We investigated the growth process of carbon nanowalls (CNWs) on a SiO2 substrate by microwave plasma-enhanced chemical vapor deposition (MPECVD). It is revealed that the CNWs are grown at the fine-textured structure on the SiO2 and the growth process does not require the catalyst. The CNW initially has a semicircular shape. The height, thickness, and mesh size increase with growth time. It is found that the height of CNWs as a function of time obeys the square root law. Extremely high growth rate, approximately 10 µm/h, is achieved, in contrast to previous studies.

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Margarine and fat spread contain typical water-in-oil emulsions, including semi-solid fats, as continuous oil phases. The application of palm oil, one of the most promising trans-fat alternatives, for semi-solid fats is increasing. However, granular crystals often occur in palm-oil-based solid fats and cause deterioration. In this study, we carried out differential scanning calorimetry (DSC), optical microscopy, and X-ray diffraction (XRD) experiments on granular crystals in margarine. A conventional laboratoryscale technique was applied to examine thermal properties of high-melting fat fractions in granular crystals. In addition, microstructures of the granular crystal were precisely observed with a synchrotron radiation small-angle XRD (SR-μ-SAXD) technique by using a microbeam having a cross section of 5×5 μm 2 . The following results were obtained. (1) DSC indicated that granular crystals are composed of high-melting fractions having a melting temperature of 23°C. (2) Conventional XRD of granular crystals indicated that β-fat crystals of a triple chain length structure (β-3) melted below the melting of β′-fat of a double chain length structure (β′-2). (3) SR-μ-SAXD indicated that the fat crystals in normal margarine were β′-2. However, the fat crystals of the double and triple chain length structures were simultaneously observed at the center region of a granular crystal, whereas only the fat crystals of β-3 were observed at the outer region of a granular crystal. We analyzed the microstructures and formation processes of granular crystals in relation to the fractional crystallization of the β form of 1,3-dipalmitoyl-2-oleoyl-sn-glycerol promoted by crystallization and transformation of tripalmitin and tristearin fractions.

We report high-resolution 1.3mm continuum and molecular line observations of the massive protostar G28.20-0.05 with ALMA. The continuum image reveals a ring-like structure with 2,000 au radius, similar to morphology seen in archival 1.3cm VLA observations. Based on its spectral index and associated H30α emission, this structure mainly traces ionized gas. However, there is evidence for ∼ 30 M of dusty gas near the main mm continuum peak on one side of the ring, as well as in adjacent regions within 3,000 au. A virial analysis on scales of ∼2,000 au from hot core line emission yields a dynamical mass of ∼ 80M . A strong velocity gradient in the H30α emission is evidence for a rotating, ionized disk wind, which drives a larger-scale molecular outflow. An infrared SED analysis indicates a current protostellar mass of m * ∼ 24 M forming from a core with initial mass M c ∼ 400 M in a clump with mass surface density of Σ cl ∼ 3 g cm −2 . Thus the SED and other properties of the system can be understood in the context of core accretion models. Structure-finding analysis on the largerscale continuum image indicates G28.20-0.05 is forming in a relatively isolated environment, with no other concentrated sources, i.e., protostellar cores, above ∼ 1 M found from ∼0.1 to 0.4 pc around the source. This implies that a massive star is able to form in relative isolation and the dearth of other protostellar companions within the ∼ 1 pc environs is a strong constraint on massive star formation theories that predict the presence of a surrounding protocluster.

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