Search results for "SCOPE"
showing 10 items of 2420 documents
Bimodal drop size distributions during the early stages of shear induced coalescence
2005
Drop sizes and drop size distributions were determined by means of an optical shear cell in combination with an optical microscope for the systems polyisobutylene/poly(dimethylsiloxane) (I) and poly(dimethyl-co-methylphenylsiloxane)/poly(dimethylsiloxane) (II) at low concentrations of the suspended phases and at different constant shear rates ranging from 10 to 0.5 s-1 . After pre-shearing the two-phase mixtures (I: 50 s-1; II: 100 s-1) for the purpose of producing small drop radii, the shear rate was abruptly reduced to the preselected value and coalescence was studied as a function of time. In all cases one approaches dead end drop radii, i.e. breakup is absent. The drop size distribution…
Morphology of PEO/PDMS blends during shear: Coexistence of two droplet/matrix structures and additive effects
2005
Abstract The morphologies of blends of polyethyleneoxide (PEO 37) and poly(dimethylsiloxane)s (PDSM), with viscosity ratios, λ , of approximately one (PDMS 230) or 2.8 (PDMS 314, being the component of higher viscosity) and interfacial tensions on the order of 10 mN/m, were investigated at 70 °C as a function of shear rate (up to 10 s −1 ) and of time. For the system PEO 37/PDMS 230 we have also studied the influence of the compatibilizer dimethyl–ethyleneoxide–copolymer (PDMS- co -PEO), which is only reasonably soluble in PEO. To investigate the morphologies we have used an optical shear cell in combination with a light microscope. The most important observation consists in the formation o…
On the Role of Drop Break Up for Coalescence Processes and Morphology Development in Polymer Blends under Shear
2005
Drop sizes and drop-size distributions were determined as a function of time at constant shear rates, γ, by means of an optical shear cell in combination with an optical light microscope after preshearing the samples at high γ. The systems under investigation were PIB 3/PDMS 152 (PIB: polyisobutylene, PDMS: poly(dimethylsiloxane), numbers: average molar masses in kg/mol) and COP 26*/PDMS 48 (COP: poly(dimethyl-co-methylphenylsiloxane), asterisk: apparent molar mass); all measurements refer to 25 °C. Systems and conditions were chosen such that shear rates in the vicinity of the intersection of the coalescence and the break up curves become experimentally accessible. Under these conditi…
Putting information back into biological communication.
2010
At the heart of many debates on communication is the concept of information. There is an intuitive sense in which communication implies the transfer of some kind of information, probably the reason why information is an essential ingredient in most definitions of communication. However, information has also been an endless source of misunderstandings, and recent accounts have proposed that information should be dropped from a formal definition of communication. In this article, we re-evaluate the merits and the internal logic of information-based vs. information-free approaches and conclude that information-free approaches are conceptually incomplete and operationally hindered. Instead, we …
Synthesis of Hierarchically Grown ZnO@NT-WS2 Nanocomposites
2009
A chemically specific and facile method for growth of ZnO nanorods on WS2 nanotubes (NT-WS2) is reported. The modification strategy is based on the chalcophilic affinity of Zn, which serves as an anchor to immobilize ZnO colloids onto the WS2 nanotubes. The surface bound ZnO colloids have been used as a seed to grow ZnO nanorods on WS2 nanotubes. The immobilization of ZnO colloids was monitored by UV−vis spectroscopy and photoluminescence spectroscopy whereas the growth of ZnO nanorods was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
Colonization pattern of primary tomato roots by Pseudomonas fluorescens A6RI characterized by dilution plating, flow cytometry, fluorescence, confoca…
2004
Early colonization of primary tomato roots, grown in vitro, by Pseudomonas fluorescens A6RI, introduced by seed bacterization, was monitored for 7 days in three different root zones (zone A, apex+elongation+young hairy zone; zone B, hairy zone; zone C, old hairy zone+collar). Bacterial quantification was assessed by enumeration of (i) colony forming units (cfu) after dilution plating and of (ii) total bacterial cells by flow cytometry. Bacterial distribution and organization in the root zones were analyzed by fluorescence, confocal and scanning electron microscopy. For all sampling dates and zones, the densities of total bacterial cells were significantly higher than those of the cfu. The k…
Prospective Comparison of Loop Excision under Colposcopic Guidance versus Vitom Guidance.
2012
Background: Aim of the study was to compare the quality of loop excision using a colposcope with results using the VITOM system. Results compared included cervical volume removed, intra- and postoperative complications, and positive resection margins. Methods: A total of 200 patients with histologically confirmed high-grade cervical premalignant lesions, persistent atypical cytological results and/or suspicious colposcopic findings, and cytological and histological discrepancies were included in the study. In transformation zone type 1 (T1) only a superficial cone biopsy was done, in zones type 2 and 3 (T2 and T3) a superficial outside cone biopsy or a deeper inside cone biopsy were done re…
UKIRT Observations of the Impact and Consequences of Comet Shoemaker–Levy 9 on Jupiter☆
1997
The observation of Comet Shoemaker-Levy 9's collision with Jupiter in July of 1994 by the United Kingdom Infrared Telescope (UKIRT) produced spectroscopic data of high quality. Analysis of the data for Impact C has produced the first temperature curve that covers such an event, from the first visibility of the plume above the limb through to the settling down of the ejected gas onto the upper jovian atmosphere. Temperatures derived from methane emission show that 5 min after impact, a plume some 6500 km across was heated to similar to 1400 K. At its maximum spatial extent similar to 12 min after impact, a region of Jupiter's atmosphere similar to 45,000 km west from the impact site of the m…
Citocentrifugación como un método adicional para estudiar celomitos de equinodermos: un enfoque comparativo que combina células vivas, preparaciones …
2021
Abstract Introduction: Echinoderm coelomocytes have traditionally been investigated through a morphological approach using light microscopy, which relies on the idea of constant cell shape as a stable character. However, this can be affected by biotic or abiotic conditions. Objective: To analyze if the consistency in cell morphology offered by the cytocentrifugation method, might be used as a convenient tool to study echinoderm coelomocytes. Methods: Cells of Echinaster (Othilia) brasiliensis (Asteroidea), Holothuria (Holothuria) tubulosa (Holothuroidea), Eucidaris tribuloides, Arbacia lixula, Lytechinus variegatus, and Echinometra lucunter (Echinoidea) were spread on microscope slides by c…
The Idiosincrancies of the European M&A Market
2020
This paper provides a comprehensive descriptive analysis of the European market of mergers and acquisitions (MA 2) method of payment; 3) geographical scope; 4) target’s attitude; 5) bidders’ competition; 6) industry relatedness; 7) public status of the firms involved; and 8) acquirers’ ownership of targets before and after the transaction. Additionally, we identify the similarities and differences of this market with those of the dominant market worldwide, namely the US. Both markets show similar trends in their activity and the occurrence of waves concentrated around economic shocks. However, the European market notably exhibits higher levels of friendly and cash deals.