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The electronic structures of bulk and (001) surfaces of λ-MnO2and LiMn2O4have been studied with density functional theory. In λ-MnO2, the Mn oxidation state is +4 both in the bulk and at the (001) surface. In LiMn2O4, however, Mn atoms exhibit mixed Mn3+/Mn4+oxidation states in the bulk, while only Mn3+at the (001) surface, due to lower coordination with O atoms. The technically undesired Mn3+ions form at LixMn2O4(001) even for very small Li concentrations. Upon covering the LiMn2O4(001) surface with Al2O3, the oxidation state of surface Mn atoms changes from +3 to +4, which explains the improved performance of coated LiMn2O4cathodes in Li-ion batteries.

Summary: �In order to further understand the land–atmosphere interactions and increase the predictability of climate models, it is very important to investigate the effects of land-surface heterogeneities. In this paper, we considered roughness-length and stomatal-resistance heterogeneities in the regional climate model RegCM2 (Giorgi et al., 1993) that employs BATS (Dickinson et al., 1993) as the land surface scheme. In representing the subgrid heterogeneities, a computationally efficient method, which is a combination of the mosaic approach and the analytical type of the statistical-dynamical approach, is applied. The method is also characterized by converting the probability distribution of fundamental variables to probability distributions of derived quantities. By using the 3-month observational data of 1991 Meiyu season over China, we conducted coupled-model experiments, and found that: (i) For the whole model domain, the consideration of the two heterogeneities, in which intrapatch variability plays a very important role, greatly affects the simulations for the surface flux, wind, temperature and precipitation fields. (ii) The temperature and heat fluxes are quite sensitive to the heterogeneities, which displays the following rule: for a sub-region, the mean sensible heat flux decreases, the mean latent heat flux increases, and the mean surface temperature decreases with the increase of the heterogeneities. Furthermore, the mean latent heat flux is more sensitive to the heterogeneities than the mean sensible heat flux. (iii) It seems that the influence of stomatal-resistance heterogeneity on the latent heat flux is greater than that of roughness-length heterogeneity. Therefore, it is necessary to appropriately represent subgrid land-surface heterogeneities so as to improve regional climate modeling.

Using a proprietary technology known as the X-ACTTMsystem—Active-metering, Cyclone-separator Technology, a novel multi-dose inhaler (AirmaxTM) was developed to provide accurate and consistent dosing and a high-fine particle fraction of the drug. Formoterol, present as a blend with lactose monohydrate was delivered from AirmaxTMto obtain a nominal formoterol dose of 6 or 12 μg. The devices were tested using a five-stage liquid impinger and a unit dose sampling apparatus, operated under conditions specified in European Pharmacopoeia (2000). Fine-particle dose (FPD) was defined as the dose of the aerosolized drug particles with an aerodynamic diameter <5 μm and fine particle fraction (FPF) was the ratio of FPD to the total recovered dose. Dose per actuation was found to be 97.0±11.5% label claim (LC) or 5.8±0.7 μg (n=140), and 100±9.4% LC or 12±1.1 μg (n=440), for the 6 and 12 μg strengths, respectively. The mass median aerodynamic diameter was 2.4±0.1 μm (n=14), the geometric standard deviation 2.1±0.1 (n=14), and FPF 44.4±2.4% (n=14) for both strengths. Thus, the combination of active metering and cyclone separator produces highly consistent doses of formoterol that have a large respirable fraction.

