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101.
Karin Bucher Jens Mende Michael Mehring Martin Jansen 《Fullerenes, Nanotubes and Carbon Nanostructures》2007,15(1):29-42
A new Eu-endohedral fullerene cage, namely, Eu@C72, was synthesized, separated, and a single isomer, Eu@C72-I, has been isolated by multi-step HPLC for the first time and characterized by LDI-TOF mass spectrometry, UV-Vis and EPR spectroscopy. Additionally, a second isomer, Eu@C72-II, has been separated by HPLC and identified by LDI-TOF mass spectrometry. 相似文献
102.
In Scientific Visualization, it is often necessary to represent surfaces with data components attached to them, e.g. cutting
surfaces or isosurfaces in CFD data sets with multiple data components. They can contain a vast number of very small triangles.
To make the interactive visual analysis of large data sets still feasible, surface simplification algorithms are used to reduce
the number of triangles significantly. The order of triangles to be removed iteratively is determined by a priority criterion
taking into account as well geometric properties of the surface as irregularities of the data components attached to it. In
the present paper, different gradient and curvature approximation schemes are described and compared with respect to efficiency,
robustness, and their usefulness as priority criteria in our surface simplification method.
Received: 30 June 1998 / Accepted: 9 July 1999 相似文献
103.
Hassan Sawalha Karin Schroën Remko Boom 《American Institute of Chemical Engineers》2009,55(11):2827-2834
Hollow polylactide microcapsules were prepared by multistage premix membrane emulsification of polylactide/dichloromethane/oil solutions in water (nonsolvent). The effects of the different oils on the morphology, thermal, and mechanical properties of the hollow microcapsules were investigated. All oils resulted in hollow microcapsules with controlled shell thickness of ~60 nm except for eugenol, in which irregular, massive capsules were obtained. The properties of the microcapsules were strongly dependent on the oil used, for example the thermal transition temperatures found for hollow capsules were lower than for solid particles prepared without any oil. The crystallinity and transition temperatures of the capsules prepared with linear alkanes were higher than for cyclic alkanes; terpenes gave the lowest transition temperatures. The shell stiffness, measured with atomic force microscopy, was highly dependent on the oil used. Capsules prepared with dodecane showed higher stiffness (3.3 N m?1) than with limonene (2 N m?1) or cyclohexane (1.4 N m?1). © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
104.
Deborah L. Franke Eugene C. Cole Keith E. Leese Karin K. Foarde Michael A. Berry 《Indoor air》1997,7(1):41-54
Abstract A study was conducted to characterize the indoor environment of a multifloor, multiuse, nonproblem, noncompliant building through long-term monitoring for biological, chemical, and particulate pollutants. The study also assessed the effects of cleaning on indoor air quality by providing a program to monitor baseline levels, providing a rigorous (deep) cleaning of the building, and then continuing to monitor after implementation of a standardized, improved, cleaning program. To assess the effectiveness of the cleaning program, air, surface, and dust data from monitoring prior to the cleaning program were compared with those obtained while the improved housekeeping program was in place. Correlations between pollutants and other environmental factors were studied. The data suggest that the improved cleaning program contributed to indoor air quality through the reduction of airborne dust mass, total volatile organic compounds, and culturable bacteria and fungi. 相似文献
105.
Karin Bohmann 《AI & Society》1989,3(4):323-331
The debate in the Federal Republic of Germany on the estimation of the social compatibility of the consequences of technology as a criterion for the evaluation of technical systems has been going on since the mid seventies. The approach presented discusses the normative structurally transcending perspective of the viability and developmental capacity of society. The question of desirable social development as opposed to the technically possible is raised. A criteria system for evaluating social compatibility of new information and communication technologies including AI is focused on and may serve as a consensus building forum for public technology policy discussion. 相似文献
106.
Fluorescence studies on the interaction between pyrene‐labelled poly(acrylic acid) and cyclodextrins
J Sérgio Seixas de Melo Telma Costa Noémia Oliveira Karin Schillén 《Polymer International》2007,56(7):882-899
The interactions, in aqueous media, between a pyrene‐labelled polyelectrolyte poly(acrylic acid) (PAAMePy) with two different degrees of labelling and β‐ and γ‐cyclodextrins (β‐ and γ‐CD) were studied using absorption and fluorescence (steady‐state and time‐resolved) techniques. In addition to qualitative and quantitative parameters obtained from absorption and steady‐state fluorescence spectra, time‐resolved fluorescence data are presented, allowing additional important observations regarding the nature of the interactions. From the overall data it was possible to conclude that in the case of interaction with γ‐CD the efficient encapsulation of two pyrene units into the cavity of the cyclodextrin molecule leads to a decrease in the number of available free monomers and an increase in the number of preformed ground‐state dimers (GSDs) of pyrene. It was also shown that contrary to the situation in water, where only intramolecular interactions are present, the addition of γ‐CD leads to new interpolymeric interactions. The absence of significant changes is noted when the interactions of PAAMePy polymers take place with β‐CD. The excimer‐to‐monomer fluorescence intensity ratio (IE/IM) was found to increase with the added amount of γ‐CD but not with β‐CD. This increase is justified on the basis of the increase of the GSD contribution. The photophysical behaviour was found to be dependent on the pH of the media, but with the absence of relevant interactions between CD and PAAMePy polymer at alkaline values. Copyright © 2007 Society of Chemical Industry 相似文献
107.
