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The herbaceous crops that may provide fermentable carbohydrates for production of fuels and chemicals also contain 10–20% protein. Protein coproduction with biomass-derived fuels and chemicals has important advantages: (1) food and fuel production can be integrated, and (2) protein is a high-value product that may significantly improve overall process economics. We report the results of an integrated approach to producing protein and fermentable sugars from one herbaceous species, Coastal Bermudagrass (CBG). The ammonia fiber explosion (AFEX) process makes possible over 90% conversion of cellulose and hemicellulose to simple sugars (about 650 mg reducing sugars/g dry CBG) at 5 IU cellulase/g vs < 20% conversion for untreated CBG. The AFEX treatment also improves protein extraction from CBG; over 80% protein recovery is possible from AFEX-treated CBG vs about 30% recovery from untreated CBG.  相似文献   
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It is well established that nucleus basalis magnocellularis (NbM) lesions impair performance on tests of sustained attention. Previous work from this laboratory has also demonstrated that pedunculopontine tegmental nucleus (PPTg) lesioned rats make more omissions on a test of sustained attention, suggesting that it might also play a role in mediating this function. However, the results of the PPTg study were open to alternative interpretation. We aimed to resolve this by conducting a detailed analysis of the effects of damage to each brain region in the same sustained attention task used in our previous work. Rats were trained in the task before surgery and post-surgical testing examined performance in response to unpredictable light signals of 1500 ms and 4000 ms duration. Data for PPTg lesioned rats were compared to control rats, and rats with 192 IgG saporin infusions centred on the NbM. In addition to operant data, video data of rats' performance during the task were also analysed.  相似文献   
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Abstract Light is widely thought to move through cells and tissues as rays. Actually light is inherently wave-like; ray motion is a special simple case of wave motion. To determine how well rays simulate light propagation and gradients within cells, absorption and scattering by particles were calculated with two sets of equations: one based on wave propagation within the particle and the other based on ray propagation. The ray model is found to substantially describe absorption at all particle size levels; however, it does not correctly describe scattering. Furthermore, for biological cells and structures larger than λ, the wave equations predict absorption cross sections which are 8–10% larger than expected on the basis of ray optics and extraction data: i.e. absorption is increased by a peculiar wave optics effect. This effect must enhance the efficiency with which the plants collect light energy for photosynthesis. The effect should be accounted for in corrections for the sieve effect.  相似文献   
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Latimer GW  Stetcko EI 《Talanta》1967,14(8):984-988
The Wollack procedure has been used to study the competition between oxidant and acid for the thiosulphate ion. In concentrated hydrochloric acid solutions of iodine, iodate and chloramine-T, polythionates are the chief products, whereas in acid permanganate substantial amounts of other products occur. Both the concentration of the acid and the acid anion affect the course of the reaction in these solutions. Production of polythionate, an acid-decomposition product, suggests that acid decomposition successfully competes with oxidation.  相似文献   
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The technique of ferromagnetic resonance at 23 GHz has been used to determine the first three anisotropy constants of pure Ni down to 4.2K. A temperature and orientation dependent linewidth has also been observed.  相似文献   
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We describe herein formal syntheses of the indole alkaloids cis‐trikentrin A and herbindole B from a common meso‐hydroquinone intermediate prepared by a ruthenium‐catalyzed [2+2+1+1] cycloaddition that has not been used previously in natural product synthesis. Key steps include a sterically demanding Buchwald–Hartwig amination as well as a unique C(sp3)?H amination/indole formation. Studies toward a selective desymmetrization of the meso‐hydroquinone are also reported.  相似文献   
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