223 research outputs found
The Journey from Data to Qualitative Inductive Paper: Who Helps and How?
How do qualitative inductive researchers move from raw data to publishable paper? Existing scholarly resources focus on how to analyze data more deeply and write it up to make a compelling contribution. Much less discussed but also critical is how researchers enlist others in the journey from data to paper – even when they are single authors of their work. Our chapter uncovers qualitative researchers’ helpers and the types of help they provide. Drawing on data from detailed accounts of single authored qualitative, inductive studies, we explain the role of qualitative and quantitative scholars, peers and hired professionals, field informants and journal editors. We talk about help with theorizing, paper structure, emotional support, efficiency enhancement, and process guidance, and we offer practical tips for seeking these different forms of help throughout the research journey
Forces between Colloidal Particles in Aqueous Solutions Containing Monovalent and Multivalent Ions
The present article provides an overview of the recent progress in the direct
force measurements between individual pairs of colloidal particles in aqueous
salt solutions. Results obtained by two different techniques are being
highlighted, namely with the atomic force microscope (AFM) and optical
tweezers. One finds that the classical theory of Derjaguin, Landau, Verwey, and
Overbeek (DLVO) represents an accurate description of the force profiles even
in the presence of multivalent ions, typically down to distances of few
nanometers. However, the corresponding Hamaker constants and diffuse layer
potentials must be extracted from the force profiles. At low salt
concentrations, double layer forces remain repulsive and may become long
ranged. At short distances, additional short range non-DLVO interactions may
become important. Such an interaction is particularly relevant in the presence
of multivalent counterions.Comment: Submitted on 30th of May 2016 as invited article to Curr. Opinion
Colloid Interf. Sci. Edited by W. Ducker and P. Claesson. 15 Pages, 7 Figures
82 reference
Interactions between Silica Particles in the Presence of Multivalent Coions
Forces between charged silica particles in solutions of multivalent coions
are measured with colloidal probe technique based on atomic force microscopy.
The concentration of 1:z electrolytes is systematically varied to understand
the behavior of electrostatic interactions and double-layer properties in these
systems. Although the coions are multivalent the Derjaguin, Landau, Verwey, and
Overbeek (DLVO) theory perfectly describes the measured force profiles. The
diffuse-layer potentials and regulation properties are extracted from the
forces profiles by using the DLVO theory. The dependencies of the diffuse-layer
potential and regulation parameter shift to lower concentration with increasing
coion valence when plotted as a function of concentration of 1:z salt.
Interestingly, these profiles collapse to a master curve if plotted as a
function of monovalent counterion concentration
Remnants of Empire in the Cold War : How Post-War Repatriation to Japan Occasionally Kept Open the ‘Bamboo Curtain’
Globalization, Localization, and Japanese Studies in the Asia-Pacific Region : Past, Present, Future, シドニー大学, 2003年11月10日-13
Forces between Silica Particles in Isopropanol Solutions of 1:1 Electrolytes
Interactions between silica surfaces across isopropanol solutions are
measured with colloidal probe technique based on atomic force microscope. In
particular, the influence of 1:1 electrolytes on the interactions between
silica particles is investigated. A plethora of different forces are found in
these systems. Namely, van der Waals, double-layer, attractive non-DLVO,
repulsive solvation, and damped oscillatory interactions are observed. The
measured decay length of the double-layer repulsion is substantially larger
than Debye lengths calculated from nominal salt concentrations. These
deviations are caused by pronounced ion pairing in alcohol solutions. At
separation below 10 nm, additional attractive and repulsive non-DLVO forces are
observed. The former are possibly caused by charge heterogeneities induced by
strong ion adsorption, whereas the latter originate from structuring of
isopropanol molecules close to the surface. Finally, at increased
concentrations the transition from monotonic to damped oscillatory interactions
is uncovered
Other "Hamlet" in Puppet Theatre: A Contribution to Central European Theatre Diversity of the 1980s-1990s
This study aims to address the stigmatization and reductionism of Central European culture by many scholars and to decentralize it. At the Crossing Borders with Shakespeare Since 1945 conference, the roundtable discussion raised questions about naming and defining “Central Europe” and revealed several discrepancies. However, the discussion lacked cultural, political, and historical context. To address this, the author examines a lesser-known artistic genre, puppet theatre, for answers and comparisons. Zlatko Bourek, a Croatian artist and director, offers a unique perspective on the theatre of the 1980s and serves as an example of the diversity and heterogeneity of Central European cultural expression. Bourek’s work draws from the tradition of Central European puppetry and explores connections between the Iron Curtain and Yugoslavia. His artistic style is exemplified in his adaptation of Tom Stoppard’s play Fifteen-Minute Hamlet, which masterfully condenses the entire plot of William Shakespeare’s Hamlet into a fifteen-minute performance. Bourek’s concept of combining Shakespearean tragedy with farce, presented through Japanese traditional Bunraku theatre, represents an important experiment of the 1980s. The use of syncretism and the aesthetics of ugliness are notable features of this experiment. It is a breakthrough in the perceived history of puppet theatre for adults and an aesthetic experiment in the era of Central European totalitarianism
