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In the industry of manufactured and assembled devices, the miniaturization and integration of small components with feature sizes on the order of 10 mm or smaller leads to new demands for inspection measurement systems. There are requirements for higher levels of resolution, precision, and accuracy, ideally with technologies that measure internal features and avoid causing damage to the original device. Three-dimensional (3D) techniques such as X-ray computed tomography (CT) may be used to non-destructively inspect internal geometries, or features, that are difficult to reach (or impracticable to access) with tactile probes. Traditional CT systems are, however, limited in resolution and achievable measurement accuracy. One alternative would be to use higher resolution instruments such as 3D X-ray microscopes and expand their measurement capabilities to the field of high precision metrology. This paper demonstrates how to perform non-destructive inspection in small-scale volumes, using a field-of-view (FOV) of about 5 mm diameter, and achieve dimensional measurements that are highly repeatable and accurate (with deviations from calibrated data within the ±1 μm range). This capability is relevant for the electronic industry, e.g., for measurements of camera modules or injection molded connectors, and for manufacturing highly efficient components, e.g., fuel spraying injectors and additive manufactured components with small internal features.

The design and preparation of porous materials with controlled structures and functionalities is crucial to a variety of absorption- or separation-relevant applications, including CO2 capture. Here, novel functional polymeric materials with three-dimensionally ordered macroporous (3DOM) structures are prepared by using colloidal crystals as templates using relatively simple, rapid, and inexpensive approaches. These ordered structures are used for the reversible CO2 capture from ambient air by humidity swing. Typically, the colloidal crystal template is synthesized from polymer latex particles of poly(methyl methacrylate) (PMMA) or polystyrene (PS). To maintain the functionality of the material, it is important to prevent the porous structure collapsing, which can occur by the hydrolysis of the ester bonds in conventional crosslinkers under basic conditions. This hydrolysis can be prevented by using a water-soluble crosslinker containing two quaternary ammonium moieties, which can be used to prepare stable porous crosslinked polymers with the monomer (vinylbenzyl)trimethylammonium chloride (VBTMACl) and using a PMMA-based colloidal crystal template. The hydroxide-containing monomer and dicationic crosslinker are synthesized from their chloride precursors, avoiding the ion-exchange step which causes shrinkage of the pores. An analysis of different methods for infiltrating the monomer solution into the colloidal crystal template shows that infiltration using capillary forces leads to fewer defects than infiltration under a partial vacuum. In addition, functional macroporous films with micrometer thickness are prepared from a template of PS-based colloidal crystals in a thin film. In general, the colloidal crystal templated materials showed improved CO2 absorption/desorption rates and swing sizes compared to a commercially available material with similar functional groups. This work could easily be extended to create a new generation of ordered macroporous polymeric materials with tunable functionalities for other applications. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the biologic links between progressive cellular and structural alterations within knee joint components and the development of symptomatic chronic pain. The study also investigated the molecular basis of alterations in nociceptive pathways caused by osteoarthritis (OA)-induced pain. It utilized Sprague-Dawley rats as animal models of knee joint OA pain. Study authors found structural changes in peripheral knee joint components in relation to central compartment alterations.

Three‐dimensionally ordered macroporous (3DOM) functional polymeric materials are synthesized by K. Matyjaszewski and co‐workers on page 4720 using colloidal crystal templating. These porous 3DOM materials are successfully used for reversible CO2 capture by humidity swing. [ABSTRACT FROM AUTHOR]