adenoslne (C2′p5′A) at atomic resolution to establish the conformational differences between these two classes of polymers. The dlnucleoside phosphate crystallises in the monocllnlc space group C2, with a = 33.912(4)Å, b =16.824(4)Å, c = 12.898(2)Å and 0 = 112.35(1) with two molecules in the asymmetric unit. Spectacularly, the two independent C2′p5′A molecules in the asymmetric unit form right handed miniature parallel stranded double helices with their respective crystallographic two fold (b axis) symmetry mates. Remarkably, the two mini duplexes are almost indistinguishable. The cytosines and adenines form self-pairs with three and two hydrogen bonds respectively. The conformation of the C and A residues about the glycosyl bond is anti same as in the 3′–5′ analog but contrasts the anti and syn geometry of C and A residues in A2′p5′C. The furanose ring conformation is C3′endo, C2′endo mixed puckering as in the C3′p5′A-proflavine complex. A comparison of the backbone torsion angles with other 2′–5′ dinucleoside structures reveals that the major deviations occur in the torsion angles about the C3′–C2′ and C4′-C3′ bonds. A right-handed 2′–5′ parallel stranded double helix having eight base pairs per turn and 45° turn angle between them has been constructed using this dinucleoside phosphate as repeat unit. A discussion on 2′–5′ parallel stranded double helix and its relevance to biological systems is presented.

Chinese immigrants to Finland: A qualitative study of housing, employment, access to health care and child care as sociological dimensions in their settlement process

The Master’s thesis is qualitative research based on interviews of 15 Chinese immigrants to Finland in order to provide a sociological perspective of the migration experience through the eyes of Chinese immigrants in the Finnish social welfare context. This research is mainly focused upon four crucial aspects of life in the settlement process: housing, employment, access to health care and child care. Inspired by Allardt’s theoretical framework ‘Having, Loving and Being’, social relationships and individual satisfaction are examined in the case of Chinese interviewees dealing with the four life aspects. Finland was not perceived as an attractive migration destination for most Chinese interviewees in the beginning. However, with longer residence in Finland, the Finnish social welfare system gradually became a crucial appealing factor in their permanent settlement in Finland. And meanwhile, social responsibility of attending their old parents in China, strong feelings of being isolated in Finland, and insufficient integration into the Finnish society were influential factors for their decision of returning to China. Social relationships with personal friends, migration brokers, schools, employers and family relatives had great influences in the four life aspects of Chinese immigrants in Finland. The social relationship with the Finnish social welfare sector is supportive to Chinese immigrants, but Chinese immigrants do not heavily rely on Finnish social protection. The housing conditions were greatly improved over time while the upward mobility in the Finnish labour market was not significant among Chinese immigrants. All Chinese immigrants were satisfied with their current housing by the time I interviewed them while most of them had subjective feelings of being alienated in the Finnish labour market, which seriously prevented them from integrating into the Finnish society. In general, Chinese immigrants were satisfied with the low cost of accessing the Finnish public health care services and affordable Finnish child day care services and financial subsidies for children from the Finnish social welfare sector. This research also suggests that employment is the central basis in well-being. Support from the Finnish social welfare sector can improve the satisfaction levels among immigrants, especially when it mitigates the effects of low-paid employment. As well, my empirical study of Chinese immigrants in Finland shows that Having (needs for materials), Loving (needs for social relations) and Being (needs for social integration) are all involved in the four concrete aspects (housing, employment, access to health care and child care).

Compensator for constant relative stability in process control systems

Process control systems are designed for a closed-loop peak magnitude of 2dB, which corresponds to a damping coefficient () of 0.5 approximately. With this specified constraint, the designer should choose and/or design the loop components to maintain a constant relative stability. However, the manipulative variable in almost all chemical processes will be the flow rate of a process stream. Since the gains and the time constants of the process will be functions of the manipulative variable, a constant relative stability cannot be maintained. Up to now, this problem has been overcome either by selecting proper control valve flow characteristics or by gain scheduling of controller parameters. Nevertheless, if a wrong control valve selection is made then one has to account for huge loss in controllability or eventually it may lead to an unstable control system. To overcome these problems, a compensator device that can bring back the relative stability of the control system was proposed. This compensator is similar to a dynamic nonlinear controller that has both online and offline information on several factors related to the control system. The design and analysis of the proposed compensator is discussed in this article. Finally, the performance of the compensator is validated by applying it to a two-tank blending process. It has been observed that by using a compensator in the process control system, the relative stability could be brought back to a great extent despite the effects of changes in manipulative flow rate.

