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Venkat R. Donuru 《Polymer》2010,51(23):5359-5368
Novel near-Infrared emissive BODIPY polymeric dyes (polymers A and B) were prepared by Sonogashira cross-coupling reaction of 2,6-diiodo BODIPY dyes bearing one and two styryl groups at 3,5 positions (5, 6) with 2,6-diethynyl BODIPY dye, respectively. These polymeric dyes (A and B) display absorption maxima at 697 and 738 nm, and emission maxima at 715 and 760 nm, respectively. These polymeric dyes exhibit significant red shifts in absorption and emission maxima due to their extended π-conjugation systems compared with their BODIPY monomeric dyes. The thin films of polymers A and B display further red shift with emission maxima 764 and 810 nm, respectively. Near-infrared BODIPY copolymeric dye (C) was prepared by Sonogashira polymerization of 2,6-diiodo BODIPY dye bearing two styryl groups with 2,5-diethynyl-3-decylthiophene. For comparison in optical properties, deep-red and red emissive BODIPY copolymeric dyes (D and E) were prepared by Sonogashira polymerization of 2,6-diiodo BODIPY dye bearing monostyryl group and 2,6-diiodo BODIPY dye with 2,5-diethynyl-3-decylthiothene, respectively. These polymers display their absorption maxima at 649 nm and 634 nm, and emission maxima at 694 nm and 669 nm, respectively. All the polymers displayed good thermal stability and solubility in dichloromethane, and their lifetimes ranged from 0.7 to 3.4 ns.  相似文献   
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破损玻璃检测器(GBD)主要用来检测家庭住宅或商业楼宇门窗玻璃的破损情况。GBD也可归类为一种监控设备,用以提高家庭或商业环境的安全性,避免非法进入。GBD既可独立工作,也可与其它防盗设备协同工作,形成一套完整的安全系统。GBD的基本工作原理就是捕获各种声音,并对其进行分析,然后报告玻璃是否破碎。基于这种工作模式,GBD的性能很大程度上取决于声源音质,这对设计人员提出了诸多挑战。  相似文献   
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The lateral flow of gas–powder through a packed bed in a cold model is studied to understand the flow and holdup behaviour of powder in the presence of a cavity, nozzle (tuyere) protrusion, and decreasing gas condition, a system used in the ironmaking blast furnace. Experiments conducted in the current study included a two-dimensional (2D) slot-type packed bed. A previously published mass balance and elutriation velocity concept formed the basis for accurately quantifying the static and dynamic powder holdups. Experiments conducted under different conditions such as powder size and flux, gas flow rate, and packed particle density and size resulted in quantifying the powder holdups. The pressure drop in both horizontal and vertical directions is studied in all two-phase flow experiments. The formation of the static holdup with time in the packed bed is studied. The reproducibility of the experiments was confirmed. The static holdup inside the packed bed at various locations along the vertical direction (i.e., height) is also quantified. The static holdup correlation developed based on experimental data resulted in a 95% confidence interval. Static powder holdup increases with a decrease in the superficial gas velocity, an increase in the size of the powder particle, and powder flux. Dynamic holdup also showed a similar trend.  相似文献   
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Temperature is an important determinant of bacterial growth. While the dependence of bacterial growth on different temperatures has been well studied for many bacterial species, prediction of bacterial growth rate for dynamic temperature changes is relatively unclear. Here, the authors address this issue using a combination of experimental measurements of the growth, at the resolution of 5 min, of Escherichia coli and mathematical models. They measure growth curves at different temperatures and estimate model parameters to predict bacterial growth profiles subject to dynamic temperature changes. They compared these predicted growth profiles for various step‐like temperature changes with experimental measurements using the coefficient of determination and mean square error and based on this comparison, ranked the different growth models, finding that the generalised logistic growth model gave the smallest error. They note that as the maximum specific growth increases the duration of this growth predominantly decreases. These results provide a basis to compute the dependence of the growth rate parameter in biomolecular circuits on dynamic temperatures and may be useful for designing biomolecular circuits that are robust to temperature.Inspec keywords: microorganisms, temperature, environmental factors, mean square error methods, parameter estimationOther keywords: bacterial growth rate, dynamic temperature changes, bacterial species, bacterial growth profiles, generalised logistic growth model, escherichia coli, model parameter estimation, coefficient of determination, mean square error, environmental conditions  相似文献   
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Thrombotic microangiopathy (TMA) in renal transplant recipients is commonly associated with calcineurin inhibitors (CNIs), though several factors such as vascular rejection, viral infections and other drugs may play a contributory role. We report a series of 29 patients with TMA, all of whom were on CNIs. Though plasma exchange (PEx) is widely used to treat TMA, therapeutic guidelines are not well defined. All our patients were treated with PEx and discontinuation of CNIs. Thrombotic microangiopathy was diagnosed at a median of 7 days post-transplant. The mean decrease in Hgb and platelets during TMA was 66% and 64%, respectively, and peak serum creatinine during TMA was 7.4 +/- 2.9 mg%. Mean duration of PEx therapy was 8.5 (range 5-23) days. Recovery of platelet count to 150K/mcL and Hgb to 8-10 g/dL were used as endpoints for PEx. Twenty-three/29 (80%) patients recovered graft function after PEx. Twenty/23 (87%) patients who recovered were placed back on CNl. Nineteen/20 (95%) patients tolerated reinstitution of CNl without recurrence of TMA. In post-transplant TMA, PEx was associated with a graft salvage rate of 80%, reversal of hematological changes can be used as the endpoint for PEx therapy and CNl can be reintroduced without risk of recurrence in the majority of patients.  相似文献   
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Gate induced drain leakage (GIDL) current caused by band-to-band tunneling is studied by Monte Carlo simulation with ballistic least-action trajectory integration. Together with weak inversion and early subthreshold simulation by drift-diffusion formalism, the entire range of the OFF-state drain current can be predicted for technology evaluation. The methodology is demonstrated by a case study for source/drain asymmetry super-halo design.  相似文献   
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This paper reviews the development of first-principles based mathematical models for batteries developed on a framework parallel to computation fluid dynamics (CFD), herein termed computational battery dynamics (CBD). This general-purpose framework makes use of the similarity in the equations governing different battery systems, and has resulted in the development of robust models in a relatively short time. Here we review this framework, in the context of applications to the coupled modeling of the thermal and electrochemical behavior of cells, and to the modeling at three different scales, namely pore-level, cell-level and stack-level. The similarity and differences of our approach with other research groups are exemplified. Significant results from each of these advanced applications of modeling are highlighted with emphasis on the insights that can be gained from a first-principles model. In addition, we also demonstrate the usefulness of a combined experimental-modeling approach in describing cells. The models reviewed here are expected to be useful in predicting the behavior of advanced batteries used in electric vehicles (EVs) and hybrid electric vehicles (HEVs).  相似文献   
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