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991.
This paper applies principles and methods from the framework of anticipatory governance to the case of what the National Research Council calls “complex engineered nanomaterials” (CENM). This framework does not aim to generate crystal ball visions or definitive answers, but rather provides guidance for uncovering, understanding, and addressing social, ethical, environmental, and policy issues that stem from emerging technologies. Thus, in anticipation of increased CENM research, CENM products, and their different governance challenges, we aim to lay the groundwork for the anticipatory governance of CENMs by mapping out what—according to the engineers and scientists, we interviewed who are working at the research level of these CENMs—will be the main issues and themes that we need to pay attention to in the near future. The structured interviews focused on three groups of questions: (1) potential and/or actual applications and/or products from the participant’s research; (2) environmental health and safety issues pertaining to both the participant’s research and CENMs generally; and (3) the future of CENMs. Without a foundational understanding to build on, social scientists, policymakers, and regulatory agencies will be at a loss about how to govern CENMs before they are widely implemented in society. 相似文献
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Risto Koivula 《Central European Journal of Chemistry》2010,8(6):1179-1184
Antimony is perhaps the most frequently used doping element of tin dioxide. Although antimony of different oxidation states have been used in the synthesis, the effect of dopant’s valence on ion exchange properties has not been investigated critically. In our study the valence of antimony had clear effects on the metal uptake properties of Sb-doped SnO2 materials. Extremely high Tc uptake (Kd > 100 000 mL g−1) on Sb(III)-doped material was observed in conditions under which Sb(V)-doped material did not show any Tc uptake. However, the Sb(V)-doped material showed good Ni2+ uptake properties (Kd up to 33 000 mL g−1), even at pH values below the material’s point of zero charge (pzc), while the Sb(III)-doped material showed Ni2+ uptake only at pH above its pzc. The cation uptake of Sb-doped SnO2 resembles typical weakly acidic cation exchanger character but the uptake of TcO4- does not follow a typical anion exchange pattern. Instead, we propose a sorption process related to redox reactions as the probable Tc uptake process. 相似文献
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Georgi E. Chernev Borislava V. Borisova Lyudmila V. Kabaivanova Isabel M. Salvado 《Central European Journal of Chemistry》2010,8(4):870-876
This work reports the sol-gel synthesis of silica hybrids. We determined the effect of the type and quantity of silica precursors and organic compounds on the resulting structure, surface area, nanostructure design and size, and potential applications. The structure of the synthesized hybrids was analyzed using FT-IR, XRD, BET-Analysis, SEM, and AFM. We demonstrate the immovilization of whole living thermophilic bacterial cells with cyanocompound degradation activity in the synthesized silica hybrid biomaterials by entrapment, chemical binding, and adsorption. 相似文献
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I. V. Ukrainets N. L. Bereznyakova Liu Yangyang A. V. Turov 《Chemistry of Heterocyclic Compounds》2010,46(4):452-456
NMR spectroscopy showed that treatment of 1-allyl-3-[(arylamino)methylene]quinoline-2,4-(1H,3H)-diones with an equivalent amount of dry bromine in anhydrous acetic acid leads to the formation of 4-aryliminomethyl-2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinolinium bromides. 相似文献
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Do-Gyeong Lee Dae-Young Lee Myeng-Chong Song Jin-Gyeong Cho Myun-Ho Bang Nam-In Baek 《Chemistry of Natural Compounds》2010,46(3):338-339
A new compound, 4-O-(6'-O-p-hydroxybenzoyl-β-D-glucopyranosyl)-cis-p-coumaric acid, was isolated from the fruits of hot pepper (Capsicum annuum L.). The structure of the compound was established on the basis of NMR, FAB-MS, and IR spectroscopic data. 相似文献