The assessment of potential for suicide among patients with a diagnosis of alcohol dependence has consistently been a dilemma for clinicians. Specifically, a problem for both clinicians and researchers has been determining what risk factors distinguish patients with suicidal ideation from those that are in danger of completed suicide. Identifying what clinicians who specialize in substance abuse view as critical in the assessment and treatment of suicidal patients is a first step in gaining a greater understanding of suicide risk within an alcoholic population. The views of these clinicians are presented and compared with empirical findings on the subject. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
Karin A. Hing 《International Journal of Applied Ceramic Technology》2005,2(3):184-199
Bioceramics have been considered for use as synthetic bone graft substitutes (BGSs) for over 30 years, throughout which there have been two primary areas of research: (i) optimization of the physical pore structure and (ii) formulation of an appropriate bioceramic chemistry. While it is well recognized that both the rate of integration and the final volume of regenerated bone are primarily dependent on the macroporosity, there still seems to be some dispute regarding the optimum "type" of porosity. The rate and quality of bone integration have, in turn, been related to a dependence on pore size, porosity volume fraction, and interconnection size and interconnection density, both as a function of structural permeability and mechano-transduction. Moreover, the role of strut microstructure and pore geometry have been considered with respect to their influence on entrapment and recruitment of growth factors (GFs) in addition to its influence on scaffold mechanics. Deconvoluting the relative affects of these parameters is complicated by the use of both resorbable and nonresorbable bioactive bioceramics, which are believed to mediate bioactivity in the osseous environment through two principal mechanisms: (i) directly through dissolution and release of ionic products in vivo , elevating local concentrations of soluble species that interact directly with local cells or influence cell behavior by their effect on local pH, (ii) indirectly through the influence that surface chemistry will have on protein adsorption, GF entrapment, and subsequent cell attachment and function. This article aims to review some of the recent developments in bioceramic BGSs, with a view to understanding how the various physiochemical parameters may be optimized to promote bone healing. 相似文献
109.
Karin Nuernberg Gerd Nuernberg Klaus Ender Dirk Dannenberger Wiebke Schabbel Sven Grumbach Wolfgang Zupp Hans Steinhart 《European Journal of Lipid Science and Technology》2005,107(10):737-745
The aim of this study was to produce high‐quality meat from lambs under different feeding conditions, as measured by the accumulation of n‐3 fatty acids and conjugated linoleic acids (CLA) in muscle and subcutaneous fat. In total, 13 male crossbred lambs (Black Head×Gotland), each at 24 kg live weight, were divided into two feeding groups. Lambs were kept either on pasture (pasture grazing, n = 6) or in the stable (concentrate feeding, n = 7). The linolenic acid (C18:3n‐3) contained in the grass was absorbed and deposited into the different lipid classes of muscle and subcutaneous fat. The proportion of total n‐3 fatty acids in the different lipids of grazing lambs was significantly (p = 0.05) higher compared to that in concentrate‐fed lambs. The n‐6/n‐3 ratio (mean ± SEM) in muscle of grazing lambs was 1.2 ± 0.09 in contrast to 2.3 ± 0.09 (p = 0.05) of the animals kept in the stable. In subcutaneous fat, this ratio was 0.9 ± 0.2 in lambs kept on pasture versus 3.5 ± 0.2 (p = 0.05) after indoor keeping. The relative concentration of C18:1trans‐11 in total muscle lipids, phospholipids, triacylglycerols and subcutaneous fat was significantly increased by grass feeding compared to concentrate feeding. Significant influences of feeding were shown for saturated fatty acids. In concentrate‐fed lambs, a lower content of saturated fatty acids was detected. The proportion of CLAcis‐9,trans‐11 (1.9 ± 0.2% vs. 1.1 ± 0.1% in muscle, 2.5 ± 0.2% vs. 1.4 ± 0.2% in subcutaneous fat, 0.7 ± 0.04% vs. 0.4 ± 0.04% in phospholipids) in lambs was significantly (p = 0.05) higher after grazing than after concentrate feeding, respectively. 相似文献
110.
The density of single spray-dried granules has been determined with a new method based on atomic force microscopy (AFM). Spherical granules with a well-defined diameter are attached to the AFM cantilever, which acts as a beam-type spring, and the mass of a granule is estimated from the shift in the resonant frequency. The error of the measurements associated with the method was estimated to vary between 1% and 5%, depending on the size and shape of the granule. Density measurements of spray-dried WC–Co granules are presented, and the effect of a polymeric binder and dispersant on the consolidation during drying is discussed. 相似文献