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A design for the fabrication of metallic nanoparticles is presented by thermal dewetting with a chemically heterogeneous nano-template. For the template, we fabricate a nanostructured polystyrene-b-polydimethylsiloxane (PS-b-PDMS) film on a Si|SiO2 substrate, followed by a thermal annealing and reactive ion etching (RIE) process. This gives a template composed of an ordered hexagonal array of SiOC hemispheres emerging in the polystyrene matrix. After the deposition of a FePt film on this template, we utilize the rapid thermal annealing (RTA) process, which provides in-plane stress, to achieve thermal dewetting and structural ordering of FePt simultaneously. Since the template is composed of different composition surfaces with periodically varied morphologies, it offers more tuning knobs to manipulate the nanostructures. We show that both the decrease in the area of the PS matrix and the increase in the strain energy relaxation transfer the dewetted pattern from the randomly distributed nanoparticles into a hexagonal periodic array of L10 FePt nanoparticles. Transmission electron microscopy with the in situ heating stage reveals the evolution of the dewetting process, and confirms that the positions of nanoparticles are aligned with those of the SiOC hemispheres. The nanoparticles formed by this template-dewetting show an average diameter and center-to-center distance of 19.30 ± 2.09 nm and 39.85 ± 4.80 nm, respectively. The hexagonal array of FePt nanoparticles reveals a large coercivity of 1.5 T, much larger than the nanoparticles fabricated by top-down approaches. This approach offers an efficient pathway toward self-assembled nanostructures in a wide range of material systems.

A design for the fabrication of metallic nanoparticles is presented by thermal dewetting with a chemically heterogeneous nano-template. For the template, we fabricate a nanostructured polystyrene-b-polydimethylsiloxane (PS-b-PDMS) film on a Si|SiO2 substrate, followed by a thermal annealing and reactive ion etching (RIE) process. This gives a template composed of an ordered hexagonal array of SiOC hemispheres emerging in the polystyrene matrix. After the deposition of a FePt film on this template, we utilize the rapid thermal annealing (RTA) process, which provides in-plane stress, to achieve thermal dewetting and structural ordering of FePt simultaneously. Since the template is composed of different composition surfaces with periodically varied morphologies, it offers more tuning knobs to manipulate the nanostructures. We show that both the decrease in the area of the PS matrix and the increase in the strain energy relaxation transfer the dewetted pattern from the randomly distributed nanoparticles into a hexagonal periodic array of L10 FePt nanoparticles. Transmission electron microscopy with the in situ heating stage reveals the evolution of the dewetting process, and confirms that the positions of nanoparticles are aligned with those of the SiOC hemispheres. The nanoparticles formed by this template-dewetting show an average diameter and center-to-center distance of 19.30 ± 2.09 nm and 39.85 ± 4.80 nm, respectively. The hexagonal array of FePt nanoparticles reveals a large coercivity of 1.5 T, much larger than the nanoparticles fabricated by top-down approaches. This approach offers an efficient pathway toward self-assembled nanostructures in a wide range of material systems.

Molecules based on benzimidazolone‐dioxazine are known as blue/violet pigments and have been commercialized for decades. However, unfavorable solubility limits the application of these structures as building blocks of conjugated polymers despite their low band gaps. Herein, a series of donor–acceptor conjugated polymers containing soluble benzimidazolone‐dioxazine structures as the acceptors and oligothiophene as donors are synthesized and investigated. With increasing numbers of thiophene rings, the steric hindrance diminishes and high molecular weight polymers can be achieved, leading to an improved performance in organic field effect transistor devices. The hole mobility of polymers with three to six thiophene units is in the order of 10−1 cm2 V−1 s −1. Among all the polymers, polymer P3 with three thiophene units between benzimidazolone‐dioxazine structures shows the best hole mobility of 0.4 cm2 V−1 s −1. Grazing‐incidence wide‐angle X‐ray scattering results reveal that the high mobility of organic field‐effect transistors (OFETs) can be accredited by matched donor–acceptor packing in the solid thin films. [ABSTRACT FROM AUTHOR]

Background. Angina is a hallmark symptom of cardiovascular disease, which has become an important public health issue in Taiwan. The purpose of this study was to examine the prevalence of angina and its risk factors in elderly Taiwanese. Methods. The study was based on a government-sponsored health examination performed in Tao-Yuan, North Taiwan, from April to June 2001. A total of 2060 participants aged 65 years and older were enrolled. Data were collected through a physician-conducted Rose questionnaire, a biochemical blood test, and a physical examination. Multivariate logistic regression was used to evaluate the relationship between angina and risk factors. Results. Prevalence of angina was 15.0% in this study, 15.1% in men, and 14.4% in women. Women had a significantly higher body mass index (BMI), total serum cholesterol, and triglyceride. Participants with hypertension had a 1.6-fold 95% confidence interval (CI): 1.2-2.0 increased risk of having angina, 1.4-fold (95% CI: 1.0-1.9) increased risk for men and 2.1-fold (95% CI: 1.3-3.5) for women. Diabetes mellitus was associated with a 1.8-fold (95% CI: 1.2-2.6) increase in the risk for men. Conventional cardiovascular risk factors such as BMI, cholesterol, triglyceride, and smoking were not significantly associated with angina. Conclusions. The findings of this study suggest the need to prioritize hypertension treatment for elderly Taiwanese in both genders, and to provide adequate diabetes mellitus treatment for men, as these conditions are associated with the development of angina, a clinical indicator of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the fabrication of GaN metal–insulator–semiconductor (MIS) ultraviolet (UV) sensors with an La2O3 insulating layer. With a 5V applied bias, the leakage current of the fabricated MIS sensors with La2O3 insulating layers may be low to 4.95×10−11 A. The dark current was substantially reduced, and the UV-to-visible contrast ratio was enhanced by inserting the La2O3 layer. Furthermore, the noise equivalent power was substantially reduced, and detectivity was enhanced by using La2O3 insulating layers. [Copyright &y& Elsevier]