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991.
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993.
E. L. Moore 《International Journal of Infrared and Millimeter Waves》1989,10(10):1317-1325
A quasioptical isolator has been developed at 285 GHz with insertion loss2 dB and isolation 18 dB over a 1% bandwidth. By improving matching techniques, the device should perform as well over bandwidths up to 5%. This design can be easily modified to make a circulator. 相似文献
994.
D. E. Moore 《Journal of polymer science. Part A, Polymer chemistry》1967,5(10):2665-2679
The polymerization of vinyl stearate in aqueous emulsions with a non-ionic emulsifying agent and potassium peroxydisulfate as initiator has been investigated by use of a dilatometric method to follow the reaction. In general, the reaction kinetics do not follow the pattern established for styrene. Variation of initiator concentration produced latices containing approximately equal numbers of latex particles, even though the rate of reaction was almost directly proportional to the peroxydisulfate concentration. For a given initiator and monomer concentration polymerization occurs very slowly when the monomer is completely solubilized but as the number of micelles is reduced and the number of emulsion droplets increased, the rate increases to an optimum value, whereafter it decreases. A mechanism is proposed by which the sparsely soluble vinyl stearate reacts and redistributes itself into latex particles of a different size range from the micelles and emulsion droplets originally present. 相似文献
995.
An organic self-regulating microfluidic system 总被引:1,自引:0,他引:1
In this paper we present an organic feedback scheme that merges microfluidics and responsive materials to address several limitations of current microfluidic systems. By using in situ fabrication and by taking advantage of microscale phenomena (e.g., laminar flow, short diffusion times), we have demonstrated feedback control of the output pH in a completely organic system. The system autonomously regulates an output stream at pH 7 under a range of input flow conditions. A single responsive hydrogel component performs the functionality of traditional feedback system components. Vertically stacked laminar flow is used to improve the time response of the hydrogel actuator. A star shaped orifice is utilized to improve the flow characteristics of the membrane/orifice valve. By changing the chemistry of the hydrogel component, the system can be altered to regulate flow based on hydrogels sensitive to temperature, light, biological/molecular, and others. 相似文献
996.
997.
M. Borkowski R. C. Moore M. G. Bronikowski Jianfeng Chen O. S. Pokrovsky Yuanxian Xia G. R. Choppin 《Journal of Radioanalytical and Nuclear Chemistry》2001,248(2):467-471
A geochemical model describing the solubility of actinides in underground water at the Waste Isolation Pilot Plant (WIPP) Project is under development. The database for this model consists of standard chemical potentials and Pitzer model parameters for hundreds of species that may be present in the WIPP disposal room. Organic ligands used in separation and decontamination processes may be present in the nuclear wastes placed in the WIPP site and could have a significant impact on mobile actinide concentrations. In this work the 1 and 2 stability constants of NpO2
+, UO2
2+, Am3+ and Th4+ with the oxalate anion have been measured in 0.3–5.0M NaCl media at 25 °C by a solvent extraction technique. For the 1:1 complexation, the values of the stability constants increased in the order: NpO2
+<Am3+<UO2
2+<Th4+, in accordance with the actinide charge density and reflecting the strongly ionic bonding of the complexes. The Pitzer ionic interaction model was used to model the data. Because the data were collected mainly in the high ionic strength region, values of (1) were estimated from these plus literature values. The Pitzer model gives a good representation of the data using three interaction parameters (0), (1), and c. 相似文献
998.
999.
A Self‐Assembled Respiratory Chain that Catalyzes NADH Oxidation by Ubiquinone‐10 Cycling between Complex I and the Alternative Oxidase 下载免费PDF全文
Andrew J. Y. Jones James N. Blaza Hannah R. Bridges Benjamin May Anthony L. Moore Judy Hirst 《Angewandte Chemie (International ed. in English)》2016,55(2):728-731
Complex I is a crucial respiratory enzyme that conserves the energy from NADH oxidation by ubiquinone‐10 (Q10) in proton transport across a membrane. Studies of its energy transduction mechanism are hindered by the extreme hydrophobicity of Q10, and they have so far relied on native membranes with many components or on hydrophilic Q10 analogues that partition into membranes and undergo side reactions. Herein, we present a self‐assembled system without these limitations: proteoliposomes containing mammalian complex I, Q10, and a quinol oxidase (the alternative oxidase, AOX) to recycle Q10H2 to Q10. AOX is present in excess, so complex I is completely rate determining and the Q10 pool is kept oxidized under steady‐state catalysis. The system was used to measure a fully‐defined KM value for Q10. The strategy is suitable for any enzyme with a hydrophobic quinone/quinol substrate, and could be used to characterize hydrophobic inhibitors with potential applications as pharmaceuticals, pesticides, or fungicides. 相似文献