A Simple Method to Determine Critical Coagulation Concentration from Electrophoretic Mobility
Critical coagulation concentration (CCC) is a key parameter of particle
dispersions, since it provides the threshold limit of electrolyte
concentrations, above which the dispersions are destabilized due to rapid
particle aggregation. A computational method is proposed to predict CCC values
using solely electrophoretic mobility data without the need to measure
aggregation rates of the particles. The model relies on the DLVO theory;
contributions from repulsive double-layer forces and attractive van der Waals
forces are included. Comparison between the calculated and previously reported
experimental CCC data for the same particles shows that the method performs
well in the presence of mono and multivalent electrolytes provided DLVO
interparticle forces are dominant. The method is validated for particles of
various compositions, shapes, and sizes
Formation and relaxation kinetics of starch-particle complexes
© The Royal Society of Chemistry.The formation and relaxation kinetics of starch-particle complexes were investigated in this study. The combination of cationic nanoparticles in suspension and anionic starch in solution gave rise to aggregate formation which was studied by dynamic light scattering, revealing the initial adsorption of the starch molecules on the particle surface. By examining the stability ratio, W, it was found that even in the most destabilized state, i.e. at charge neutralization, the starch chains had induced steric stabilization to the system. At higher particle and starch concentrations relaxation of the aggregates could be seen, as monitored by a decrease in turbidity with time. This relaxation was evaluated by fitting the data to the Kohlrausch-Williams-Watts function. It was found that irrespective of the starch to particle charge ratio the relaxation time was similar. Moreover, a molecular weight dependence on the relaxation time was found, as well as a more pronounced initial aggregated state for the higher molecular weight starch. This initial aggregate state could be due to bridging flocculation. With time, as the starch chains have relaxed into a final conformation on the particle surface, bridging will be less important and is gradually replaced by patches that will cause patchwise flocculation. After an equilibration time no molecular weight dependence on aggregation could be seen, which confirms the patchwise flocculation mechanism
Application of Replica Ornstein-Zernike equations in studies of the adsorption of electrolyte mixtures in disordered matrices of charged particles
The Replica Ornstein-Zernike (ROZ) equations were used to study the adsorption of ions from electrolyte mixtures.
The adsorbent was represented as a quenched primitive model +1:-1 size symmetric electrolyte, while
the mobile particles were ions differing in charge and/or size. The ROZ equations in hypernetted-chain (HNC)
approximation were tested against new Monte Carlo results in the grand canonical ensemble; good agreement
between the two methods was obtained. The ROZ/HNC theory was then used to study the exclusion
coefficients as a function of size and/or charge asymmetry of the annealed ions.Реплiчне рiвняння Орнштейна-Цернiке (РОЦ) застосоване для вивчення адсорбцiї iонiв iз сумiшей
електролiтiв. Адсорбент розглядається у виглядi замороженої примiтивної +1:-1 моделi розмiрно
симетричного електролiту, тодi як рухомi частинки – це iони, що вiдрiзняються зарядом та/або роз-
мiрами. Данi, що отриманi з рiвняння РОЦ у гiперланцюжковому наближеннi (ГЛН), порiвняно з но-
вими результатами Монте-Карло моделювання у великому канонiчному ансамблi i виявлено хороше
узгодження мiж обома методами. Теорiю РОЦ/ГЛН далi було використано для вивчення коефiцiєнтiв
виключення, в залежностi вiд параметрiв розмiрної та/або зарядової асиметрiй нерухомих iонiв
Microstructural analysis of Bulk Molding Compounds and correlation with the flexural strength
In this study, the influence of the glass fiber (GF) content on the
microstructure and flexural strength of bulk molding compounds (BMCs) is
investigated. Three sets of BMCs with different weight fractions of GF
(5/10/12.5 wt%) were commercially prepared and compression molded into test
specimens. The microstructure of the composites was analysed by scanning
electron microscopy and further quantitatively characterized by Voronoi analysis
in order to define the degree of the fiber distribution homogeneity. The
experimental results were compared to the modelled microstructures. The results
revealed that the fiber distribution in the composite with 5 wt% of GF is
considered as the most homogeneous. Through the obtained microstructural
descriptors, the fiber weight content and their distribution were correlated to the
flexural strength of BMCs. The flexural strength was the highest for the
composite with 10 wt% of GF
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