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121.
One goal of the VaNTH Engineering Research Center is to estimate the effects of the “value added” to bioengineering student learning as a result of “How People Learn” (HPL) framework interventions. A necessary step in that process is to assess pedagogical differences in both lecture‐based and HPL‐oriented courses. Data from 28 bioengineering courses, over five semesters, were analyzed using a newly developed HPL Index. This index, developed from the Classroom Interaction Observation portion of the VaNTH Observation System, reports levels of HPL‐inspired pedagogy, traditional pedagogy, and classroom organization within a class using codes for different types of faculty and student interactions assigned by an observer in real time. Results confirm the HPL Index's ability to distinguish pedagogical practices based on HPL principles and pedagogical practices based on traditional, non‐HPL pedagogy. 相似文献
122.
Sergio R. Idelsohn Monica Mier-Torrecilla Norberto Nigro Eugenio Oñate 《Computational Mechanics》2010,46(1):115-124
Heterogeneous incompressible fluid flows with jumps in the viscous properties are solved with the particle finite element
method using continuous and discontinuous pressure fields. We show the importance of using discontinuous pressure fields to
avoid errors in the incompressibility condition near the interface. 相似文献
123.
Piero De Filippis Monica Boscolo Mario Gibellini Paolo Rupena Fulvio Rubessa 《Drug development and industrial pharmacy》1991,17(14):2017-2028
The coprecipitates were prepared by a solvent technique using Eudragit E as carrier and indomethacin as a model drug.
X-Ray diffractometry, differential scanning calorimetry (DSC) and wettability tests were employed to investigate the physical state of the studied formulations. Up to 50% of indomethacin can be dispersed in an amorphous state in Eudragit E.
The influence of the pH on the in vitro release of solid dispersions has been evaluated. Because of the good solubility of Eudragit E at pH 1.2 a fast dissolution rate of the drug was observed while a marked delay was noticed at pH 7.5 where the polymer is only permeable to water. At pH 5.8 the kinetics of drug release can be modulated by the drug/polymer ratio. The dissolution rate of the drug can be increased by decreasing its amount in the coevaporate. 相似文献
X-Ray diffractometry, differential scanning calorimetry (DSC) and wettability tests were employed to investigate the physical state of the studied formulations. Up to 50% of indomethacin can be dispersed in an amorphous state in Eudragit E.
The influence of the pH on the in vitro release of solid dispersions has been evaluated. Because of the good solubility of Eudragit E at pH 1.2 a fast dissolution rate of the drug was observed while a marked delay was noticed at pH 7.5 where the polymer is only permeable to water. At pH 5.8 the kinetics of drug release can be modulated by the drug/polymer ratio. The dissolution rate of the drug can be increased by decreasing its amount in the coevaporate. 相似文献
124.
Giovanni Maria Montuori Monica Fadda Gianpaolo Perrella Elena Mele 《The Structural Design of Tall and Special Buildings》2015,24(15):912-940
This paper provides a first insight on tube configurations based on the hexagonal shape (hexagrid) for tall buildings. The idea is to investigate the mechanical properties of hexagrid to assess their applicability in tall buildings and to compare their potential efficiency to the more popular diagrid systems. For the above purposes, a general homogenization approach has been established for dealing with any structural patterns, and a methodology for characterizing the structural patterns from the mechanical point of view has been developed and specified for hexagrids and diagrids. Then on the basis of a simple stiffness criterion, a design procedure has been proposed and applied to a tall building case study, and several structural solutions (both hexagrids and diagrids) have been designed and assessed by varying the major geometrical parameters of the patterns. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
125.
Angel Uruea Monica Aleman Emanuele Cornagliotti Aashish Sharma Michael Haslinger Loic Tous Richard Russell Joachim John Filip Duerinckx Jozef Szlufcik 《Progress in Photovoltaics: Research and Applications》2016,24(8):1149-1156
We report on the progress of imec's n‐type passivated emitter, rear totally diffused rear junction silicon solar cells. Selective laser doping has been introduced in the flow, allowing the implementation of a shallow diffused front surface field and a reduction of the recombination current in the contact area. Simplifications have been implemented towards a more industrial annealing sequence, by replacing expensive forming gas annealing steps with a belt furnace annealing. By applying these improvements, together with an advanced texturing process and emitter passivation by atomic layer deposition of Al2O3, 22.5% efficient cells (three busbars) have been realized on commercial 156 · 156 mm2 Czochralski‐Si. This result has been independently confirmed by ISE CalLab. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
126.