Solid State Electrochemical Sensors in Process Control

The basic principles of operation of gas sensors based on solid-state galvanic cells are described. The polarisation of the electrodes can be minimised by the use of point electrodes made of the solid electrolyte, the use of a reference system with chemical potential close to that of the sample system and the use of graded condensed phase reference electrodes. Factors affecting the speed of response of galvanic sensors in equilibrium and non-equilibrium gas mixtures are considered with reference to products of combustion of fossil fuels. An expression for the emf of non-isothermal galvanic sensors and the criterion for the design of temperature compensated reference electrodes for non-isothermal galvanic sensors are briefly outlined. Non-isothermal sensors are useful for the continuous monitoring of concentrations or chemical potentials in reactive systems at high temperatures. Sensors for oxygen, carbon, and alloying elements (Zn and Si) in liquid metals and alloys are discussed. The use of auxiliary electrodes permits the detection of chemical species in the gas phase which are not mobile in the solid electrolyte. Finally, the cause of common errors in galvanic measurements, and tests for correct functioning of galvanic sensors are given. 60 ref.--AA

Strategic Sales Process Adaptation: Relationship Orientation of the Sales Process in a Business-to-Business Context

Although previous research has recognised adaptation as a central aspect in relationships, the adaptation of the sales process to the buying process has not been studied. Furthermore, the linking of relationship orientation as mindset with adaptation as a strategy and forming the means has not been elaborated upon in previous research. Adaptation in the context of relationships has mostly been studied in relationship marketing. In sales and sales management research, adaptation has been studied with reference to personal selling. This study focuses on adaptation of the sales process to strategically match it to the buyer’s mindset and buying process. The purpose of this study is to develop a framework for strategic adaptation of the seller’s sales process to match the buyer’s buying process in a business-to-business context to make sales processes more relationship oriented. In order to arrive at a holistic view of adaptation of the sales process during relationship initiation, both the seller and buyer are included in an extensive case analysed in the study. However, the selected perspective is primarily that of the seller, and the level focused on is that of the sales process. The epistemological perspective adopted is constructivism. The study is a qualitative one applying a retrospective case study, where the main sources of information are in-depth semi-structured interviews with key informants representing the counterparts at the seller and the buyer in the software development and telecommunications industries. The main theoretical contributions of this research involve targeting a new area in the crossroads of relationship marketing, sales and sales management, and buying and purchasing by studying adaptation in a business-to-business context from a new perspective. Primarily, this study contributes to research in sales and sales management with reference to relationship orientation and strategic sales process adaptation. This research fills three research gaps. Firstly, linking the relationship orientation mindset with adaptation as strategy. Secondly, extending adaptation in sales from adaptation in selling to strategic adaptation of the sales process. Thirdly, extending adaptation to include facilitation of adaptation. The approach applied in the study, systematic combining, is characterised by continuously moving back and forth between theory and empirical data. The framework that emerges, in which linking mindset with strategy with mindset and means forms a central aspect, includes three layers: purchasing portfolio, seller-buyer relationship orientation, and strategic sales process adaptation. Linking the three layers enables an analysis of where sales process adaptation can make a contribution. Furthermore, implications for managerial use are demonstrated, for example how sellers can avoid the ‘trap’ of ad-hoc adaptation. This includes involving the company, embracing the buyer’s purchasing portfolio, understanding the current position that the seller has in this portfolio, and possibly educating the buyer about advantages of adopting a relationship-oriented approach.

