Effects of Rapid Thermal Annealing on The Structural and Local Atomic Properties of Zno: Ge Nanocomposite Thin Films

We have investigated the structural and local atomic properties of Ge nanocrystals (Ge-ncs) embedded ZnO (ZnO: Ge) thin films. The films were deposited by sequential sputtering of ZnO and Ge thin film layers on z-cut quartz substrates followed by an ex-situ rapid thermal annealing (RTA) at 600 degrees C for 30, 60, and 90 s under forming gas atmosphere. Effects of RTA time on the evolution of Ge-ncs were investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), hard x-ray photoelectron spectroscopy (HAXPES), and extended x-ray absorption fine structure (EXAFS). XRD patterns have clearly shown that fcc diamond phase Ge-ncs of sizes ranging between 18 and 27 nm are formed upon RTA and no Ge-oxide peak has been detected. However, cross-section SEM images have clearly revealed that after RTA process, Ge layers form varying size nanoclusters composed of Ge-ncs regions. EXAFS performed at the Ge K-edge to probe the local atomic structure of the Ge-ncs has revealed that as prepared ZnO: Ge possesses Ge-oxide but subsequent RTA leads to crystalline Ge structure without the oxide layer. In order to study the occupied electronic structure, HAXPES has been utilized. The peak separation between the Zn 2p and Ge 3d shows no significant change due to RTA. This implies little change in the valence band offset due to RTA. (C) 2015 AIP Publishing LLC.Wo

Effect of single-liquid priming agents on adhesive bonding to aluminum oxide of a methacrylic resin.

The purpose of this study was to evaluate the effects of acidic primers on adhesive bonding to sintered aluminum oxide (alumina). Alumina disks were primed with one of the following materials: Acryl Bond, All Bond 2 Primer B, Alloy Primer, Estenia Opaque Primer, Eye Sight Opaque Primer, M.L. Primer, MR. Bond, and Super-Bond Liquid. Specimens were then bonded with an acrylic resin initiated with partially oxidized tri-n-butylborane (TBBO), and bond strengths were determined. Unprimed specimen was employed as the control. Average bond strength before thermocycling ranged from 20.5 to 41.9 MPa, whereas post-thermocycling bond strength ranged from 0.0 to 40.0 MPa. Of the eight primers, Estenia Opaque Primer and Alloy Primer showed better adhesive performance than the other materials. It could thus be concluded that either Estenia Opaque Primer or Alloy Primer--which contained an adhesive monomer, 10-methacryloyloxydecyl dihydrogen phosphate (MDP)--was recommended for bonding alumina with TBBO-initiated resin

Picturing asthma in Turkey: results from the Turkish adult asthma registry

Introduction: National data on asthma characteristics and the factors associated with uncontrolled asthma seem to be necessary for every country. For this purpose, we developed the Turkish Adult Asthma Registry for patients with asthma aiming to take a snapshot of our patients, thereby assigning the unmet needs and niche areas of intervention. Methods: Case entries were performed between March 2018 and March 2022. A web-based application was used to record data. Study outcomes were demographic features, disease characteristics, asthma control levels, and phenotypes. Results: The registry included 2053 patients from 36 study centers in Turkey. Female subjects dominated the group (n = 1535, 74.8%). The majority of the patients had allergic (n = 1158, 65.3%) and eosinophilic (n = 1174, 57.2%) asthma. Six hundred nineteen (32.2%) of the patients had obese asthma. Severe asthma existed in 670 (32.6%) patients. Majority of cases were on step 3–5 treatment (n: 1525; 88.1%). Uncontrolled asthma was associated with low educational level, severe asthma attacks in the last year, low FEV1, existence of chronic rhinosinusitis and living in particular regions. Conclusion: The picture of this registry showed a dominancy of middle-aged obese women with moderate-to-severe asthma. We also determined particular strategic targets such as low educational level, severe asthma attacks, low FEV1, and chronic rhinosinusitis to decrease uncontrolled asthma in our country. Moreover, some regional strategies may also be needed as uncontrolled asthma is higher in certain regions. We believe that these data will guide authorities to reestablish national asthma programs to improve asthma service delivery