Sintered diamond compacts using metallic cobalt binders

Method is developed for sintering diamond powder which uses metallic cobalt as binder. Present samples show maximum microhardness of over 3000 kg/sq mm on Knoop scale. Material may be used as hard surface coating or may compete with cubic boron nitride as abrasive grain

Parametric and laboratory aging studies of direct CO2 air capture simulating ambient capture conditions and desorption of CO2 on supported alkaline adsorbents

Alkali and alkaline earth metal oxides dispersed on high surface area γ-alumina were studied for the selective adsorption of CO2 under simulated ambient direct air capture (DAC) and subsequent temperature programmed desorption. Thermogravimetric analysis showed Na2O/γ-Al2O3 had superior adsorption and desorption via temperature programed desorption (TPD) relative to other supported metal oxides. Parametric and laboratory aging studies were conducted under simulated direct air capture of 400 ppm CO2, reflecting seasonal and locational ambient temperature and humidity conditions. Initial studies were performed on granular carriers and subsequently on washcoated ceramic monoliths. Aging studies were conducted on sample compositions of 10% Na2O/γ-Al2O3 granules and 10% Na2O + PX-80 γ-Al2O3 washcoat, deposited on a cordierite automotive-catalytic converter type monolith designed for low pressure drop in high air flow rates. Both selective adsorption and desorption of CO2 showed high stability with no signs of deactivation after 400+ hours of cyclic testing under a wide variety of simulated ambient conditions

Functional connectivity changes differ in early and late-onset alzheimer's disease

International audienceAbstract At a similar stage, patients with early onset Alzheimer's disease (EOAD) have greater neocortical but less medial temporal lobe dysfunction and atrophy than the late‐onset form of the disease (LOAD). Whether the organization of neural networks also differs has never been investigated. This study aims at characterizing basal functional connectivity (FC) patterns of EOAD and LOAD in two groups of 14 patients matched for disease duration and severity, relative to age‐matched controls. All subjects underwent an extensive neuropsychological assessment. Magnetic resonance imaging was used to quantify atrophy and resting‐state FC focusing on : the default mode network (DMN), found impaired in earlier studies on AD, and the anterior temporal network (ATN) and dorso‐lateral prefrontal network (DLPFN), respectively involved in declarative memory and executive functions. Patterns of atrophy and cognitive impairment in EOAD and LOAD were in accordance with previous reports. FC within the DMN was similarly decreased in both EOAD and LOAD relative to controls. However, a double‐dissociated pattern of FC changes in ATN and DLPFN was found. EOAD exhibited decreased FC in the DLPFN and increased FC in the ATN relative to controls, while the reverse pattern was found in LOAD. In addition, ATN and DLPFN connectivity correlated respectively with memory and executive performances, suggesting that increased FC is here likely to reflect compensatory mechanisms. Thus, large‐scale neural network changes in EOAD and LOAD endorse both common features and differences, probably related to a distinct distribution of pathological changes. Hum Brain Mapp 35:2978–2994, 2014. © 2013 Wiley Periodicals, Inc