Income inequality in the process of economic development : An empirical approach

This thesis studies the effect of income inequality on economic growth. This is done by analyzing panel data from several countries with both short and long time dimensions of the data. Two of the chapters study the direct effect of inequality on growth, and one chapter also looks at the possible indirect effect of inequality on growth by assessing the effect of inequality on savings. In Chapter two, the effect of inequality on growth is studied by using a panel of 70 countries and a new EHII2008 inequality measure. Chapter contributes on two problems that panel econometric studies on the economic effect of inequality have recently encountered: the comparability problem associated with the commonly used Deininger and Squire s Gini index, and the problem relating to the estimation of group-related elasticities in panel data. In this study, a simple way to 'bypass' vagueness related to the use of parametric methods to estimate group-related parameters is presented. The idea is to estimate the group-related elasticities implicitly using a set of group-related instrumental variables. The estimation results with new data and method indicate that the relationship between income inequality and growth is likely to be non-linear. Chapter three incorporates the EHII2.1 inequality measure and a panel with annual time series observations from 38 countries to test the existence of long-run equilibrium relation(s) between inequality and the level of GDP. Panel unit root tests indicate that both the logarithmic EHII2.1 inequality measure and the logarithmic GDP per capita series are I(1) nonstationary processes. They are also found to be cointegrated of order one, which implies that there is a long-run equilibrium relation between them. The long-run growth elasticity of inequality is found to be negative in the middle-income and rich economies, but the results for poor economies are inconclusive. In the fourth Chapter, macroeconomic data on nine developed economies spanning across four decades starting from the year 1960 is used to study the effect of the changes in the top income share to national and private savings. The income share of the top 1 % of population is used as proxy for the distribution of income. The effect of inequality on private savings is found to be positive in the Nordic and Central-European countries, but for the Anglo-Saxon countries the direction of the effect (positive vs. negative) remains somewhat ambiguous. Inequality is found to have an effect national savings only in the Nordic countries, where it is positive.

Lipid-amphotericin B complex structure in solution: A possible first step in the aggregation process in cell membranes

The interactions between the polyene antibiotic amphotericin B with dipalmitoylphosphatidylcholine were investigated in vesicles (using circular dichroism) and in chloroform solution (using circular dichroism and IH, I3C, and 31P nuclear magnetic resonance). The results show that amphotericin B readily aggregates in vesicles and that the extent of aggregation depends on the 1ipid:drug concentration ratio. Introduction of sterol molecules into the membrane hastens the process of aggregation of amphotericin B. In chloroform solutions amphotericin B strongly interacts with phospholipid molecules to form a stoichiometric complex. The results suggest that there are interactions between the conjugated heptene stretch of amphotericin B and the methylene groups of lipid acyl chains, while the sugar moiety interacts with the phosphate head group by the formation of a hydrogen bond. A model is proposed for the lipid-amphotericin B complex, in which amphotericin B interacts equally well with the two lipid acyl chains, forming a 1:l complex.

Low-temperature preparation and characterization of phase-pure lanthanide chromates (V) by the citrate gel process

Phase-pure, crystalline lanthanide chromates LnCrO4 (V), where Ln = La, Pr, Nd, Sm, Gd, Dy, Ho, Yb, Lu and Y, have been prepared by the controlled combustion of the corresponding lanthanide biscitrato chromium (III) complexes at comparatively low temperatures. Formation of chromates (V) was confirmed by X-ray diffraction, infrared and electronic spectroscopy. Phase purity of the materials has also been confirmed by X-ray photoelectron spectroscopy.

Plasma diagnostics of the high pressure oxygen-sputtering process

The characteristics of the high pressure oxygen-sputtering plasma in the pressure range 0.8–2.4 mbar have been studied using the Langmuir probe technique. The variation in plasma parameters such as positive ion density, electron density, mean electron energy and floating potential with pressure and temperature has been investigated. It has been observed that the positive ion density increases at high substrate temperatures whereas the negative ion density decreases. The study of the variation in mean electron energy and floating potential also indicated the possibility that the number of negative ions is less when the substrates are at elevated temperatures. Since the negative ions are supposed to cause re-sputtering and make the films off-stoichiometric, the reduction in the negative ion density as observed at elevated substrate temperatures is better suited for depositing stoichiometric YBa2Cu3O7−δ superconducting thin films.