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911.
Heterogeneous catalysis is an important area of research that generates data as intricate as the phenomenon itself. Complexity is inherently coupled to the function of the catalyst and advance in knowledge can only be achieved if this complexity is adequately captured and accounted for. This requires integration of experiment and theory, high data quality and quality control, close interdisciplinary collaboration, and sharing of data and metadata, which is facilitated by the application of joint data management strategies. This Viewpoint Article first discusses the potential of a digital transition in catalysis research. Then, a summary of the current status in terms of data infrastructure in heterogeneous catalysis is presented, defining the various types of (meta-) data, from catalyst synthesis to functional analysis. Finally, an already implemented working concept for local data acquisition and storage is introduced and the benefits and further development directions for catalysis data use and sharing are discussed.  相似文献   
912.
913.
We describe two different ways of encapsulating within the fibrils of thermoreversible polymer gels the filaments of a supermolecular polymer formed by self-assembly of a bicopper complex. Heterogeneous nucleation is brought about with gels made from isotactic poly(styrene) while compound formation occurs with gels made from poly(hexyl isocyanate). These ways depend upon the interaction between the wings of the supermolecular polymer and the side groups of the polymer. In all cases, the filaments retain their 1-D structure. Preliminary results from magnetic susceptibility measurements show a striking difference between the pure and the encapsulated supermolecular polymer.  相似文献   
914.
Modification, forming and analytical characterisation of cellulose and cellulose solutions represents one of the most important research topics of the Thuringian Institute for Textiles and Plastics Research (TITK). The presentation provides information on the current capabilities of the institute and on the analytical methods developed in these fields.  相似文献   
915.
In analogy to the periodic system that groups elements by their similarity in structure and chemical properties, the hazard of chemicals can be assessed in groups having similar structures and similar toxicological properties. Here we review case studies of chemical grouping strategies that supported the assessment of hazard, exposure, and risk to human health. By the EU-REACH and the US-TSCA New Chemicals Program, structural similarity is commonly used as the basis for grouping, but that criterion is not always adequate and sufficient. Based on the lessons learned, we derive ten principles for grouping, including: transparency of the purpose, criteria, and boundaries of the group; adequacy of methods used to justify the group; and inclusion or exclusion of substances in the group by toxicological properties. These principles apply to initial grouping to prioritize further actions as well as to definitive grouping to generate data for risk assessment. Both can expedite effective risk management.  相似文献   
916.
917.
A. Berg  U. Iben  A. Meister 《PAMM》2003,2(1):372-373
A method for the numerical simulation of cavitation phenomena based on the thermodynamic properties of liquid and steam is described. Thereby, a homogeneous cavitation model using a fully compressible discretization technique is considered. The ability of the scheme is proven by numerical experiments.  相似文献   
918.
Cycloaliphatic polyolefins with functional groups were prepared by the Pd(II)-catalyzed addition polymerization of norbornene derivatives. Homo- and copolymers containing repeating units based on bicyclo[2.2.1] hept-5-en-2-ylmethyl decanoate (endo/exo-ratio = 80/20), bicyclo[2.2.1]hept-5-ene-2-carboxylic acid methyl ester (exo/endo = 80/20), bicyclo[2.2.1]hept-5-ene-2-methanol (endo/exo = 80/20), and bicyclo[2.2.1]hept-5-ene-2-carboxylic acid (100% endo) were prepared in 49–99% yields with {(η3-allyl)Pd(BF4)} and {(η3-allyl)Pd(SbF6)} as catalysts. The catalyst containing the hexafluoroantimonate ion was slightly more active than the tetrafluoroborate based Pd-complex.  相似文献   
919.
Well‐defined nanogels have become quite attractive as safe and stable carriers for siRNA delivery. However, to avoid nanoparticle accumulation, they need to provide a stimuli‐responsive degradation mechanism that can be activated at the payload's site of action. In this work, the synthetic concept for generating well‐defined nanohydrogel particles is extended to incorporate disulfide cross‐linkers into a cationic nanonetwork for redox‐triggered release of oligonucleotide payload as well as nanoparticle degradation under reductive conditions of the cytoplasm. Therefore, a novel disulfide‐modified spermine cross‐linker is designed that both allows disassembly of the nanogel as well as removal of cationic charge from residual polymer fragments. The degradation process is monitored by scanning electron microscopy (SEM) and fluorescence correlation spectroscopy (FCS). Moreover, siRNA release is analyzed by agarose gel electrophoresis and a fluorescent RNA detection assay. The results exemplify the versatility of the applied nanogel manufacturing process, which allows alternative stimuli‐responsive core cross‐linkers to be integrated for triggered oligonucleotide release as well as effective biodegradation for reduced nanotoxicity.

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