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1.
The performance of reciprocating/rotating scrapers has been assessed in a visualization study of the continuous flow hydrodynamics of air‐fluidized solid biomass under varying conditions of air flow rate and scraping velocities. A combination of low air flow rates and high scraping velocities results in more uniform flow of both types of biomass investigated. Power consumed by the reciprocating action of the scrapers increases with the scraping velocity but typically represents no more than 20% of the overall power consumption at the highest air flow rate applied. We also demonstrate that rotation of the scrapers superimposed on their reciprocating action gives higher flow rate of biomass and better mixing within the bulk solid compared to reciprocating action alone. The application of the reciprocating/rotating scraper technology described in this study represents a viable step forward in developing a continuous, large‐scale process for the microwave‐assisted decomposition of solid biomass to produce bio‐oils. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3732–3738, 2014  相似文献   
2.
Effects of LO-phonon contribution on the electronic and the optical properties are investigated in a Cd0.8Zn0.2Se/ZnSe quantum dot in the presence of magnetic field strength. The magneto-polaron induced hydrogenic binding energy as a function of dot radius in the wide band gap quantum dot is calculated. The oscillator strength and the spontaneous lifetime are studied taking into account the spatial confinement, magnetic field strength and the phonon contribution. Numerical calculations are carried out using variational formulism within the single band effective mass approximation. The optical properties are computed with the compact density matrix method. The magneto-polaron induced optical gain as a function of photon energy is observed. The results show that the optical telecommunication wavelength in the fiber optic communications can be achieved using CdSe/ZnSe semiconductors and it can be tuned with the proper applications of external perturbations.  相似文献   
3.
Different bacterial species and, particularly Pseudomonas fluorescens, can produce gamma-aminobutyric acid (GABA) and express GABA-binding proteins. In this study, we investigated the effect of GABA on the virulence and biofilm formation activity of different strains of P. fluorescens. Exposure of a psychotropic strain of P. fluorescens (MF37) to GABA (10−5 M) increased its necrotic-like activity on eukaryotic (glial) cells, but reduced its apoptotic effect. Conversely, muscimol and bicuculline, the selective agonist and antagonist of eukaryote GABAA receptors, respectively, were ineffective. P. fluorescens MF37 did not produce biosurfactants, and its caseinase, esterase, amylase, hemolytic activity or pyoverdine productions were unchanged. In contrast, the effect of GABA was associated to rearrangements of the lipopolysaccharide (LPS) structure, particularly in the lipid A region. The surface hydrophobicity of MF37 was marginally modified, and GABA reduced its biofilm formation activity on PVC, but not on glass, although the initial adhesion was increased. Five other P. fluorescens strains were studied, and only one, MFP05, a strain isolated from human skin, showed structural differences of biofilm maturation after exposure to GABA. These results reveal that GABA can regulate the LPS structure and cytotoxicity of P. fluorescens, but that this property is specific to some strains.  相似文献   
4.
<正> China further adjusts the tariffs from January1st,2010,mainly related to the MFN(most-favored nation) tax rate,annual provisionaltax rates,the agreement rates,preferentialtax rates and tariff lines.After thisadjustment,China's WTO tariff reductioncommitment has been fully completed.The average import tariff in 2010 is thesame as in 2009,remaining 9.8%.Amongthem,the average tax rate is set at 15.2% foragricultural products,and 8.9% for indus-  相似文献   
5.
Transition metal oxides are capable of a wide range of work functions. This quality allows them to be used in many applications that involve charge transfer with adsorbed molecules, for example as heterogeneous catalysts, as charge‐injection layers in organic electronics, and as electrodes in fuel cells. Chemical and structural factors can alter transition‐metal oxide work functions, often making their work functions difficult to control. Little is known about the effects of the cation oxidation state and point defects on the oxide work function. It is necessary to understand how such chemical and structural factors affect work functions in order to controllably tune transition metal oxides for desired applications. Here, a correlation between the oxide work function and cation oxidation state is demonstrated. This correlation is attributed to the change in cation electronegativity with oxidation state. A model is presented that relates the work function to the oxygen deficiency for d0 oxides in the limit of dilute oxygen vacancies. It is proposed that the rapid initial decrease in work function, observed for d0 oxides, is caused by an increase in the density of donor‐like defect states. It is also shown that oxides tend to have decreased work functions near a metal/metal‐oxide interface as a consequence of the relationship between defects and work function. These insights provide guidelines for tuning transition metal oxide work functions.  相似文献   
6.
We examined 393 African American married couples assigned to (a) a culturally sensitive version of a widely disseminated relationship enhancement program (CS-PREP); (b) a similar version of the same program that also included a focus on prayer (PFP condition); or (c) an information-only control condition in which couples received a self-help version of the same program. Husbands averaged 40.5 years of age and wives averaged 38.9 years. We found a significant interaction between intervention and time of assessment, reflecting group differences in linear trends for the three conditions, with the two intervention conditions performing better than the control condition, and PFP producing superior outcomes to CS-PREP only for wives at post and marginally better results at 12-month follow-up. Results support continued exploration of the adjunctive use of prayer in the context of relationship enhancement programs where appropriate to make them more culturally sensitive. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
7.
8.
Angiotensin‐converting enzyme inhibitory (ACE‐I) activity as affected by Lactobacillus helveticus strains (881315, 881188, 880474, and 880953), and supplementation with a proteolytic enzyme was studied. Reconstituted skim milk (12% RSM) or whey protein concentrate (4% WPC), with and without Flavourzyme® (0.14% w/w), were fermented with 4 different L. helveticus strains at 37 °C for 0, 4, 8, and 12 h. Proteolytic and in vitro ACE‐I activities, and growth were significantly affected (P < 0.05) by strains, media, and with enzyme supplementation. RSM supported higher growth and produced higher proteolysis and ACE‐I compared to WPC without enzyme supplementation. The strains L. helveticus 881315 and 881188 were able to increase ACE‐I to >80% after 8 h of fermentation when combined with Flavourzyme® in RSM compared to the same strains without enzyme supplementation. Supplementation of media by Flavourzyme® was beneficial in increasing ACE‐I peptides in both media. The best media to release more ACE‐I peptides was RSM with enzyme supplementation. The L. helveticus 881315 outperformed all strains as indicated by highest proteolytic and ACE‐I activities.  相似文献   
9.
The developing views of the purposes of school learning (PSLs) and related achievement among immigrant Chinese preschoolers and their European American (EA) age-mates were examined. Both culture and socioeconomic status (SES) were considered simultaneously, an often neglected research approach to studying Asian children. One hundred and fifty 4-year-olds—50 each of middle-class Chinese (CHM), low-income Chinese (CHL), and EA children—completed 2 story beginnings about school and were also tested for their language and math achievement. Results showed that 4-year-olds held sophisticated PSLs, ranging from intellectual to social and affect benefits. Large cultural and SES differences also emerged. CHM children mentioned more adult expectation and seriousness of learning than EA children who expressed more positive affect for self and compliance with adults. CHL children mentioned fewest PSLs. Achievement scores for oral expression of both immigrant groups were significantly lower than those of EA children despite similar reading and math achievement. Controlling for culture and SES, the authors found that children's articulated intellectual, but not other purposes, uniquely predicted their achievement in all tested domains. Cultural and SES influences on immigrant children are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
<正> China's trade surplus narrowed 30.4% toUS$20.03 billion in August from July'sUS$28.73 billion,according to the reportreleased by the General Administration of Customs of China on September 10th.Exports rose 34.4% year-on-year to  相似文献   
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