A novel multi-dose inhaler has been developed to closely approach the characteristics of an “ideal” inhaler. The new device, AirmaxTM, uses proprietary technologies known as the X-ACTTMsystem to provide accurate and consistent dosing and excellent lung deposition—even at low inspiratory flow rates—combined with ease of use by the patient. Dose delivery was close to label claim, with relative standard deviation of typically around 5% for through-life emitted mass and around 10% for dose per actuation. At a flow rate (60–70 l/min), which corresponds to 4 kPa pressure drop across the device, the mean fine particle (<5 μm) dose (FPD) from 100, 200 and 400 μg strength budesonide AirmaxTMwas around 46, 98 and 244 μg, respectively. The mean FPD from 100 μg strength salbutamol AirmaxTMwas approximately 50 μg at the same flow rate. At 30 l/min, the delivered dose from AirmaxTMis over 85% label claim with fine particle fraction of over 35%. Performance was unaffected by shaking or orientation, provided the device was not used completely upside down, and priming was not required. There was no change in dose content uniformity and aerodynamic particle-size distribution after the devices have been stored unwrapped at 30°C/60% RH up to 24 months. Airmax is robust, portable and intuitive to use.

The influence of the vinylphenol content of poly(styrene‐co‐4‐vinylphenol) (STVPh) on the surface morphology of a blend of polystyrene (PS) and poly(N‐vinyl‐2‐pyrrolidone) (PVP) was investigated by time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) chemical imaging. The images obtained through the use of the ToF‐SIMS positive total ions and selected negative ions clearly show that the characteristic size of the dispersed phase (PVP) decreased with the addition of the STVPh‐5 (5 mol.% vinylphenol) random copolymer. The spectra obtained retrospectively from the matrix and the dispersed phase indicated that the matrix phase was very similar to the pure PS and that the dispersed phase was very similar to the pure PVP. The addition of the STVPh‐9 random copolymer to the blend of PS and PVP resulted in a totally different morphology: both PVP and PS became semi‐continuous and the dispersed particles are much larger. The morphological changes were caused by the formation of a single phase between PVP and STVPh‐9 due to an increase in the density of the hydrogen bond formed between PVP and STVPh‐9. When the vinylphenol content was <2 mol.%, the particle size of the PVP‐rich phase stayed the same. The compatibilizing effect was much weakened as the concentration of STVPh‐5 decreased to 1 wt.%. Copyright © 2001 John Wiley & Sons, Ltd.

The influence of the vinylphenol content of poly(styrene-co-4-vinylphenol) (STVPh) on the surface morphology of a blend of polystyrene (PS) and poly(N-vinyl-2-pyrrolidone) (PVP) was investigated by time-of-flight secondary ion mass spectrometry (ToF-SIMS) chemical imaging. The images obtained through the use of the ToF-SIMS positive total ions and selected negative ions clearly show that the characteristic size of the dispersed phase (PVP) decreased with the addition of the STVPh-5 (5 mol.% vinylphenol) random copolymer. The spectra obtained retrospectively from the matrix and the dispersed phase indicated that the matrix phase was very similar to the pure PS and that the dispersed phase was very similar to the pure PVP. The addition of the STVPh-9 random copolymer to the blend of PS and PVP resulted in a totally different morphology: both PVP and PS became semi-continuous and the dispersed particles are much larger. The morphological changes were caused by the formation of a single phase between PVP and STVPh-9 due to an increase in the density of the hydrogen bond formed between PVP and STVPh-9. When the vinylphenol content was &lt;2 mol.%, the particle size of the PVP-rich phase stayed the same. The compatibilizing effect was much weakened as the concentration of STVPh-5 decreased to 1 wt.%. Copyright © 2001 John Wiley & Sons, Ltd.

The polymer (BA-C8) was prepared by condensation polymerization of bisphenol A and 1,8-dibromooctane. The bromine atoms that were attached to the ends of the polymer chains could be used to determine the distribution of the end groups on the surface of BA-C8 polymer films. The surface morphology was studied using atomic force microscopy (AFM) tapping mode phase imaging. Direct observation of the growth process of a spherulite indicates that the diameter of the spherulite increases with time. The spatial distribution of the end group, Br, was determined by time-of-flight secondary ion mass spectrometry (ToF−SIMS) chemical imaging. For the amorphous films, a homogeneous distribution of the end groups at the surface was found, while for the semicrystalline films the end groups rearranged and preferentially segregated at the surface of the boundaries and the eyes of the spherulites.