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101.
Creasing is one of the most important properties of textiles for apparel application. Most fabrics are regularly evaluated by means of etalons, that is, visual standards. Nevertheless, due to the disadvantages of visual evaluation, which is unreliable and time consuming, several objective methods were developed. In this article, a new objective method of multidirectional evaluation of creasing is described. We have proposed the test method of angle recovery using image processing. The specimen of the fabric was of a circular shape and it was measured by the method of angle recovery in various directions. We compared the results obtained from our method with the method described by Sommer and by the hollow cylinder method also. We found good conformity between the results obtained from our method and the method described by Sommer. 相似文献
102.
Katarina Haugen Einar Holm Magnus Strömgren Bertil Vilhelmson Kerstin Westin 《Papers in Regional Science》2012,91(1):65-84
Drawing on a combination of register data and travel survey data, this research explores changes in the accessibility to different amenities for the Swedish population between 1995 and 2005, as well as the reasons behind the changes: redistribution of either amenities or the population. Overall, proximity has increased concerning most of the amenities during the period. However, despite decreasing ‘potential’ distances, actual travel distances are growing longer due to, for example, an increasing selectivity in preferences. An analysis of the accessibility development for service amenities shows that restructuring within the service sector is the main cause of the changes, and to a lesser extent population redistribution. Resumen. Haciendo uso de una combinación de datos de registros y encuestas de viajes, este estudio explora cambios en la accesibilidad de diferentes servicios y lugares de recreo para la población sueca entre 1995 y 2005, así como las razones detrás de dichos cambios: una redistribución de los servicios o de la población. En conjunto, la proximidad ha aumentado con respecto a la mayoría de los servicios durante el periodo estudiado. Sin embargo, a pesar de las reducciones en distancias “potenciales”, las distancias de viaje están aumentando debido a por ejemplo una mayor selectividad en las preferencias. Un análisis del desarrollo de la accesibilidad de servicios y ocio muestra que la reestructuración dentro del sector servicios es la causa principal de los cambios y, en menor medida, la redistribución de la población. 相似文献
103.
Katarina Ohlsson Tina Bergman Per-Erik Sundell Tomas Deltin Irina Tran Martin Svensson Mats Johansson 《Progress in Organic Coatings》2012
Limitation of volatile organic compound (VOC) emissions has lead to the development of new coil coating systems with reduced solvent content. Reactive diluents derived from vegetable oils have been used to substitute up to 40% of the white spirit. The use of vegetable oil derivatives further reduces the handling of solvents improving the workplace environment and safety, enhances the film properties, and introduces a renewable resource in the final coating. The concept can be described as a melamine crosslinkable alkyd which is formed in parallel to the crosslinking process. 相似文献
104.
Pratibha Magar Oscar Parravicini rka tpnkov Katarina Svr
kov Adriana D. Garro Izabela Jendrzejewska Karel Pauk Jan Hoek Josef Jampílek Ricardo D. Enriz Ale Imramovský 《International journal of molecular sciences》2021,22(17)
A series of 14 target benzyl [2-(arylsulfamoyl)-1-substituted-ethyl]carbamates was prepared by multi-step synthesis and characterized. All the final compounds were tested for their ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in vitro, and the selectivity index (SI) was determined. Except for three compounds, all compounds showed strong preferential inhibition of BChE, and nine compounds were even more active than the clinically used rivastigmine. Benzyl {(2S)-1-[(2-methoxybenzyl)sulfamoyl]-4-methylpentan-2-yl}carbamate (5k), benzyl {(2S)-1-[(4-chlorobenzyl)sulfamoyl]-4-methylpentan-2-yl}carbamate (5j), and benzyl [(2S)-1-(benzylsulfamoyl)-4-methylpentan-2-yl]carbamate (5c) showed the highest BChE inhibition (IC50 = 4.33, 6.57, and 8.52 µM, respectively), indicating that derivatives 5c and 5j had approximately 5-fold higher inhibitory activity against BChE than rivastigmine, and 5k was even 9-fold more effective than rivastigmine. In addition, the selectivity index of 5c and 5j was approx. 10 and that of 5k was even 34. The process of carbamylation and reactivation of BChE was studied for the most active derivatives 5k, 5j. The detailed information about the mode of binding of these compounds to the active site of both BChE and AChE was obtained in a molecular modeling study. In this study, combined techniques (docking, molecular dynamic simulations, and QTAIM (quantum theory of atoms in molecules) calculations) were employed. 相似文献
105.
Mirela Lozic Luka Minarik Anita Racetin Natalija Filipovic Mirna Saraga Babic Katarina Vukojevic 《International journal of molecular sciences》2021,22(17)
We aimed to investigate the spatio-temporal expression of possible CAKUT candidate genes CRKL, AIFM3, and UBASH3A, as well as AIF and BCL2 during human kidney development. Human fetal kidney tissue was stained with antibodies and analyzed by fluorescence microscopy and RT-PCR. Quantification of positive cells was assessed by calculation of area percentage and counting cells in nephron structures. Results showed statistically significant differences in the temporal expression patterns of the examined markers, depending on the investigated developmental stage. Limited but strong expression of CRKL was seen in developing kidneys, with increasing expression up to the period where the majority of nephrons are formed. Results also lead us to conclude that AIFM3 and AIF are important for promoting cell survival, but only AIFM3 is considered a CAKUT candidate gene due to the lack of AIF in nephron developmental structures. Our findings imply great importance of AIFM3 in energy production in nephrogenesis and tubular maturation. UBASH3A raw scores showed greater immunoreactivity in developing structures than mature ones which would point to a meaningful role in nephrogenesis. The fact that mRNA and proteins of CRKL, UBASH3A, and AIFM3 were detected in all phases of kidney development implies their role as renal development control genes. 相似文献
106.