Degradation of pharmaceutical compound pentoxifylline in water by non-thermal plasma treatment 总被引:2,自引:0,他引:2
Monica Magureanu Daniela Piroi Victor David Vasile I. Parvulescu 《Water research》2010,44(11):3445-5278
The decomposition of a model pharmaceutical compound, pentoxifylline, in aqueous solution was investigated using a dielectric barrier discharge (DBD) in coaxial configuration, operated in pulsed regime, at atmospheric pressure and room temperature. The solution was made to flow as a film over the surface of the inner electrode of the plasma reactor, so the discharge was generated at the gas-liquid interface. Oxygen was introduced with a flow rate of 600 sccm. After 60 min plasma treatment 92.5% removal of pentoxifylline was achieved and the corresponding decomposition yield was 16 g/kWh. It was found that pentoxifylline degradation depended on the initial concentration of the compound, being faster for lower concentrations. Faster decomposition of pentoxifylline could be also achieved by increasing the pulse repetition rate, and implicitly the power introduced in the discharge, however, this had little effect on the decomposition yield. The degradation products were investigated by liquid chromatography-mass spectrometry technique (LC-MS). The evolution of the intermediates during plasma treatment showed a fast increase in the first 30 min, followed by a slower decrease, so that these products are almost completely removed after 120 min treatment time. 相似文献
127.
The inversion of the normal reactivity (umpolung) of aldehydes has been induced via N-heterocyclic carbenes (NHCs) thiazol-2-ylidenes 2a or 3a, generated by simple electrolyses of solutions containing thiazolium salt 2 or 3. Accordingly, 1,4-dicarbonyl compounds have been obtained, in mild conditions and in moderate to very high yields, via 1,4-addition of the Breslow intermediates to the suitable Michael acceptor. The procedure has been performed in classical organic solvents (VOCs) as well as in room temperature ionic liquids (RTILs). The different reactivity of aliphatic aldehydes vs the one of aromatic and heteroaromatic aldehydes has been emphasized. 相似文献
128.
Martin Jarenmark Håkan Carlsson Vladimir M. Trukhan Matti Haukka Sophie E. Canton Monica Walczak Wilfred Fullagar Villy Sundström Ebbe Nordlander 《Inorganic chemistry communications》2010,13(3):334-337
The heterodinuclear complexes [FeZn(L)(CH3CO2)2]+ (L = ICIMP or IPCPMP) are structural models for the dinuclear active sites of plant purple acid phosphatases. They can be systematically synthesized from mononuclear iron complexes and enhance the rate of transesterification of 2-hydroxypropyl p-nitrophenyl phosphate, an assay for the catalytic hydrolysis performed by purple acid phosphatases. 相似文献
129.
Monica Anese Lara Manzocco Enrico Maltini 《European Food Research and Technology》2005,221(3-4):434-438
The mechanisms of volatile release from soluble coffee powders with different roasting degrees were studied. The presence of volatiles in the headspace during coffee humidification was analyzed by gas chromatography. Small amounts of volatiles were observed at low water activities (aw), independently from the roasting degree; as the aw increased headspace volatiles rose and then decreased as the moisture further increased. The changes in aw and volatiles went along with the changes of coffee structure from a free-flowing powder to a sticky viscous fluid. The mechanism of volatiles release was controlled by both kinetic and thermodynamic factors. The former prevailed at low aw in glassy systems; while the latter became important at high aw when, due to increased mobility, equilibrium conditions were approached. Modified state diagrams were used to predict the critical temperature and aw at which structural collapse and volatile release occurred. As far as equilibrium condition was achieved, coffee volatiles were partially re-adsorbed in the liquid phase. 相似文献
130.
Zicarelli F Calabrò S Cutrignelli MI Infascelli F Tudisco R Bovera F Piccolo V 《Journal of the science of food and agriculture》2011,91(7):1213-1221
BACKGROUND: The aim of this trial was to evaluate the replacement of rumen fluid with faeces as inoculum in studying the in vitro fermentation characteristics of diets for ruminants using the in vitro gas production technique. Six iso‐protein diets with different forage/concentrate ratios were incubated with rumen fluid (RI) or faeces (FI) collected from sheep. RESULTS: Most of the fermentation parameters were influenced by diet and inoculum (P < 0.01). With both inocula, organic matter degradability (dOM), cumulative gas production (OMCV) and maximum fermentation rate (Rmax) increased as the amount of concentrate in the diet increased. Rmax was lower with FI vs RI (P < 0.01); dOM was higher with FI vs RI and the diet × inoculum interaction was significant. As expected, with both inocula, Rmax increased as the neutral detergent fibre content of the diet decreased. Significant correlations were obtained using both inocula between OMCV/dOM and gas/volatile fatty acid (VFA), while the correlation VFA/dOM was significant only with FI. The microbial biomass yield calculated by stoichiometric analysis for all diets was higher with FI vs RI. With FI the organic matter used for microbial growth showed an overall decreasing trend as the amount of concentrate in the diet increased. CONCLUSION: The results indicate that both faeces and rumen fluid from sheep have the potential to be used as inoculum for the in vitro gas production technique. Copyright © 2011 Society of Chemical Industry 相似文献