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1.
Aqueous solutions of poly(vinyl pyrrolidone)-fullerene complexes (PVP-C70) have been studied using static and dynamic light scattering methods. Two diffusive processes were detected. The slow diffusion was interpreted as dynamics of large intermolecular PVP-C70 complexes while the fast diffusion was associated with the presence of individual PVP molecules in solution. It was also shown that the molecular weights and dimensions of PVP-C70 complexes are smaller than for PVP-C60 by a factor of 2.5-3. In aqueous solutions of PVP-C70 complex the depolarization and dissymmetry of scattered light were observed in contrast to PVP-C60 solutions. It reveals the existence of anisotropic structures in PVP-C70 solutions. Intermolecular interactions within PVP-C70 complexes are weak and a hydrodynamic field can destroy complexes. 相似文献
2.
Claudio Garibay‐Orijel Elvira Ríos‐Leal Jaime García‐Mena Hctor Mario Poggi‐Varaldo 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(10):1180-1187
A fluidized bed bioreactor (FBBR) was operated for more than 575 days to remove 2,4,6‐trichlorophenol (TCP) and phenol (Phe) from a synthetic toxic wastewater containing 80 mg L?1 of TCP and 20 mg L?1 of Phe under two regimes: Methanogenic (M) and Partially‐Aerated Methanogenic (PAM). The mesophilic, laboratory‐scale FBBR consisted of a glass column (3 L capacity) loaded with 1 L of 1 mm diameter granular activated carbon colonized by an anaerobic consortium. Sucrose (1 g COD L?1) was used as co‐substrate in the two conditions. The hydraulic residence time was kept constant at 1 day. Both conditions showed similar TCP and Phe removal (99.9 + %); nevertheless, in the Methanogenic regime, the accumulation of 4‐chlorophenol (4CP) up to 16 mg L?1 and phenol up to 4 mg L?1 was observed, whereas in PAM conditions 4CP and other intermediates were not detected. The specific methanogenic activity of biomass decreased from 1.01 ± 0.14 in M conditions to 0.19 ± 0.06 mmolCH4 h?1 gTKN?1 in PAM conditions whereas the specific oxygen uptake rate increased from 0.039 ± 0.008 in M conditions to 0.054 ± 0.012 mmolO2 h?1 gTKN?1, which suggested the co‐existence of both methanogenic archaea and aerobic bacteria in the undefined consortium. The advantage of the PAM condition over the M regime is that it provides for the thorough removal of less‐substituted chlorophenols produced by the reductive dehalogenation of TCP rather than the removal of the parent compound itself. Copyright © 2005 Society of Chemical Industry 相似文献
3.
MC Bueno Jayme Gallani RC Rodrigues Colombo E de Araújo Cintra S Brunelli Rigacci 《Canadian Metallurgical Quarterly》1996,4(2):179-199
The overall purpose of this study was to explore nurses' feelings about the applicability and adequacy of a pilot model of nursing assessment (PMNA) developed for coronary care units (CCU) in order to obtain data that could help in establishing a definitive model. The evaluation, performed by 11 CCU nurses, showed that they considered the development and implementation of PMNA as valuable, and that its design was adequate for interviewing cardiac patients. These results will be employed in the elaboration of a definitive model of nursing assessment. 相似文献
4.
Person identification using multiple cues 总被引:6,自引:0,他引:6
Brunelli R. Falavigna D. 《IEEE transactions on pattern analysis and machine intelligence》1995,17(10):955-966
This paper presents a person identification system based on acoustic and visual features. The system is organized as a set of non-homogeneous classifiers whose outputs are integrated after a normalization step. In particular, two classifiers based on acoustic features and three based on visual ones provide data for an integration module whose performance is evaluated. A novel technique for the integration of multiple classifiers at an hybrid rank/measurement level is introduced using HyperBF networks. Two different methods for the rejection of an unknown person are introduced. The performance of the integrated system is shown to be superior to that of the acoustic and visual subsystems. The resulting identification system can be used to log personal access and, with minor modifications, as an identity verification system 相似文献
5.
Emissions of ultrasonic vocalizations (USVs) by rat pups (Rattus norvegicus) during hypothermia have consequences for recovery and warming. The effects on dam behavior of USVs emitted by 3- to 11-day-old pups during hypothermia at rectal temperatures between 18 and 22°C was investigated Rat dams were tested in a Y maze with the home cage as a start box. Dams were given, in one condition, a choice between a hypothermic pup emitting USVs or a hypothermic, silent (anesthetized) pup and, in the other, a choice between 2 hypothermic, silent pups. Although differing in some acoustic properties from normal isolation calls, USVs emitted by hypothermic pups both elicited maternal search behavior and acted as directional cues for dams, in comparisons with control dams exposed only to silent pups. Thus USVs of pups recovering from extreme hypothermia have communicative as well as physiological significance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Elvira B. Rabinovitch 《乙烯基与添加剂工艺杂志》1996,2(1):53-56
It is commonly expected that the heat deflection temperature of finished plastic products will match the values, reported by the material supplier. However, in practice, a significant deviation from the published data is frequently observed. This paper gives insight into the reasons for such a discrepancy. It presents information on the effect of the test variables, such as load, sample conditioning, sample flatness and extrusion conditions, such as: melt temperature and draw-down (internal stresses), on heat deflection temperature of rigid PVC. 相似文献
7.
8.
Decision making with a fuzzy ontology 总被引:2,自引:2,他引:0
Christer Carlsson Matteo Brunelli József Mezei 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(7):1143-1152
Knowledge mobilisation is a transition from the prevailing knowledge management technology that has been widely used in industry for the last 20?years to a new methodology and some innovative methods for knowledge representation, formation and development and for knowledge retrieval and distribution. Knowledge mobilisation aims at coming to terms with some of the problems of knowledge management and at the same time to introduce new theory, new methods and new technology. More precisely, this paper presents an outline of a fuzzy ontology as an enhanced version of classical ontology and demonstrates some advantages for practical decision making. We show that a number of soft computing techniques, e.g. aggregation functions and interval valued fuzzy numbers, will support effective and practical decision making on the basis of the fuzzy ontology. We demonstrate the knowledge mobilisation methods with the construction of a support system for finding the best available wine for a number of wine drinking occasions using a fuzzy wine ontology and fuzzy reasoning methods; the support system has been implemented for a Nokia N900 smart phone. 相似文献
9.
10.
Elvira S. Sandin Julica Folberth Helge Müller-Fielitz Claus U. Pietrzik Elisabeth Herold Thomas E. Willnow Paul T. Pfluger Ruben Nogueiras Vincent Prevot Thomas Krey Markus Schwaninger 《International journal of molecular sciences》2021,22(9)
The mechanisms underlying the transport of leptin into the brain are still largely unclear. While the leptin receptor has been implicated in the transport process, recent evidence has suggested an additional role of LRP2 (megalin). To evaluate the function of LRP2 for leptin transport across the blood-brain barrier (BBB), we developed a novel leptin-luciferase fusion protein (pLG), which stimulated leptin signaling and was transported in an in vitro BBB model based on porcine endothelial cells. The LRP inhibitor RAP did not affect leptin transport, arguing against a role of LRP2. In line with this, the selective deletion of LRP2 in brain endothelial cells and epithelial cells of the choroid plexus did not influence bodyweight, body composition, food intake, or energy expenditure of mice. These findings suggest that LRP2 at the BBB is not involved in the transport of leptin into the brain, nor in the development of obesity as has previously been described. 相似文献