This work focused on the potential application of various hydrophobic molecular sieves for the sorption of four model chlorinated volatile organic compounds (CVOCs, i.e., chloroform, trichloroethylene, tetrachloroethylene, and carbon tetrachloride) from dilute liquid water streams.
Results obtained thus far have shown that silicalite-1 has a high affinity for these CVOCs, higher in fact than Centaur® activated carbon, used as a benchmark in this study. Loading results for trichloroethylene from both liquid and vapor phase indicated that the liquid phase did not penetrate the pores of silicalite-1, while the solution did penetrate the pores of Centaur® and a dealuminated NaY used for comparison.
Finally, three definitions from the literature for the “hydrophobicity” of molecular sieves were considered. An alternative definition for hydrophobicity is introduced here, which is easy to determine and is based on water retention. 相似文献
We propose Adaptive Backbone Protocol ABP, a lightweight protocol for distributed formation of a backbone over Heterogeneous Wireless Networks. ABP does not require any neighborhood information and consequently scales well with the number of nodes and network size. We present an analytical framework to study the performance of ABP. By making the nodes rotate the role of backbone nodes, we extend the life of the network. 相似文献
Native mass spectrometry was evaluated for the qualitative and semiquantitative analysis of composite mixtures of antibodies representing biopharmaceutical products coexpressed from single cells. We show that by using automated peak fitting of the ion signals in the native mass spectra, we can quantify the relative abundance of each of the antibodies present in mixtures, with an average accuracy of 3%, comparable to a cation exchange chromatography based approach performed in parallel. Moreover, using native mass spectrometry we were able to identify, separate, and quantify 9 antibodies present in a complex mixture of 10 antibodies, whereas this complexity could not be unraveled by cation exchange chromatography. Native mass spectrometry presents a valuable alternative to existing analytical methods for qualitative and semiquantitative profiling of biopharmaceutical products. It provides both the identity of each species in a mixture by mass determination and the relative abundance through comparison of relative ion signal intensities. Native mass spectrometry is a particularly effective tool for characterization of heterogeneous biopharmaceutical products such as bispecific antibodies and antibody mixtures. 相似文献
This article presents the results of a survey that shows that older users differ in their attitude and experience towards the Internet not only according to their age or to their previous knowledge with Internet services, but also according to what they are expecting from this media. The aim of this study was to collect information about barriers on usage and perception of an online ticketing service for a nationwide public railway company, in order to enhance the notion of “accessibility” toward a broader understanding including non-technical accessibility factors as semantic accessibility and/or procedural accessibility. The results of the survey with 1,208 participants and additionally focus groups, interviews and qualitative analysis of user feedback indicate that in order to improve and optimize the usage of the online system for older adults, it is necessary to develop a system which is not only universally accessible, but also satisfies the specific expectations of senior users. This article concentrates on designing accessible user experiences and presents several recommendations to the area and for WCAG 2.0 according to the results. 相似文献
The removal of inclusions from molten silicon is necessary to satisfy the purity requirements for solar grade silicon. This
paper summarizes two methods that are investigated: (i) settling of the inclusions followed by subsequent directional solidification
and (infiltration by ceramic foam filters. Settling of inclusions followed by directional solidification is of industrial
importance for production of low-cost solar grade silicon. Filtration is reported as the most efficient method for removal
of inclusions from the top-cut silicon scrap. 相似文献
Using free‐energy simulations, we have shown that RevErbα‐induced DNA deformation preferentially occurs by induced fit rather than by conformational selection, even though the DNA is only slightly distorted in the complex. Our study shows that information on the sequence of binding events is needed to establish whether conformational selection or induced fit is operative, and that the presence of multiple apo‐state structures might not be enough to distinguish between these binding models. 相似文献
A cationic microgel with quaternized amine groups was prepared and used as a soft template for layer-by-layer (LbL) assemblies. The presence of quaternized amine groups inside the microgels was necessary to prevent rearrangements and subsequent bridging between the coated microgels, which were observed for the precursor microgels containing protonated primary amino groups. Sequentially, negatively charged polyelectrolyte poly(sodium styrene sulfonate) (PSS) and positively charged polyelectrolyte poly(diallyldimethylammonium chloride) (PDADMAC) were added to a suspension of quaternized microgels. This leads to an odd-even effect with respect to particle size and surface charge of the formed microgel–polyelectrolyte complexes (MPECs). MPECs with an even number of layers exhibit positive surface charge due to PDADMAC as the outermost layer and are larger compared to complexes with an odd number of layers, which are negatively charged having PSS in the outermost layer. Taking into account previous results (Macromolecules,2009,42, 1229), these observations show that electrostatic interactions are the major force for the odd-even effect in polyelectrolyte multilayers on microgels: the cationic groups of PDADMAC compete with the cationic moieties of the microgel for binding with the sulfonate groups of PSS. Concomitantly, a fluctuating size of the MPECs is induced by an osmotic pressure modulation within the microgel. In contrast, surface tension effects invoked by a possible varying hydrophilicity of the different terminal layers are negligible. 相似文献