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81.
An array of coupled cavities, each of which contains a triangle-down-level atom, is investigated. An effective Hamiltonian can be achieved under the strong classical driving. We can control the transition between Mott-insulator and superfluid states by the classical driving. The frequency conversion in one site has the same effects of nonlinear in BH hamiltonian which can induce insulator-superfluid states.  相似文献   
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A palladium‐catalyzed direct C‐arylation reaction of readily available cage carboranyllithium reagents with aryl halides has been developed for the first time. This method is applicable to a wide range of aryl halide substrates including aryl iodides, aryl bromides, and heteroaromatic halides.  相似文献   
85.
This study reports the synthesis, curing, and optoelectronic properties of a solution‐processable, thermally cross‐linkable electron‐ and hole‐blocking material containing fluorene‐core and three periphery N‐phenyl‐N‐(4‐vinylphenyl)benzeneamine ( FTV ). The FTV exhibited good thermal stability with Td above 478 °C in nitrogen atmosphere. The FTV is readily cross‐linked via terminal vinyl groups by heating at 160 °C for 30 min to obtain homogeneous film with excellent solvent resistance. Multilayer PLED device [ITO/PEDOT:PSS/cured‐ FTV /MEH‐PPV/Ca (50 nm)/Al (100 nm)] was successfully fabricated using solution processed. Inserting cured‐ FTV is between PEDOT:PSS and MEH‐PPV results in simultaneous reduction in hole injection from PEDOT:PSS to MEH‐PPV and blocking in electron transport from MEH‐PPV to anode. The maximum luminance and maximum current efficiency were enhanced from 1810 and 0.27 to 4640 cd/m2 and 1.08 cd/A, respectively, after inserting cured‐ FTV layer. Current results demonstrate that the thermally cross‐linkable FTV enhances not only device efficiency but also film homogeneity after thermal curing. FTV is a promising electron‐ and hole‐blocking material applicable for the fabrication of multilayer PLEDs based on PPV derivatives. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 000: 000–000, 2012  相似文献   
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The W/O xanthan fermentation is simulated by integrating the microbial kinetic behaviors and the multiple-phase process characteristics. Model 1 assumes uniform redistribution of cells, substrates and product by frequent droplet breakup and coalescence. Model 2 simulates the system of viscous aqueous phase with minimal droplet breakup and component redistribution. The real fermentation should proceed within the bounds set by the two models. Effects of various parameters are evaluated. The aqueous-phase xanthan concentration (Xn) and volumetric productivity (QP) achieved at 200 h are used as the indicators. Xn and QP increase with nitrogen-source concentration (SNO) initially but plateau (Model 1) or decrease slightly (Model 2) at high SNO. Xn (at 200 h) decreases with increasing aqueous-phase volume fraction (f). QP, however, increases with f reflecting its basing on the total dispersion volume. Increasing agitation and aeration result in higher Xn and QP. The higher agitation enhances the G/O interfacial oxygen transfer and reduces the droplet size. Increasing aeration improves the G/O interfacial transfer but increases the droplet size. Its net positive effect implies a rate-limiting step at G/O interface. The W/O fermentation can produce far higher Xn (> 200 kg/m3) and QP( > 0.8 kg/m3-h) than the conventional fermentation (Xn ~ 50 kg/m3, QP ~ 0.5 kg/m3-h).  相似文献   
87.
Zhao  Ying  Mei  Zheng  Zhao  Feng-Qi  Xu  Si-Yu  Ju  Xue-Hai 《Structural chemistry》2021,32(1):387-394
Structural Chemistry - The ReaxFF-lg is used to simulate the thermal decomposition of the pure nitroglycerin (NG) and nitroglycerin/nano-Al (NG/Al) systems. The simulation results show that the...  相似文献   
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Aqueous electrolytes are safe, economic, and environmentally friendly. However, they have a narrow potential window. On the other hand, organic electrolytes exhibit good thermodynamic stability but are inflammable and moisture sensitive. In this study, we prepared water–PEG–lipid ternary electrolytes(TEs). To combine the advantages of water, polyethylene glycol(PEG) and propylene carbonate(PC). The nonflammable mixed electrolytes exhibited a wide potential window of about 2.8 V due to the beneficial effects of PEG and PC. Using these TEs, a lithium manganate–active carbon ion capacitor could be operated at 2.4 V with an energy density of 32 Wh/kg, based on the total active electrode material(current density of 3.3 m A/cm~2). This value was significantly higher than that achieved using an aqueous electrolyte, thereby rationalizing the higher energy density.  相似文献   
90.
A highly sensitive liquid chromatography–tandem mass spectrometry method was developed and validated for the determination of limonin in beagle dog plasma using nimodipine as internal standard. The analyte and internal standard (IS) were extracted with ether followed by a rapid isocratic elution with 10 mm ammonium acetate buffer–methanol (26:74, v/v) on a C18 column (150 × 2.1 mm i.d.) and subsequent analysis by mass spectrometry in the multiple reaction monitoring mode. The precursor to product ion transitions of m/z 469.4 → 229.3 and m/z 417.2 → 122.0 were used to measure the analyte and the IS. The assay was linear over the concentration range of 0.625–100 ng/mL for limonin in dog plasma. The lower limit of quantification was 0.312 ng/mL and the extraction recovery was >90.4% for limonin. The inter‐ and intra‐day precision of the method at three concentrations was less than 9.9%. The method was successfully applied to pharmacokinetic study of limonin in dogs. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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