107.
Gel structure phase behavior in micro nanofibrillated cellulose containing in situ precipitated calcium carbonate
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Speciality high‐strength board, packaging grades, and novel cellulose‐based nanocomposites may incorporate microcellulosic nanofibrillated materials (MNFC), although the rheological properties of such strongly water sorbing structures are challenging for processing technologies. This study introduces rheological methods for the evaluation of dewatering and flow behavior of such high consistency furnishes to exemplify the effect of energy input on microfibrillar material (MFC), as produced by a combination of enzymatic pretreatment and increased levels of fluidization. The large number of fibril contact points act to entrap water, held both on the fibril surface as immobilized water and in the interfibril spacing forming the gel structure. Tuning of the rheological and dewatering properties has been enabled by in situ precipitation of calcium carbonate filler (in situ PCC) on the MFC, which results in the production of a more uniform furnish. Such in situ PCC coated MFC fibrils incorporated into furnish were seen to increase dewatering rate over that of the furnish mix without the in situ precipitated filler primarily because of the reduction in total surface area of the fibers and fibrils when the pigment is present on the fibrillary surface. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43486. 相似文献
108.
Mechanical and thermal properties of UV cured mixtures of linear and hyperbranched urethane acrylates 总被引:2,自引:0,他引:2
Enis S. Džunuzović Srba V. Tasić Branislav R. Božić Jasna V. Džunuzović Branko M. Dunjić Katarina B. Jeremić 《Progress in Organic Coatings》2012
The properties of urethane acrylate resin mixtures based on the linear and hyperbranched aliphatic polyesters were examined. Linear polyester was synthesized from neopentil glycol and adipic acid. Hyperbranched polyester of the third generation was synthesized from 2,2-bis(hydroxymethyl)propionic acid and di-trimethylol propane. The modification of 60% of hyperbranched aliphatic polyester OH end groups was carried out with isononanoic acid or with soybean fatty acids. Two hyperbranched urethane acrylates, with the same degree of acrylation, and one linear urethane acrylate were obtained by reaction of appropriate polyester and isophorone diisocyanate and 2-hydroxyethyl acrylate. The influence of added amount of HUA and nature of non-acrylic end groups on the rheological, mechanical and thermal properties of the uncured and UV cured mixtures diluted with 20 wt.% hexanediol diacrylate was examined. The nature of non-acrylic end groups have great effect on the interaction between linear and hyperbranched urethane acrylates, which further has a crucial influence on the examined properties of uncured and UV cured mixture samples. 相似文献
109.
We present a model that considers the spatial aspects of biodiversity in urban planning. Stockholm, the capital of Sweden, is used as a study area. The model comprises three steps of strategic selection: (1) information sources; (2) target biotopes, and (3) presentation strategies adapted to priorities in spatial planning. A classification system based on the interpretation of colour infrared aerial photographs was developed. Established methods for the study of woodland and agricultural landscapes were merged and modified in order to fit the present objectives. Ecologically valuable biotopes were found both in green and built-up areas. The methods developed have been used in the comprehensive planning of Stockholm to designate the core areas and the zones in the surrounding landscape with different demands for spatial planning. The model to support urban planners with context-sensitive planning tools was sufficiently flexible for the adaptation to the conditions of each individual area and the level of detail suited to the planning situation. It also provided information on the effects of fragmentation, creating a platform for meaningful follow-up work. 相似文献
110.
Maria Petersson Julia Hagstrm Katarina Nilsson Mats Stading 《Food Hydrocolloids》2007,21(8):1256-1264
Two separate studies were performed. The first studied release of two different preservatives (lactic acid and calcium propionate) from a biopolymer film to a model food with a water activity of aw=0.95. The second investigated the release of four sugars (fructose, maltose, raffinose and stachyose) with different molecular weights from a biopolymer film to a model food with water activities ranging from 0.85 to 0.95. In both studies, the biopolymer films containing the release components were made from kafirin and placed on the model food, consisting of a gel made of gelatine, sucrose and water with well defined water activity. The amount of preservatives and sugars released from the film to the gel were monitored over time using HPLC at different depths in the model food.The release of preservatives was rapid in both cases, and a gradient of released substances had already formed after 2 h in the model food. The gradients levelled out with time. Calcium propionate had a somewhat faster release than lactic acid.The water activity of the model food had a large impact on the release of sugars. A slow release was observed in the model food with aw=0.85, while a much more rapid release occurred in the model food with aw=0.95. There was a limited diffusion depth in the model food with aw=0.85, probably owing to a limited trial time, while the sugars in the model food with aw=0.95 diffused deeper into the model food until the film was depleted of available sugars. 相似文献