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22.
Diego D. Navarra 《Information Technology for Development》2013,19(2):128-140
The focus of this paper is on e-governance policy initiatives in Jordan as a case study of the architecture of ICT programs and of the global transformation of government. We find that global ICT programs introduce new and universal modes of organising centered on innovation and technology initiatives situated across various boundaries, territories and organisational domains and implemented through a novel mix of policy instruments, international institutions, business interests and techno/managerial concepts. Global ICT programs include the development and use of portals, interactive applications an also other ICT programs which aim at the electronic provision of government's services. We conclude that casting these issues as global ICT programs could cater for a much broader inter-disciplinary significance to guide the policy direction of future e-governance initiatives and to evaluate the extent to which the architecture of global ICT programs can contribute to the ambitious targets set by the Millennium Development Goals. 相似文献
23.
Michael Johnson Chuck Li Brian Rasnow Peter Grandsard Hong Xing Angelica Fields 《Journal of The Association for Laboratory Automation》2002,7(4):62
The push for higher throughput screening coupled with the desire to use smaller volumes of material has sparked the development of new technologies. Caliper Technologies, Corp. (Mountain View, CA) has designed a microfluidics chip with unique properties yet to be fully exploited. The translation from a traditional plate-based assay to a microfluidic chip format has provided insights into assay development, screening data requirements, and the technology itself. Running a screen with this new technology presented challenges in throughput, signal acquisition from slow-conversion enzymes, the provision for a negative control, the translation of a time series into a single data point per compound, reagent adhesion in the channels, and fluid property mismatches. Overcoming these obstacles has resulted in a simple, robust system with significant savings in reagent use. Measures to improve throughput and generalize the system will be discussed. 相似文献
24.
Aura Angelica Popa Eugenia Comăniţă Luminiţ Cianga C. I. Simionescu 《Polymer-Plastics Technology and Engineering》2013,52(9-10):871-884
The paper discusses the synthesis of the N,N,′-azobis(formamidopropionic) acid (AFP), along with some characteristics determined from NMR spectrum, differential thermal analysis, and DSC. The behavior of AFP acid—as well as of its analogue, N,N′-azobis(formamidoacetic) acid (AFA)—has been studied in the reaction with aromatic diamine and with bis(glycol)terephthalate, leading to azopolymers of the azopolyamide, or azopolyester, type. On employing N,N′-bis(β-hydroxyethyl) azobis-formamide (HEAF) as the azo bifunctional compound in the reaction with diphenylmethane diisocyanate, a polyurethane possessing azo groups was obtained. The structure of the azopolymers has been spectroscopically confirmed. 相似文献
25.
Application of photo‐selective films to manipulate wavelength of transmitted radiation and photosynthate composition in red beet (Beta vulgaris var. conditiva Alef.)
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26.
We have investigated new poly-vinylidene fluoride/poly-acrylonitrile (PVdF/PAN) based proton conducting membranes by means of vibrational spectroscopy. We find that a complete phase inversion occurs during the preparation procedure, when the gelling solvents are replaced by an acidic solution, providing the proton conducting property. The uptake of acid is promoted both by the presence of PAN and the ceramic filler, Al2O3. No particular interaction between the polymer matrix and the acidic solution could be detected, supporting the picture of an inert matrix entrapping a liquid component. However, the dissociation degree of the acid is decreased due to the spatial confinement in the membrane. By comparing the dissociation degree and the actual amount of acid in the membrane to the conductivity, we conclude that the limiting factor for the conductivity is the long-range mobility of the protons, which is governed by the morphology of the membrane. 相似文献
27.
Bushman Brad J.; Bonacci Angelica M.; Pedersen William C.; Vasquez Eduardo A.; Miller Norman 《Canadian Metallurgical Quarterly》2005,88(6):969
Ruminating about a provocation increases the likelihood of displaced aggression following a minor annoyance (trigger). In Study 1, provoked participants who ruminated for 25 min were more aggressive toward a fumbling confederate than were distracted participants. Provocation-induced negative affect was positively related to aggression but only among those who ruminated. Study 2 conceptually replicated Study 1 and also found that the more negatively people reacted to the trigger, the more likely the trigger was to increase displaced aggression. Study 3 replicated the findings of Studies 1 and 2 by using an 8-hr rumination period. All 3 studies suggest that ruminating about a provocation increases the likelihood that a minor triggering annoyance will increase displaced aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
A series of composites based on polydimethylsiloxane‐α,ω‐diol (PDMS) as polymeric matrix, silica aerogel as reinforcing filler, and the lignin powder—a biomass derivative, as bulking filler, have been prepared. Different weight ratios between components were used. The composites were investigated by scanning electron microscopy, dynamic mechanical analysis, tensile strength tests, X‐ray diffraction analysis, thermogravimetric analysis, and differential scanning calorimetry. The results were compared with those obtained on a reference sample prepared by using a classical material—diatomite and a pure crosslinked PDMS. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
29.
Shanti Kiran Nayak Angelica D. Benavidez Fernando H. Garzon 《Journal of the American Ceramic Society》2019,102(6):3738-3744
Molybdenum carbide has immense potential as an active catalyst for reaction systems such as synthesis of important chemicals like ammonia. However, the carbide is not used as a commercial catalyst or support as the current synthesis processes produce low surface area material or have contaminants such as excess carbon and surface and chemisorbed oxygen. Moreover, attempts to refine the synthesis pathways are usually not supported by any thermochemical modeling. In this study, a facile and reproducible method to synthesize high surface area molybdenum carbide was developed with the help of thermochemical modeling to better understand molybdenum-carbon phase behavior. We have synthesized 2-5 nm particles of MoxC with surface areas of up to 360 m2/g as characterized using a variety of techniques including X-ray diffraction and electron microscopy. 相似文献
30.
Cardenas Angelica Moreno Nakamura Pinto Miguel Kiyoshy Pietrosemoli Ermanno Zennaro Marco Rainone Marco Manzoni Pietro 《Mobile Networks and Applications》2020,25(3):961-968
Mobile Networks and Applications - In this paper we describe a low-cost and low-power consumption messaging system based on LoRa technology. More that one billion people worldwide cannot access... 相似文献